Ecological Drivers and Consequences of Bumble Bee Body Size Variation - J. L. Fitzgerald; Jane E. Ogilvie; Paul J. CaraDonna (Environmental Entomology, 2022)
Body size is arguably one of the most important traits influencing the physiology and ecology of animals. Shifts in animal body size have been observed in response to climate change, including in bumble bees (Bombus spp. [Hymenoptera: Apidae]). Bumble bee size shifts have occurred concurrently with the precipitous population declines of several species, which appear to be related, in part, to their size. Body size variation is central to the ecology of bumble bees, from their social organization to the pollination services they provide to plants. If bumble bee size is shifted or constrained, there may be consequences for the pollination services they provide and for our ability to predict their responses to global change. Yet, there are still many aspects of the breadth and role of bumble bee body size variation that require more study. To this end, we review the current evidence of the ecological drivers of size variation in bumble bees and the consequences of that variation on bumble bee fitness, foraging, and species interactions. In total we review: (1) the proximate determinants and physiological consequences of size variation in bumble bees; (2) the environmental drivers and ecological consequences of size variation; and (3) synthesize our understanding of size variation in predicting how bumble bees will re- spond to future changes in climate and land use. As global change intensifies, a better understanding of the factors influencing the size distributions of bumble bees, and the consequences of those distributions, will allow us to better predict future responses of these pollinators.

Confluence: The Colorado River Compact's Centennial - Jason Anthony Robison (Wyoming Law Review, 2022)
Many thanks to Remi Bullock for that introduction and, more broadly, to the Potter

“How Do We Do This at a Distance?!” A Descriptive Study of Remote Undergraduate Research Programs during COVID-19 - S. Farina; A. P. Summers; Rebecca A. Cole; J. C. Ayoob; J. Arnold; C. J. Murren; P. Ordonez; M. Minkara; C. Mathis; A. Osano; E. Padilla-Crespo; S. Palchoudhury; et al. (CBE Life Sciences Education, 2022)
The COVID-19 pandemic shut down undergraduate research programs across the United States. A group of 23 colleges, universities, and research institutes hosted remote under- graduate research programs in the life sciences during Summer 2020. Given the unprec- edented offering of remote programs, we carried out a study to describe and evaluate them. Using structured templates, we documented how programs were designed and im- plemented, including who participated. Through focus groups and surveys, we identified programmatic strengths and shortcomings as well as recommendations for improvements from students’ perspectives. Strengths included the quality of mentorship, opportuni- ties for learning and professional development, and a feeling of connection with a larg- er community. Weaknesses included limited cohort building, challenges with insufficient structure, and issues with technology. Although all programs had one or more activities related to diversity, equity, inclusion, and justice, these topics were largely absent from

Quantifying Subsurface Flow and Solute Transport in a Snowmelt-Recharged Hillslope With Multiyear Water Balance - Anh Phuong Tran; Amanda Henderson; Jiamin Wan; Tetsu Tokunaga; Wenming Dong; W. S. Brown; Alexander W. Newman; Curtis A. Beutler; Kenneth Hurst Williams (Water Resources Research, 2022)
AbstractQuantifying flow and transport from hillslopes is vital for understanding water quantity and quality in rivers, but remains obscure because of limited subsurface measurements. Using measured hydraulic conductivity K profiles and water balance over a single year to calibrate a transmissivity feedback model for a hillslope in the East River watershed (Colorado) proved unsatisfactory for predicting flow over the subsequent years. Well‐constrained field‐scale K were obtained by optimizing subsurface flux predictions over years having large differences in recharge, and by including estimates of interannual transfer of excess snowmelt recharge. Water and solute exports during high snowmelt recharge occur predominantly via shallow groundwater flow through weathered rock and soil because of their enlarged transmissivities under saturated conditions. Conversely, these shallow pathways are less active in snow drought years when the water table remains deeper within the weathering zone. Hillslope soil water monitoring showed that rainfall does not infiltrate deeply during summer and fall months, and revealed water losses consistent with model ET predictions. By combining water table‐dependent fluxes with pore water chemistry in different zones, time‐dependent rates of solute exports become predictable. As an example, calibrated K were combined with dissolved nitrogen concentrations in pore waters to show the snowmelt‐dependence of reactive nitrogen exported from the hillslope, further supporting the recent finding that the weathering zone is the dominant source of reactive nitrogen at this site. Subsurface export predictions can now be obtained for wide ranges of recharge based on measurements of water table elevation and profiles of pore water chemistry.

Community College Students in the Field: A review of a Community Conversation on Successful Programs and Strategies - A. N. Robin; K. O'Connell; A. A. Farmer; J. W. Lee; A. K. Varty; J. A. Hewlett (2022)
To explore how field experiences can be designed to engage more community college students, the Undergraduate Field Experience Research Network (UFERN) held a "community conversation" (Community Colleges in the Field: Successful Programs and Strategies) on 15 October 2021. The hour-long virtual meeting featured a panel of instructors who are involved in creating opportunities for community college students to learn in field environments. The goal was to offer insights and foster a conversation about successful strategies, unique challenges, and concrete practices for participants to use in their classes, programs, or institutions. Forty-one people from field stations and marine laboratories, community colleges, and various public universities from within the United States participated in the community conversation. Undergraduate field experiences (UFEs), where student learning occurs in nature, can take a variety of forms, from field laboratories embedded within on-campus courses, day-long or multi-day field trips, weeks-long residential field courses to paid research internships (O'Connell et al. 2021). Undergraduate field experiences of a variety of formats are associated with a litany of positive outcomes and are perceived as critical pathways to career and graduate opportunities in the field-based sciences (Petcovic et al. 2014, Fleischner et al. 2017, Klemow et al. 2019). For example, field courses for undergraduates are associated with higher major retention rates (in this case Ecology and Evolutionary Biology), and the narrowing of achievement gaps for underrepresented minority (URM) students (Beltran et al. 2020). In addition, students participating in field courses tend to graduate with higher GPAs and show gains in their sense of scientific self-efficacy (Beltran et al. 2020). Patrick (2010) found that field trip experiences strengthened students' understanding of process of science and positively influenced students' attitude toward biology. A field-based research experience was shown to also increase student self-efficacy and feeling of belonging in their discipline, in this case the geosciences (Kortz et al. 2020). However, UFEs are not equally accessible to all interested students and can be laden with unique barriers to entry, particularly for URM students and students from low socioeconomic backgrounds (Morales et al. 2020, Zavaleta et al. 2020, Flowers et al. 2021, O'Connell et al. 2021). For community college students, these challenges are magnified and accompanied by institutional-specific barriers (Hewlett, 2018). Community college students make up a large portion of the undergraduate student population in the United States. In the 2019–2020 academic year, an estimated 7.7 million students (around 35% of U.S. undergraduates) attended community colleges (US DOE 2020a). Almost half of all students graduating with a STEM degree in 2020 had attended community college at some point; however, degree completion and transfer rates for community college students remain low, especially in STEM fields (Zhang 2021). Students starting in community college switch out of STEM majors at higher rates than students who start at 4-year universities (NASEM 2016). Of students entering community college in a STEM program over a 7-year study period, 69% left, either by switching to non-STEM programs or leaving college altogether in comparison with 48% for 4-year college students (Chen 2013). Further, the probability of attaining a bachelor's degree in a STEM field was more than four times higher for students starting at a 4-year institution compared with students starting at 2-year institutions (Wang 2015). The student populations of 2-year institutions are typically far more diverse than their 4-year counterparts. United States community colleges serve higher percentages of URM students (US DOE 2020b), students over the age of 24 (US DOE 2020c), low-income students (US DOE 2016), students working more than 30 hours per week (US DOE 2016), first-generation college students (US DOE 2016), and students who are parents (Noll et al. 2017, Reed et al. 2021). Given the broad and well-established benefits for students who participate in field experiences, and an urgent need to increase the inclusion and retention of a diverse student population in the natural sciences, it is valuable to target interventions, such as field research programs and field-based courses, at the community college level. Amanda Robin is a PhD candidate at the University of California, Los Angeles (UCLA), and the director of the Community College Field Biology Alliance (CCFBA). The CCFBA is an all student-run organization established in 2018 that provides community college students with the opportunity to design and enact research projects with ecological and animal behavior components. Cohorts of interns from 15 community colleges in the greater Los Angeles area are assigned a graduate and an undergraduate student mentor. Over 9 months, the teams move through the entire scientific process from exploring the literature, developing a hypothesis, experimental design, data collection and analysis, and the presentation of a research poster. Additionally, interns attend monthly workshops aimed at providing practical skills. Community college students are recruited to apply for the program through advertisements at their home campuses. Over the past 4 years, the CCFBA has developed a contact list of community college deans, department chairs, faculty, academic counselors, and STEM program administrators. On a yearly basis, recruitment materials are sent via email to this list. In addition, the program has also developed more formalized working relationships with STEM programs at several 2-year institutions nearby to the UCLA campus. These institutions incorporate direct links to the program application on their undergraduate research websites and facilitate more extensive recruitment outreach. Occasionally, they facilitate information sessions and have provided supplemental funding to support their students' CCFBA programming. Each year the number of applications received has increased and the program currently averages about 60 per cycle, of which 10–15 students are accepted. The CCFBA does not have any course prerequisites or GPA requirements and prioritizes accepting interns to the program with no previous research experience. This is considered a program strength in that it provides access to research for a broad range of students. The CCFBA programming aims to provide a foundational experience upon which students can build, and purposefully seeks students who may not otherwise be ready for larger, more competitive research experiences. The CCFBA attempts to increase program accessibility through the extended nature of the program's timeline. By requiring small monthly time commitments over 9 months, interns can maintain outside commitments while engaging with research. The program emphasizes exposure to the scientific process over the resulting research product, allowing interns to scale back the scope of their projects when needed. This emphasis provides the flexibility necessary to tailor the experience to the needs of individuals. Alongside research experiences, the CCFBA also provides transfer-student-focused programming, including Q&A panels with graduate students who are former community college students and one-on-one support with application preparation. Further, each intern's undergraduate mentor is a transfer student. Graduate student mentors attend a workshop prior to starting the program that provides an overview of the transfer process. The CCFBA has found challenges in the areas of interpersonal support for interns, maintaining accessibility, ensuring mentor engagement, and sourcing funding. Holistically supporting interns and ensuring accessible programming is a key goal but poses challenges. Many interns have actively struggled with food and housing insecurities and/or faced personal or familial health crises while in the program. The program found it challenging as a student organization separate from where the community college students live and attend college to aid with personal crises. In response, the CCFBA has attempted to balance program rigor with the flexibility required to make the program realistically completable for the highest number of interns. Students do not receive course credit because of the logistical challenges of arranging this with each student's college, as each cohort comes from multiple individual institutions. Additionally, the quality and quantity of engagement from mentors has been difficult to standardize. More time spent communicating leadership expectations and the unique needs of community college students to mentors has mitigated some of these challenges. Finally, it has been a struggle to obtain funding that would support the expansion of the program in key ways, such as the provision of stipends for interns. Currently, a majority of program funding is secured through grants from student associations at UCLA. The average cost per intern for a remote program is ~200 dollars (USD), and the cost per intern during in-person programming is ~600 USD. All programming is provided at no cost to the community college students. Prior to the COVID-19 pandemic, program meetings were held in person and included a trip to a field station managed by the University of California Natural Reserve System ~2 hours outside of Los Angeles to collect data. Two cohorts have now been completed remotely with fieldwork conducted in the interns' neighborhoods. Technologies like Zoom and communication applications like Slack have helped to facilitate an engaged online community. This program model has proven to be flexible and could likely be successful in any location, even in areas with distinct seasons, as it designed to have data collection focused in the summer months. Furthermore, there is potential to use open-source ecological data sets or data collected by remote sensors if the prospective program needs to be conducted during times when weather may be unsuitable for outdoor field research or students are unable or unwilling to conduct research outside. While working remotely has presented challenges in maintaining student engagement, assisting interns with data collection, and providing the appropriate equipment for them to safely do so, there have been benefits. Remote programming has highlighted the synergy between ecological field research and online internships for community college students by enabling a higher number of interns to participate, securing guest speakers that otherwise would not have been able to speak in person, and making our program open to those unable to travel (regardless of pandemic restrictions). Further, conducting fieldwork within their own communities illuminates for interns that ecological fieldwork is not something only reserved for "far off" places. Alison Varty is a faculty member and chair of the Environmental Science major at College of the Siskiyous, a publicly funded community college in a rural California mountain town. Like most community college students, those at College of the Siskiyous struggle to fit traditional field experiences (summer field classes or extracurricular activities) into their schedules due to their responsibilities outside of school. To address this challenge, Professor Varty integrated field experiences into several credit-based classes offered during the academic year. Further, she instituted a requirement for students in the Environmental Science major to complete a discipline-related science research or work-related project prior to graduation. Most students fulfill this requirement through for-credit field experiences. Their work has included internships at the local research station (Castle Lake Research Station), the Shasta-Trinity or Klamath National Forest, local native plant nurseries, private forestry companies, and at the local fish hatchery. These kinds of field experiences are popular because they often lead to long-term employment. Professor Varty has reached an even broader audience by creating hybrid and fully online courses that include field experiences. Her hybrid field botany course engages students in the study of plants through online asynchronous activities, including autonomous asynchronous field trips. During these trips, students take weekly excursions on their own to collect plants to practice keying using commercially available field guides and to perform floral or fruit dissections. In addition, students attend four all day face-to-face, synchronous group field trips. These trips complement the asynchronous work by helping students learn to identify plants they encounter in the field and providing them with hands-on experience collecting overstory and understory plant community data using quadrat and point-centered quarter sampling, respectively, that they later analyze and summarize on their own. Varty also teaches a fully online environmental science class, which involves many field-based laboratory activities. She has observed that field laboratories can actually be more equitable than traditional "cookbook" laboratories, because all students can get outside to a school or park or lawn, whereas not every student may have the required supplies (e.g., measuring spoons) in their home. James Hewlett is a Professor of Biology at Finger Lakes Community College (FLCC) in Canandaigua, New York. In 2001, FLCC conducted an internal study to better understand the barriers to developing Undergraduate Research Experiences (UREs) and potential strategies for establishing an undergraduate research program. The study uncovered several interesting and unanticipated hurdles to establishing an undergraduate research program at a community college that were unrelated to the oft-cited financial barriers or ill-prepared students. For example, the weak connection between community colleges, external networks, and science researchers was found to be a serious barrier. The results were compiled and used to create a model for integrating research experiences into a community college. After an initial rollout at FLCC, these principles were tested at six partner institutions with support from the National Science Foundation. The result was the establishment of the Community College Undergraduate Research Initiative (CCURI) in 2007. Community College Undergraduate Research Initiative is currently a national network of 142 community colleges in 39 states and two countries focused on the development and implementation of undergraduate research programs. The CCURI model, which was originally constructed to address barriers at FLCC, has been modified and expanded for implementation throughout the CCURI network. In its current form, the CCURI model incorporates solutions to the known barriers to integrating research into the student experience at community colleges. The CCURI model involves three levels. The first, "Engage," aims to immerse students in research from the moment they enter the classroom as freshman and is designed to promote conceptual understanding while also exposing students to ongoing CCURI research projects. Student-centered activities are used to teach basic scientific concepts within the context of an ongoing research project. The second level of the program is called "Explore." After engaging students in research questions as part of the freshman courses, the CCURI model creates opportunities for students to explore those questions in greater depth. These opportunities allow the students to continue these projects as a part of embedded regular course offerings at the college (CUREs; Course Undergraduate Research Experiences), a degree program (PURE; Program Undergraduate Research Experience), or as part of a credit-bearing summer experience (SURE; Summer Undergraduate Research Experience). The third component of the CCURI model, "Connect," involves connecting community college faculty and students to larger research communities. The growing CCURI network has become a rich source of collaboration on both the curricular and research sides of the CCURI model. At this level, students are connected to research opportunities and prospects to transfer their experience to a four-year institution as they continue to pursue their STEM career. Community College Undergraduate Research Initiative has built a nationwide network of community colleges who are committed to offering undergraduate research experiences at their home institutions. Community College Undergraduate Research Initiative partner institutions can access a suite of course curricula and professional development opportunities focused on student research. Further, the CCURI team shares data from meta-analyses of CCURI institutions as a way to develop best practices that can be shared both inside and outside the network. The goal is to continue to broaden participation in undergraduate research at our nation's community colleges. Jimmy Lee is an associate professor at East Los Angeles College, a large community college located near downtown Los Angeles that serves a primarily Hispanic and Asian student population. During a summer when he was not teaching, Prof. Lee participated in the Research Experience for Teachers (RET) program at the Rocky Mountain Biological Laboratory (RMBL). The RET program embeds teachers from community colleges within research teams to strengthen the scientific expertise of teachers and create lasting partnerships between educators and NSF-funded researchers. Following his RET experience, RMBL hired Lee to serve as its Education Program Coordinator. This is part of a RMBL initiative to recruit URM students by engaging with faculty from community colleges. RMBL has spent many years networking with community college instructors like Prof. Lee to build a pipeline that attempts to prioritize the recruitment of URM students for their summer research program. These connections result in roughly 15% of the 40 students in the undergraduate research program being composed of community college students each year. Professor Lee has found that community college students are often unaware of the benefits associated with participating in large, funded research internship programs, such as those provided by the National Science Foundation's Research Experiences for Undergraduates (REU). He finds that sharing stories and testimonials is an effective strategy to engage community college students and expose them to the potential advantages of applying to these types of opportunities. In these conversations, he talks about his own experience as an RET program participant at RMBL. Lee's work highlights how RET and REU programs can work in tandem to achieve greater diversity in participation. In addition to sharing his own experiences, he also invites past REU students from RMBL to talk with prospective students about their research projects and overall experience. Seeing and hearing from peers who have successfully participated in these programs provides students with strategies that they can then incorporate into their own academic trajectories. Community conversation participants' questions focused on (1) the concrete challenges of funding—who receives funding, and from what sources, and (2) anticipating and responding to students' needs in the field or at field stations. Specific program funding sources: Field research and learning experiences are important teaching and developmental tools for retaining students in STEM fields. Providing these experiences for community college students presents some unique challenges. Presenters in the UFERN Community Conversation spotlighted examples of how their institution, organization, or classes addressed these challenges. A major challenge discussed was students' family, community, and job commitments, which make participation in long-duration traditional field and research programs difficult. College of Siskiyous responds to these obstacles by providing course credit for students' internships or field experiences that take place in the community where they live. The CCFBA attempts to address this issue by spreading the research and workshop commitment over 9 months, which keeps the time required for any one activity more manageable. The CCURI program offers students opportunities to engage with research in a variety of ways from classroom-based experiences, summer long trips, and full degree programs. Further, CCURI found that there was insufficient communication between community colleges and research institutions. They responded by creating a network for community college faculty and administrators interested in providing research experiences to their students and connecting them to larger academic research networks. Another challenge participants noted was that "research" as a concept can at times feel alien and intimidating to students, or that students may not think participating in research is possible for them. Prof. Lee encouraged community college faculty to discuss the benefits and accessibility of formal programs like REUs with their students, and provide information, encouragement, and support to students who might not otherwise consider these experiences. Where possible, faculty are encouraged to share their own or past students' first-hand accounts of research program participation to normalize the experience. Further, offering local opportunities for students to engage in research that is connected to the student's community or location can help increase accessibility of field-based learning and highlight the potential relevance of conducting fieldwork for students. Lastly, funding is a critical challenge for programming success. Community college students overall do not typically have the same financial resources as students at 4-year colleges. Any program that hopes to have community college student participants should take the financial needs of students into serious consideration when designing programming and establishing expected time commitments and when travel is required be prepared to offer funding at, or above, the level provided to students from 4-year colleges before the program begins. Looking toward the future, research institutions and field stations should consider creating authentic partnerships and connections with community college campuses. Community college faculty and administrators can award credit for field-based internship or work experiences, and/or they can connect with national networks like CCURI to introduce research experiences to their own campuses. Faculty are encouraged to experiment with course formats to include fieldwork in students' own neighborhoods, group field trips, and even overnight excursions. Research groups at 4-year institutions like the CCFBA, as well as field stations, can work to provide students with flexible and accessible longer, mentored research experiences. Programming that is specifically designed to be thoughtful about the unique barriers community college students face will benefit the field as whole by fostering the early careers of this currently underrepresented student population in our broader community of scholars. This paper was initiated based on a high degree of interest from the UFERN community in engaging community college students in field learning experiences. We thank all the participants in the 15 October 2021 Community Conversation and other conversations at UFERN network meetings for inspiring this paper. This work was supported by the National Science Foundation under RCN-UBE grant no. 1730756 to K. O'Connell, A.R. Berkowitz, G. Bowser, and J. Branchaw.

Sulfur Biogeochemical Cycling and Redox Dynamics in a Shale-Dominated Mountainous Watershed - Roelof Versteeg; H. Malenda-Lawrence; M. E. Conrad; H. R. Naughton; J. N. Christensen; Benjamin Gilbert; Marco Keiluweit; C. G. Anderson; Christian Dewey; Sergio Carrero; Kristin Boye; Patricia Fox; et al. (Journal of Geophysical Research: Biogeosciences, 2022)
AbstractSulfur (S) is an essential macronutrient and important component of the earth’s crust, and its cycling has critical impacts on trace metal mobility, water quality, and human health. Pyrite weathering is the primary pathway by which sulfur enters surface waters. However, biogeochemical cycling of sulfur in soils and the river corridor mediates sulfate exports. In this study, we identified the major forms of sulfur across multiple compartments and scales in a pristine mountainous watershed, including shale bedrock weathering profiles, hillslope soils, and alluvial floodplain sediments, in order to provide insight into biogeochemical sulfur cycling in a hydrologically variable alpine system. X‐ray absorption near‐edge spectroscopy (XANES) analysis of shale weathering profiles showed clear evidence of pyrite oxidation to sulfate, with large accumulations of intermediate S(0) (20%–53%). Micro‐scale XANES showed evidence of reprecipitation of pyrite at fracture surfaces within the permanently saturated zone. Organic sulfur dominated S speciation in shallow hillslope soil and floodplain sediment, with little evidence of reduced inorganic S. However, mackinawite formation, representing active sulfate reduction, was observed in saturated oxbow sediments and saturated weathered shale underlying floodplain sediments. Further evidence of sulfate reduction from aqueous sulfur isotopic analysis was observed in shallow groundwater transects across an Fe‐reducing meander, whereas increases in pore water sulfate concentrations implied sulfur oxidation at other locations. The data present an integrated picture of sulfur cycling in a shale‐dominated watershed, where riverine sulfate exports are mediated by biological cycling, particularly in redox‐stratified and temporally dynamic hyporheic zone sediments.

Estimating the heritability of female dispersal in yellow-bellied marmots (2022)

Effects of an introduced mustard, Thlaspi arvense, on soil fungal communities in subalpine meadows - A. N. Trautwig; S. D. Frey; M. A. Anthony; K. A. Stinson (Fungal Ecology, 2022)

Golden-Mantled Ground Squirrel ( Spermophilus lateralis ) and Yellow-Bellied Marmot ( Marmota flaviventris ) Intraspecific and Interspecific Perch Use and Interaction Dynamics in Gothic, Colorado - A. Dorr (2022)
Golden-mantled ground squirrels (Spermophilus lateralis) and yellow-bellied marmots (Marmota flaviventris) can both be found in abundance at high elevation meadows in the Rocky Mountains. Though different in behavior, both species inhabit and utilize the open meadows of Gothic in very similar ways. Both species utilize perches and respond to each other’s alarm calls. Additionally, here in the Gothic town site, both species’ have been studied and recorded for many years. This research project aims to examine how golden-mantled ground squirrels share habitat features and interact with yellow-bellied marmots in the Gothic town site. This was done by collecting observational data during the summer of 2022 in Gothic, Colorado. Using the

Climate change and phenology - David W. Inouye (WIREs Climate Change, 2022)
Climate change is a defining element of the current ecological landscape, with consequences ranging from global to local environments. One of the first indices of the ecological impact of the ongoing environmental changes was measurement of their effects on phenology, the seasonal timing of Crested Butte, Colorado, 81224, USA. Email: inouye@umd.edu recurring annual events such as the beginning of the growing season, timing of flowering, and breeding seasons of animals. Research has moved beyond Funding information simple descriptions of these temporal changes to investigations of their root National Science Foundation, Grant/ Award Numbers: DEB-0922080, DEB-1354104, DEB-1912006 causes, impacts, and consequences at both ecological and evolutionary time scales. This changing landscape, environmental, ecological, and evolution- ary, makes this an exciting, albeit sometimes depressing, time to be a scientist. Edited by Brendon M.H. Larson, Domain Editor, and Mike Hulme, Editor-in-Chief This article is categorized under: Assessing Impacts of Climate Change > Observed Impacts of Climate Change Climate, Ecology, and Conservation > Observed Ecological Changes

The shifting importance of abiotic and biotic factors across the life cycles of wild pollinators - Jane E. Ogilvie; Paul J. CaraDonna (Journal of Animal Ecology, 2022)
Abstract Organisms living in seasonal environments are exposed to different environmental conditions as they transition from one life stage to the next across their life cycle. How different life stages respond to these varying conditions is a fundamental aspect of biology and is critical for understanding how organisms will respond to environmental change. Despite the importance of animal pollinators, we lack a basic understanding of the influence of different environmental factors across their life cycles. We investigated the relative importance of climate conditions, food availability, and previous life stage abundance in a community of wild bumble bee species, asking: how do these three factors influence bee abundance at each life stage? We used a 7-year dataset to examine the importance of environmental conditions on the abundance of life stages in seven wild bumble bee species. We monitored climate conditions, the abundance of floral resources, and abundances of bees in each life stage across the active colony life cycle in a highly seasonal subalpine ecosystem in the Colorado Rocky Mountains, USA. Bee abundance at different life stages responded to environmental conditions in a consistent manner across the seven species. The survival and recruitment stage of the life cycle (assessed as abundance of overwintered queens) responded negatively to longer winters; the growth stage (assessed as abundance of workers) responded positively to floral resource availability; and the reproductive stage (assessed as abundance of males) was positively related to the abundance of the previous life stage (workers). Our long-term examination of annual bumble bees reveals a consistent set of responses in the abundance of each life stage to climate conditions, floral resource availability, and previous life stage abundance. Across species, these three factors each influenced a distinct life stage, illustrating how their relative importance can shift throughout the life cycle. The life-cycle approach we have taken with wild bumble bees highlights that important details about pollinator demography are overlooked without considering life stage-specific responses. Ultimately, it is these life-stage specific responses that shape population outcomes, not only for animal pollinators, but for many organisms living in seasonal environments.

Marmot mass gain rates relate to their group’s social structure - Sophia Todorov; Conner S. Philson; Daniel T. Blumstein (Behavioral Ecology, 2022)

Genetic and spatial variation in vegetative and floral traits across a hybrid zone - Maya Midzik; Geoffrey Broadhead; Mascha Bischoff; Robert A. Raguso; Diane R. Campbell (American Journal of Botany, 2022)
AbstractPremiseGenetic variation influences the potential for evolution to rescue populations from impacts of environmental change. Most studies of genetic variation in fitness‐related traits focus on either vegetative or floral traits, with few on floral scent. How vegetative and floral traits compare in potential for adaptive evolution is poorly understood.MethodsWe measured variation across source populations, planting sites, and genetic families for vegetative and floral traits in a hybrid zone. Seeds from families of Ipomopsis aggregata, I. tenuituba, and F1 and F2 hybrids of the two species were planted into three common gardens. Measured traits included specific leaf area (SLA), trichomes, water‐use efficiency (WUE), floral morphology, petal color, nectar, and floral volatiles.ResultsVegetative traits SLA and WUE varied greatly among planting sites, while showing weak or no genetic variation among source populations. Specific leaf area and trichomes responded plastically to snowmelt date, and SLA exhibited within‐population genetic variation. All aspects of floral morphology varied genetically among source populations, and corolla length, corolla width, and sepal width varied genetically within populations. Heritability was not detected for volatiles due to high environmental variation, although one terpene had high evolvability, and high emission of two terpenes, a class of compounds emitted more strongly from the calyx than the corolla, correlated genetically with sepal width. Environmental variation across sites was weak for floral morphology and stronger for volatiles and vegetative traits. The inheritance of three of four volatiles departed from additive.ConclusionsResults indicate stronger genetic potential for evolutionary responses to selection in floral morphology compared with scent and vegetative traits and suggest potentially adaptive plasticity in some vegetative traits.

Life-history traits predict responses of wild bees to climate variation - Z. M. Portman; J. W. Harrison; Pardee G.; Melanie R Kazenel; Sean R. Griffin; M. Stemkovski; Joshua S. Lynn; Rebecca E. Irwin; David W. Inouye (Proceedings of the Royal Society B: Biological Sciences, 2022)
Life-history traits, which are physical traits or behaviours that affect growth, survivorship and reproduction, could play an important role in how well organisms respond to environmental change. By looking for trait-based responses within groups, we can gain a mechanistic understanding of why environmental change might favour or penalize certain species over others. We monitored the abundance of at least 154 bee species for 8 consecutive years in a subalpine region of the Rocky Mountains to ask whether bees respond differently to changes in abiotic conditions based on their life-history traits. We found that comb-building cavity nesters and larger bodied bees declined in relative abundance with increasing temperatures, while smaller, soil-nesting bees increased. Further, bees with narrower diet breadths increased in relative abundance with decreased rainfall. Finally, reduced snowpack was associated with reduced relative abundance of bees that overwintered as prepupae whereas bees that overwintered as adults increased in relative abundance, suggesting that overwintering conditions might affect body size, lipid content and overwintering survival. Taken together, our results show how climate change may reshape bee pollinator communities, with bees with certain traits increasing in abundance and others declining, potentially leading to novel plant-pollinator interactions and changes in plant reproduction.

Disinfection byproducts formed during drinking water treatment reveal an export control point for dissolved organic matter in a subalpine headwater stream - Jonathon O. Sharp; Stephanie S. Lau; William A. Mitch; Vanessa A. Garayburu-Caruso; Laura T. Leonard; James C. Stegen; Gary F. Vanzin; Alexander W. Newman; Curtis A. Beutler; Kenneth Hurst Williams (Water research X, 2022)
Changes in climate, season, and vegetation can alter organic export from watersheds. While an accepted tradeoff to protect public health, disinfection processes during drinking water treatment can adversely react with organic compounds to form disinfection byproducts (DBPs). By extension, DBP monitoring can yield insights into hydrobiogeochemical dynamics within watersheds and their implications for water resource management. In this study, we analyzed temporal trends from a water treatment facility that sources water from Coal Creek in Crested Butte, Colorado. These trends revealed a long-term increase in haloacetic acid and trihalomethane formation over the period of 2005-2020. Disproportionate export of dissolved organic carbon and formation of DBPs that exceeded maximum contaminant levels were consistently recorded in association with late spring freshet. Synoptic sampling of the creek in 2020 and 2021 identified a biogeochemical hotspot for organic carbon export in the upper domain of the watershed that contained a prominent fulvic acid-like fluorescent signature. DBP formation potential analyses from this domain yielded similar ratios of regulated DBP classes to those formed at the drinking water facility. Spectrometric qualitative analyses of pre and post-reacted waters with hypochlorite indicated lignin-like and condensed hydrocarbon-like molecules were the major reactive chemical classes during chlorine-based disinfection. This study demonstrates how drinking water quality archives combined with synoptic sampling and targeted analyses can be used to identify and understand export control points for dissolved organic matter. This approach could be applied to identify and characterize analogous watersheds where seasonal or climate-associated organic matter export challenge water treatment disinfection and by extension inform watershed management and drinking water treatment.

Survival rates of translocated Gunnison sage‐grouse - Brad Weinmeister; James H. Gammonley; Scott Wait; Evan Phillips; Daniel J. Neubaum; Jonathan P. Runge; Nathan W. Seward (Wildlife Society Bulletin, 2022)
Abstract Translocations have been used as a management tool for the federally threatened Gunnison sage‐grouse ( Centrocercus minimus ) but have not been rigorously evaluated. We estimated survival of translocated Gunnison sage‐grouse during the first year following release. Survival rates differed among satellite population where grouse were released, and survival was lower during the first 75 days following release than during the remainder of the first year. Age and sex of translocated grouse also influenced survival, but the timing of translocation (spring or fall) was less influential. Survival estimates of translocated Gunnison sage‐grouse were comparable to available estimates for resident Gunnison and greater sage‐grouse ( C. urophasianus ), suggesting that translocations may be an effective management tool for maintaining isolated populations. However, annual male counts at leks in the release populations were variable and generally declining, indicating that past numbers of Gunnison sage‐grouse translocated to these populations may not be adequate to sustain local populations, if lek counts reflect true population trends. Given that translocation has been identified as a primary management action for the recovery of Gunnison sage‐grouse, we recommend that a long‐term strategy for a translocation program should be developed. The success of a Gunnison sage‐grouse translocation program should be carefully monitored and managers should consider prioritizing captures for translocations with subadult females and males.

The social microbiome: the relationship between the microbiome and sociality in a wild mammal - M. Pfau (2022)
The microbiome has a well-documented relationship with host behavior. Greater microbial diversity and specific microbes have been associated with improved fitness, though these associations have been studied almost exclusively in captive animals with implications for human health. In wild populations, the microbiome has important fitness consequences, such as being associated with mass gain and body condition, and specifically, microbial diversity has been associated with increased individual stability and resistance to over-domination of specific microbes. An individual's social behavior also has important fitness consequences for acquiring food resources and avoiding predation. While both factors individually influence fitness, the relationship between the microbiome and sociality is understudied. Here we use social network analysis to quantify the relationship between microbial diversity and a variety of attributes of social relationships in a wild, free-living population of yellow-bellied marmots (Marmota flaviventer). We found no significant associations between microbial diversity and social network measures, suggesting that in facultatively social mammals, microbial diversity does not explain variation in the social relationship structure. Further research must be completed to examine the impact of social behavior on microbial composition and diversity.

Habitat Quality Affecting the Body Mass of Golden-mantled Ground Squirrels - B. Spinner (2022)
In conservation, it is vital to understand how organisms use their habitat and what constitutes high quality habitat. This has become increasingly urgent in ecosystems impacted by direct or indirect human disturbances such as habitat loss or climate change. High elevation ecosystems are particularly vulnerable to climate change, putting pressure on the organisms in these systems. However, local and micro-scale heterogeneity across the landscape potentially offers a buffer against climate change by creating small-scale differences in habitat quaility. Small hibernating Commented [BS1]: Could insert a transition sentence mammals such as the golden-mantled ground squirrel (Callospermophilus lateralis) may leverage microclimates to cope the effects of a warming climate. This study used drone imagery to collect fine scale data on factors contributing to habitat quality within home ranges of golden- mantled ground squirrels in the vicinity of Rocky Mountain Biological Laboratory. Thermal variation, food resources, and the abundance of perches for individual home ranges were compared to body mass, which is a strong indicator of survival and fecundity. The goal of this study is to further our understanding of how local differences in the landscape enhance habitat quality for golden-mantled ground squirrels. No significant trends were found when the average temperature, abundance of food resources, or number of perches were compared to mean body mass. However, further analysis and the comparison to other methods of assessing habitat effects on fitness may provide insight the role of habitat quality in this system.

Combined Effects of Aridity and Herbivory on Plant Performance - L. Duncan (2022)

The Impact of Carrion Insects on Human Impacted Soil - B. Guijosa (2022)
Carrion plays an important role in maintaining ecosystems and providing resources for different forms of life, returning key nutrients to the environment and serving as a food source for animals. While vertebrates who consume carrion are well studied, invertebrates are not as well studied, primarily carrion insects. With the decline of mammalian scavengers due to human impact and removal of large vertebrate carcasses from ecosystems, there is a need to understand how effective insects are as scavengers, as they are common on carrion sources. In this experiment, different carrion insects were placed into containers containing poor soil, and after 3 weeks were removed and seeds were planted into the soil as a bioassay, where the root weight fraction was calculated and used to determine the quality of the soil. The results showed that carrion insects have varying influences on soil nutrients, with carrion beetles having more impact compared to flies and carrion alone.

Tritrophic mutualisms in a changing climate - A. M. Keeler (2022)
Warmer than average temperatures and decreased annual precipitation caused by climate change are affecting the growth and reproduction of many species, including flowering plants. Climatic shifts may affect angiosperm functional traits, such as water use efficiency and nectar sugar concentration, which can in turn alter the strength and incidence of interactions between plants and their mutualists. Climatic stress can separate mutualists, leading to additional alterations in partner traits which may have consequences for plant fitness. Here, we explore how warming temperatures, early snowmelt, and below-average annual precipitation (snow and summer monsoonal rains) can affect plant functional traits such as water use efficiency and lead to a loss of interaction with symbiotic rhizobia, thereby altering legume nitrogen content and leaf carbon and nitrogen isotopic signatures. In a snowmelt manipulative experiment, we found that early snowmelt increased nectar sugar concentrations, reduced plant total nitrogen, shifted the activity and phenology of plant-important rhizobia, and decreased legume water use efficiency relative to ambient snowmelt conditions. Decreased soil nitrogen inputs from senescing legume plants may alter competitive outcomes and growth rates of heterospecific plants in the local area. Additionally, an analysis of historical herbarium specimens revealed that warmer, drier conditions over time are associated with a loss of interactions between legumes and rhizobia and decreased plant water use efficiency. These two independent lines of evidence suggest that changing climate may destabilize mutualistic interactions and shift plant functional traits, ultimately affecting nitrogen inputs and plant community dynamics. 8

Forest Fuels and Management Considerations at the Willey Conservation Easement, Colorado - M. Philips (2022)

Nest Distribution of Bombus spp. Across Different Habitat Types - Wynn R. Walker (2022)
Despite bumble bees’ critical importance as pollinators throughout the montane regions of Colorado, little research has been done on their nesting habits. In order to conserve the populations of Bombus spp. in the West, better knowledge of their nest density and nesting habitats is needed. I hypothesized that (1) a nest searching technique would be successful, (2) Bombus spp. nests would be identified in three distinct habitats, and (3) there would be a difference in nest densities across habitats depending on the bumble bee species. The habitats that I searched were classified as wet meadow, dry meadow, and aspen forest. Across three separate sites, each habitat had a total of 9 plots. Each of these plots was 150 square meters. I spent 30 minutes at each site once a week searching for nests and Bombus activity. Results of this study showed success of the nest searching technique and identification of Bombus nests in all three habitat types, but there was insufficient data to form a conclusion regarding the nesting habitat preferences of different species. The conclusion of this study is that dry meadow has the highest nesting density and should be preserved. Because this habitat also functions as foraging habitat for Bombus species, the conservation of this land is beneficial for the whole life cycle of the pollinators

Revealing the direct and indirect effects of climate change on soil nutrient dynamics and forage resources in mountain ecosystems - Kenna E Rewcastle (2022)
The loss of aboveground plant diversity alters belowground ecosystem function; yet, the mechanisms underpinning this relationship and the degree to which plant community structure and climate mediate the effects of plant species loss remain unclear. Here, we explored how plant species loss through experimental removal shaped belowground function in ecosystems characterized by different climatic regimes and edaphic properties. We measured plant community composition as well as potential carbon (C) and nitrogen (N) mineralization and microbial extracellular enzyme activity in soils collected from four unique plant removal experiments located along an elevational gradient in Colorado, USA. We found that regardless of the identity of the removed species or the climate at each site plant removal decreased the absolute variation in potential N-mineralization rates and marginally reduced the magnitude of N- mineralization rates. While plant species removal also marginally reduced C- 12 mineralization rates, C-mineralization, unlike N-mineralization, displayed sensitivity to the climatic and edaphic differences among sites, where C-mineralization was greatest at the high elevation site that receives the most precipitation annually and contains the largest soil total C pools. Plant removal had little impact on soil enzyme activity. Removal effects were not contingent on the amount of biomass removed annually, and shifts in mineralization rates occurred despite only marginal shifts in plant community structure following plant species removal. Our results present a surprisingly simple and consistent pattern of belowground response to the loss of dominant plant species across an elevational gradient with different climatic and edaphic properties, suggesting a common response of belowground ecosystem function to plant species loss regardless of which plant species are lost or the broader climatic context.

Temporal variation in high elevation plant-pollinator communities - D. Bernal (2022)
Plant-pollinator communities contribute to global diversity and are a good indicator of the health of an ecosystem. Climate change is causing phenological changes of flowering plants and pollinators. Changes in plant phenology can lead to a pollinator not being able to find sufficient pollen and nectar resources, while plants may produce fewer seeds. The focus of this study is to compare species diversity of a plant-pollinator community across three years in Virginia Basin, CO. Species richness and species diversity were greater in 2021 and 2022 compared to 2000. These results support the idea that insects are moving to higher elevation due to climate change. Increasing our sampling effort could give us different results. Further study of plant-pollinator networks across a range of temporal scales is needed, as the ability for plants and pollinators to adapt to mismatch remains unclear.

Predicting the effects of climate change on the cross? scale epidemiological dynamics of a fungal plant pathogen - B. Gray; S. Coffey; M. Stahl; M. Brownell; Juliana Jiranek; C. Jessica Metcalf (Scientific Reports, 2022)

Effects of Environmental Pond Drying Cues on Asynarchus nigriculus Cannibalism Rates - M. Tainatongo (2022)
Mexican Cut Preserve in the Elk Mountains is home to a unique system of ponds with a high diversity of aquatic life. Many species of caddisflies inhabit the various temporary, semi- permanent, and permanent ponds, including Asynarchus nigriculus. A. nigriculus is an aggressive caddisfly species that occasionally engages in cannibalism. The factors that cause A. nigriculus to go from a detritivore diet to cannibalism are not fully known. However, there is evidence that pond drying events may prompt a shift to cannibalistic behaviors to provide A. nigriculus individuals with the nutrients necessary to develop quickly. My research tested whether some of the environmental factors associated with pond drying events induce cannibalism. Specifically, I evaluated increased presence of other caddisfly species, increased conductivity, and greater temperature fluctuations as potential cues for cannibalistic behavior. First, species density tests were used to determine how the presence of another species, Agrypnia deflata, affects cannibalism rates in A. nigriculus. Here, one treatment contained both A. nigriculus and A. deflata, while the other two treatments contained a population of only A. nigriculus and a population of A. deflata. Second, I used a 2x2 factorial design experiment to evaluate temperature and conductivity as cues for cannibalism. Thus, I used these two experiments to gather data on several abiotic and biotic environmental factors that could alter cannibalism rates in the species A. nigriculus.

Production of hydrogen peroxide in an intra-meander hyporheic zone at East River, Colorado - Amrita Bhattacharyya; T. D. Waite; T. Liu; X. Yuan; J. A. Davis; Patricia Fox; P. S. Nico; Dipankar Dwivedi; Kenneth Hurst Williams (Scientific Reports, 2022)
Abstract The traditionally held assumption that photo-dependent processes are the predominant source of H 2 O 2 in natural waters has been recently questioned by an increrasing body of evidence showing the ubiquitiousness of H 2 O 2 in dark water bodies and in groundwater. In this study, we conducted field measurement of H 2 O 2 in an intra-meander hyporheic zone and in surface water at East River, CO. On-site detection using a sensitive chemiluminescence method suggests H 2 O 2 concentrations in groundwater ranging from 6 nM (at the most reduced region) to ~ 80 nM (in a locally oxygen-rich area) along the intra-meander transect with a maxima of 186 nM detected in the surface water in an early afternoon, lagging the maximum solar irradiance by ∼ 1.5 h. Our results suggest that the dark profile of H 2 O 2 in the hyporheic zone is closely correlated to local redox gradients, indicating that interactions between various redox sensitive elements could play an essential role. Due to its transient nature, the widespread presence of H 2 O 2 in the hyporheic zone indicates the existence of a sustained balance between H 2 O 2 production and consumption, which potentially involves a relatively rapid succession of various biogeochemically important processes (such as organic matter turnover, metal cycling and contaminant mobilization). More importantly, this study confirmed the occurrence of reactive oxygen species at a subsurface redox transition zone and further support our understanding of redox boundaries on reactive oxygen species generation and as key locations of biogeochemical activity.

Simultaneous niche expansion and contraction in plant–pollinator networks under drought - J. Savage; B. L. Morrison; A. Schiffer; V. A. Reynolds; C. N. Morozumi (Oikos, 2022)
Global climate change threatens to substantially rearrange species interactions, yet we lack clear predictions on how these changes will cascade through communities. Many perturbations associated with climate change, such as droughts, will change resource levels, with consequences for species interactions and thus ecological network structure. Diet theory predicts foraging niche expansion when preferred resources are scarce, yet under severe resource reduction interspecific competition could alternatively increase niche partitioning. Such niche expansion and/or contraction could profoundly shape ecological network structure following perturbations, but whether these predictions hold at the community level is unclear. We studied the impacts of drought on plant–pollinator networks in long‐lived perennial plant communities in which drought affects flower and floral reward production. We assessed whether drought effects on available floral resources altered pollinator dietary niche breadth to drive higher network‐level generalization. Accounting for interaction abundance and species turnover, we compared plant–pollinator networks in two drought years and three non‐drought years. We found that drought restructured plant–pollinator networks, resulting in more generalization in terms of presence–absence of links, yet more specialization when accounting for quantitative network intensities. Our results support the application of diet theory to understanding how perturbations may impact ecological network structure.

Imputation of contiguous gaps and extremes of subhourly groundwater time series using random forests - Deb Agarwal; Boris Faybishenko; Charuleka Varadharajan; Utkarsh Mital; Carl I. Steefel; S. S. Hubbard; Baptiste Dafflon; Dipankar Dwivedi; Kenneth Hurst Williams (Journal of Machine Learning for Modeling and Computing, 2022)
Machine learning can provide sustainable solutions to gap-fill groundwater (GW) data needed to adequately constrain watershed models. However, imputing missing extremes is more challenging than other parts of a hydrograph. To impute missing subhourly data, including extremes, within GW time-series data collected at multiple wells in the East River watershed, located in southwestern Colorado, we consider a single-well imputation (SWI) and a multiple-well imputation (MWI) approach. SWI gap-fills missing GW entries in a well using the same well's time-series data; MWI gap-fills a specific well's missing GW entry using the time series of neighboring wells. SWI takes advantage of linear interpolation and random forest (RF) approaches, whereas MWI exploits only the RF approach. We also use an information entropy framework to develop insights into how missing data patterns impact imputation. We discovered that if gaps were at random intervals, SWI could accurately impute up to 90% of missing data over an approximately two-year period. Contiguous gaps constituted more complex scenarios for imputation and required the use of MWI. Information entropy suggested that if gaps were contiguous, up to 50% of missing GW data could be estimated accurately over an approximately two-year period. The RF-feature importance suggested that a time feature (months) and a space feature (neighboring wells) were the most important predictors in the SWI and MWI. We also noted that neither SWI nor MWI methods could capture the missing extremes of a hydrograph. To counter this, we developed a new sequential approach and demonstrated the imputation of missing extremes in a GW time series with high accuracy.

DEFINING THE ENDMEMBER SYSTEM OF US SOILS AND QUANTIFYING RELATIONSHIPS, AND A HYPERSPECTRAL APPROACH TO THE ALTERATION STRENGTH INDEX - Rachel Rulison (2022)
Soils form a complex part of the environment, providing important functions in systems such as food production, groundwater movement, and ecosystem health. There have been numerous studies on soil geochemistry and the origin of elements within soils, but few studies into quantifying the relationships between elements and geographical data on a national scale. Using geochemical data obtained by the USGS, the surficial soils of the US were defined by a 13-endmember system using Polytopic Vector Analysis and mapped in GIS. Correlation matrices provided Pearson’s correlation coefficients for elements in the Top 5 cm soil profile, the A horizon, and the C horizon. The Top 5 cm element concentrations were also correlated with the endmembers, and geographical data for land cover, soil order, and soil pH. The quantification of these relationships supported many of the spatial patterns shown in maps and provided insight into other relationships, especially where correlation is weaker. The high spectral resolution of hyperspectral imagery has provided revolutionary advancements in many fields, including mineral identification. Hyperspectral core data from the company Corescan allowed for quantifiable mineral proportions for core sections from Karaha Telaga-Bodas, in Indonesia, and Lake City Caldera, in Colorado. The Alteration Strength Index (ASI) is a value based on mineral parameters that correlate to rock strength. The incorporation of hyperspectral data in the ASI aimed to improve the accuracy of the mineralogical parameters and provide more reliable strength data which in turn would reduce the need for time-consuming lab testing. Results showed that for the Telaga Bodas and Lake City samples, the ASI was not able to provide rock strength estimates within a reasonable range, and calibration of mineralogical parameters may be needed for samples with low ASI values. Though hyperspectral data may be a valuable tool in this venture, other issues with the current ASI would need to be resolved.

Phenotypic plasticity and selection on leaf traits in response to snowmelt timing and summer precipitation - Ayaka Paul; Jocelyn Navarro; J. M. Powers; Diane R. Campbell (New Phytologist, 2022)
Summary Vegetative traits of plants can respond directly to changes in the environment, such as those occurring under climate change. That phenotypic plasticity could be adaptive, maladaptive, or neutral. We manipulated the timing of spring snowmelt and amount of summer precipitation in factorial combination and examined responses of specific leaf area (SLA), trichome density, leaf water content (LWC), photosynthetic rate, stomatal conductance and intrinsic water‐use efficiency (iWUE) in the subalpine herb Ipomopsis aggregata. The experiment was repeated in three years differing in natural timing of snowmelt. To examine natural selection, we used survival, relative growth rate, and flowering as fitness indices. A 50% reduction in summer precipitation reduced stomatal conductance and increased iWUE, and doubled precipitation increased LWC. Combining natural and experimental variation, earlier snowmelt reduced soil moisture, photosynthetic rate and stomatal conductance, and increased trichome density and iWUE. Precipitation reduction reversed the mortality selection favoring high stomatal conductance under normal and doubled precipitation, and higher LWC improved growth. Earlier snowmelt is a strong signal of climate change and can change expression of leaf morphology and gas exchange traits, just as reduced precipitation can. Stomatal conductance and SLA showed adaptive plasticity under some conditions.

Evolution and genomic basis of the plant penetrating ovipositor: a key morphological trait in herbivorous Drosophilidae - K. I. Verster; Noah K Whiteman; A. D. Gloss; J. N. Peláez; D. Haji; J. F. Ray; J. L. M. Charboneau; S. Chaturvedi (Proceedings of the Royal Society B, 2022)
Herbivorous insects are extraordinarily diverse, yet are found in only one-third of insect orders. This skew may result from barriers to plant colonization, coupled with phylogenetic constraint on plant-colonizing adaptations. The plant-penetrating ovipositor, however, is one trait that surmounts host plant physical defences and may be evolutionarily labile. Ovipositors densely lined with hard bristles have evolved repeatedly in herbivorous lineages, including within the Drosophilidae. However, the evolution and genetic basis of this innovation has not been well studied. Here, we focused on the evolution of this trait in Scaptomyza, a genus sister to Hawaiian Drosophila, that contains a herbivorous clade. Our phylogenetic approach revealed that ovipositor bristle number increased as herbivory evolved in the Scaptomyza lineage. Through a genome-wide association study, we then dissected the genomic architecture of variation in ovipositor bristle number within S. flava. Top-associated variants were enriched for transcriptional repressors, and the strongest associations included genes contributing to peripheral nervous system development. Individual genotyping supported the association at a variant upstream of Gαi, a neural development gene, contributing to a gain of 0.58 bristles/major allele. These results suggest that regulatory variation involving conserved developmental genes contributes to this key morphological trait involved in plant colonization.

Integrating natural gradients, experiments, and statistical modeling in a distributed network experiment: An example from the WaRM Network - T. W. Crowther; C. Rixen; M. Rodriguez-Cabal; Jeremiah A Henning; M. J. Hovenden; Kenna E Rewcastle; X. Jing; K. Grigulis; D. B. Metcalfe; S. Wipf; M. N. Barrios-Garcia; E. K. Cameron; et al. (Ecology and Evolution, 2022)
A growing body of work examines the direct and indirect effects of climate change on ecosystems, typically by using manipulative experiments at a single site or performing meta-analyses across many independent experiments. However, results from single-site studies tend to have limited generality. Although meta-analytic approaches can help overcome this by exploring trends across sites, the inherent limitations in combining disparate datasets from independent approaches remain a major challenge. In this paper, we present a globally distributed experimental network that can be used to disentangle the direct and indirect effects of climate change. We discuss how natural gradients, experimental approaches, and statistical techniques can be combined to best inform predictions about responses to climate change, and we present a globally distributed experiment that utilizes natural environmental gradients to better understand long-term community and ecosystem responses to environmental change. The warming and (species) removal in mountains (WaRM) network employs experimental warming and plant species removals at high- and low-elevation sites in a factorial design to examine the combined and relative effects of climatic warming and the loss of dominant species on community structure and ecosystem function, both above- and belowground. The experimental design of the network allows for increasingly common statistical approaches to further elucidate the direct and indirect effects of warming. We argue that combining ecological observations and experiments along gradients is a powerful approach to make stronger predictions of how ecosystems will function in a warming world as species are lost, or gained, in local communities.

Sex-specific reproductive strategies in wild yellow-bellied marmots ( Marmota flaviventer ): senescence and genetic variance in annual reproductive success differ between the sexes - M. B. Petelle; M. N. Dumas; S. St. Lawrence; Julien G. A. Martin; Daniel T. Blumstein (Behavioral Ecology and Sociobiology, 2022)
Owing to sex-specific reproductive strategies, the mean and variance in annual offspring production may differ between the sexes. In addition, there may be sex-specific changes in reproductive performance with age (e.g. senescence). We used 20 and 50 years of longitudinal data on male and female yellow-bellied marmots, respectively, to investigate sex-specific age effects and genetic variance in annual reproductive success. In both sexes, annual offspring production increased linearly with age until a peak was reached at 7 years. This was followed by a decline in annual offspring production in both sexes, indicative of reproductive senescence. However, the initial increase and the subsequent decline (senescence) in reproductive success were both faster in males compared to females. Genetic variance in annual offspring production was higher in males than in females, but heritability was low for both sexes. Additionally, we found no cross-sex genetic correlation in the number of offspring produced, possibly reflecting sex-specific selection related to the inter-sexual differences in reproductive strate- gies. There was an effect of year on annual offspring production in both sexes, with a high yearly correlation between the sexes emphasizing the importance of environmental variation in determining fitness. Overall, these results demonstrate the impact of sex-specific reproductive strategies on annual offspring production and suggest that male and female marmots may be evolving to separate phenotypic optima. This study further demonstrates the value and limitations of long-term studies investigating sex-based patterns of ageing in the wild. Significance This study on yellow-bellied marmots demonstrates the key constraints surrounding the research of age-related changes in reproduction in wild populations, which is especially challenging in males. Among these challenges are high immigration rates which prevent the estimation of exact age and maternal identity. Genetic analysis—the only reliable way to estimate paternity—has only been a recent development, limiting the number of father-son relationships available for analysis. The dataset used in this study is long term (20 years of data on males and 50 on females), partially overcoming these obstacles. Results show that reproductive success declines with age in both sexes, with a faster rate of decline in males compared to females, and is influenced by the environment. Genetically, male and female reproductive success is not correlated, revealing that both sexes may be following separate evolutionary trajectories.

Novel host unmasks heritable variation in plant preference within an insect population - Rebecca S Epanchin-Niell; Rachel A Steward; Carol L. Boggs (Evolution, 2022)
Introductions of novel plant species can disturb the historical resource environment of herbivorous insects, resulting in strong selection to either adopt or exclude the novel host. However, an adaptive response depends on heritable genetic variation for preference or performance within the targeted herbivore population, and it is unclear how heritability of host-use preference may differ between novel and historical hosts. Pieris macdunnoughii butterflies in the Rocky Mountains lay eggs on the nonnative mustard Thlaspi arvense, which is lethal to their offspring. Heritability analyses revealed considerable sex-linked additive genetic variation in host preference within a population of this butterfly. This was contrary to general predictions about the genetic basis of preference variation, which are hypothesized to be sex linked between populations but autosomal within populations. Evidence of sex linkage disappeared when butterflies were tested on methanol-based chemical extracts, suggesting these chemicals in isolation may not be the primary driver of female choice among available host plants. Although unexpected, evidence for within-population sex-linked genetic variation in preference for T. arvense over native hosts indicates that persistent maladaptive oviposition on this lethal plant must be maintained by alternative evolutionary dynamics such as migration- or drift-selection balance or pleiotropic constraints.

A Meteorology and Snow Data Set From Adjacent Forested and Meadow Sites at Crested Butte, CO, USA - Hannah M. Bonner; Eric Smyth; Eric E. Small; Mark S. Raleigh (Water Resources Research, 2022)
AbstractWe present meteorology and snow observation data collected at sites in the southwestern Colorado Rocky Mountains (USA) over three consecutive water years with different amounts of snow water equivalent (SWE) accumulation: A year with above average SWE (2019), a year with average SWE (2020), and a year with below average SWE (2021). This data set is distinguished by its emphasis on paired open‐forest sites in a continental snow climate. Approximately once a month during February–May, we collected data from 15 to 20 snow pits and took 8 to 19 snow depth transects. Our sampling sites were in open and adjacent forested areas at 3,100 m and in a lower elevation aspen (3,035 m) and higher elevation conifer stand (3,395 m). In total, we recorded 270 individual snow pit density and temperature profiles and over 4,000 snow depth measurements. These data are complimented by continuous meteorological measurements from two weather stations: One in the open and one in the adjacent forest. Meteorology data—including incoming shortwave and longwave radiation, outgoing shortwave radiation, relative humidity, wind speed, snow depth, and air and infrared surface temperature—were quality controlled and the forcing data were gap‐filled. These data are available to download from Bonner, Smyth, et al. (2022) at https://doi.org/10.5281/zenodo.6618553, at three levels of processing, including a level with downscaled, adjusted precipitation based on data assimilation using observed snow depth and a process‐based snow model. We demonstrate the utility of these data with a modeling experiment that explores open‐forest differences and identifies opportunities for improvements in model representation.

Species-specific traits predict whole-assemblage detritus processing by pond invertebrates - C. Leitz; Washko S. E.; O. J. Wilmot; A. Stogsdill; D. M. Krejsa; L. M. Demi; B. Cleveland; M. E. Perchik; M. Vlah; B. W. Taylor; I. D. Shepard; J. A. Balik; et al. (Oecologia, 2022)
Functional trait diversity determines if ecosystem processes are sensitive to shifts in species abundances or composition. For example, trait variation suggests detritivores process detritus at different rates and make different contributions to whole- assemblage processing, which could be sensitive to compositional shifts. Here, we used a series of microcosm experiments to quantify species-specific coarse and fine particulate organic matter (CPOM and FPOM) processing for ten larval cad- disfly species and three non-caddisfly species in high-elevation wetlands. We then compared trait-based models including life history, dietary, and extrinsic traits to determine which traits explained interspecific variation in detritus processing. Finally, we compared processing by mixed caddisfly assemblages in microcosms and natural ponds to additive predictions based on species-specific processing to determine if single-species effects are additive in multi-species assemblages. We found considerable interspecific variation in biomass-specific CPOM (13-fold differences) and FPOM (8-fold differences) processing. Furthermore, on a mass-specific basis, amphipods, chironomids, and caddisflies processed similar amounts of detritus, suggesting non-shredder taxa could process more than previously recognized. Trait models including dietary percent detritus, development rate, body size, and wetland hydroperiod explained 81 and 57% of interspecific variation in CPOM and FPOM processing, respectively. Finally, species-specific additive predictions were strikingly similar to mixed- assemblage processing in microcosms and natural ponds, with the largest difference being a 15% overestimate. Thus, additiv- ity of species-specific processing suggests single-species rates may be useful for understanding functional consequences of shifting assemblages, and a trait-based approach to predicting species-specific processing could support generating additive predictions of whole-assemblage processing.

Comparative impacts of long-term trends in snowmelt and species interactions on plant population dynamics - Nickolas M. Waser; Mary V. Price; Alison K. Brody; Rebecca E. Irwin; Diane R. Campbell (Journal of Ecology, 2022)
Abstract Climate change can impact plant fitness and population persistence directly through changing abiotic conditions and indirectly through its effects on species interactions. Pollination and seed predation are important biotic interactions that can impact plant fitness, but their impact on population growth rates relative to the role of direct climatic effects is unknown. We combined 13 years of experiments on pollen limitation of seed set and pre‐dispersal seed predation in Ipomopsis aggregata , a subalpine wildflower, with a long‐term demographic study that has documented declining population growth with earlier spring snowmelt date. We determined how pollen limitation and seed predation changed with snowmelt date over 21 years and incorporated those effects into an integral projection model to assess relative impacts of biotic factors on population growth. Both pollen limitation and the difference in stigma pollen load between pollen‐supplemented and control plants declined over years. Neither pollen limitation nor seed predation changed detectably with snowmelt date, suggesting an absence of indirect effects of that specific abiotic factor on these indices of biotic interactions. The projected biotic impacts of pollen limitation and seed predation on population growth rate were small compared to factors associated with snowmelt date. Providing full pollination would delay the projected date when earlier snowmelt will cause populations to fall below replacement by only 14 years. Synthesis . Full pollination and elimination of seed predation would not compensate for the strong detrimental effects of early snowmelt on population growth rate, which in I. aggregata appears driven largely by abiotic environmental factors. The reduction over two decades in pollen limitation also suggests that natural selection on floral traits may weaken with continued climate change. These results highlight the value of studying both abiotic factors and biotic interactions to understand how climate change will influence plant populations.

Variability in observed stable water isotopes in snowpack across a mountainous watershed in Colorado - Jeffrey Deems; S. S. Hubbard; Reed M. Maxwell; Markus Bill; Alexander W. Newman; W. S. Brown; Matthias Sprenger; Curtis A. Beutler; Kenneth Hurst Williams (Hydrological Processes, 2022)
AbstractIsotopic information from 81 snowpits was collected over a 5‐year period in a large, Colorado watershed. Data spans gradients in elevation, aspect, vegetation, and seasonal climate. They are combined with overlapping campaigns for water isotopes in precipitation and snowmelt, and a land‐surface model for detailed estimates of snowfall and climate at sample locations. Snowfall isotopic inputs, describe the majority of δ18O snowpack variability. Aspect is a secondary control, with slightly more enriched conditions on east and north facing slopes. This is attributed to preservation of seasonally enriched snowfall and vapour loss in the early winter. Sublimation, expressed by decreases in snowpack d‐excess in comparison to snowfall contributions, increases at low elevation and when seasonal temperature and solar radiation are high. At peak snow accumulation, post‐depositional fractionation appears to occur in the top 25 ± 14% of the snowpack due to melt‐freeze redistribution of lighter isotopes deeper into the snowpack and vapour loss to the atmosphere during intermittent periods of low relative humidity and high windspeed. Relative depth of fractionation increases when winter daytime temperatures are high and winter precipitation is low. Once isothermal, snowpack isotopic homogenization and enrichment was observed with initial snowmelt isotopically depleted in comparison to snowpack and enriching over time. The rate of δ18O increase (d‐excess decrease) in snowmelt was 0.02‰ per day per 100‐m elevation loss. Isotopic data suggests elevation dictates snowpack and snowmelt evolution by controlling early snow persistence (or absence), isotopic lapse rates in precipitation and the ratio of energy to snow availability. Hydrologic tracer studies using stable water isotopes in basins of large topographic relief will require adjustment for these elevational controls to properly constrain stream water sourcing from snowmelt.

Trout Creek Lycopsid Fossil Forest, Chaffee County, Colorado - Mike Viney; George Mustoe (Rocks & Minerals, 2022)

Column-Test Data Analyses and Geochemical Modeling to Determine Uranium Reactive Transport Parameters at a Former Uranium Mill Site (Grand Junction, Colorado) - C. Doc Richardson; Aaron D. Tigar (Minerals, 2022)
The long-term release of uranium from residual sources at former uranium mill sites was often not considered in prior conceptual and numerical models, as contaminant removal focused on meeting radiological standards. To determine the reactive transport parameters, column tests were completed with various influent waters (deionized water, site groundwater, and local river water) on sediment from identified areas with elevated uranium on the solid phase in (1) vadose-zone (VZ) sediments, (2) saturated-zone sediments with higher organic carbon content, and (3) both vadose- and saturated-zone sediments with additional gypsum content. The gypsum was precipitated when low-pH, high-sulfate, tailings fluids or acidic waste disposal water were buffered by natural aquifer calcite dissolution. In general, the resulting uranium release was higher in the sediments with greater uranium concentrations. However, the addition of deionized water (DI) to the VZ sediments delayed the uranium release until higher-alkalinity groundwater was added. Higher-alkalinity river water continued to remove uranium from the VZ sediments for an extended number of pore volumes, with the uranium being above typical standards. Thus, river flooding is more efficient at removing uranium from VZ sediments than precipitation events (DI water in column tests). Organic carbon provides a stronger uranium sorption surface, which can be explained with geochemical modeling or a larger constant sorption coefficient (Kd). Without organic carbon, the typical sorption in sands and gravels is easily measurable, but sorption is stronger at lower, water-phase uranium concentrations. This effect can be simulated with geochemical modeling, but not with a constant Kd. Areas with gypsum create situations in which geochemical sorption is more difficult to simulate, which is likely due to the presence of uranium within mineral coatings. All the above mechanisms for uranium release must be considered when evaluating remedial strategies. Column testing provides initial input parameters that can be used in future reactive transport modeling to evaluate long-term uranium release rates and concentrations.

Variability of Snow and Rainfall Partitioning Into Evapotranspiration and Summer Runoff Across Nine Mountainous Catchments - Michelle Newcomer; Markus Bill; S. S. Hubbard; P. James Dennedy-Frank; Erica R. Siirila-Woodburn; Matthias Sprenger; Alexander W. Newman; W. S. Brown; Curtis A. Beutler; Kenneth Hurst Williams (Geophysical Research Letters,, 2022)
AbstractUnderstanding the partitioning of snow and rain contributing to either catchment streamflow or evapotranspiration (ET) is of critical relevance for water management in response to climate change. To investigate this partitioning, we use endmember splitting and mixing analyses based on stable isotope (18O) data from nine headwater catchments in the East River, Colorado. Our results show that one third of the snow partitions to ET and 13% of the snowmelt sustains summer streamflow. Only 8% of the rainfall contributes to the summer streamflow, because most of the rain (67%) partitions to ET. The spatial variability of precipitation partitioning is mainly driven by aspect and tree cover across the sub‐catchments. Catchments with higher tree cover have a higher share of snow becoming ET, resulting in less snow in summer streamflow. Summer streamflow did not contain more rain with higher rainfall sums, but more rain was taken up in ET.

Does an achromatic border alter color discrimination of male Speyeria mormonia butterflies during mate searching? - S. Maass (2022)
Larval food stress for the butterfly Speyeria mormonia causes less pigmentation in female butterflies. For this reason, males may approach females with higher pigmentation more often because it is a sign that they are healthier. Past studies have shown that this could be true, but they have not taken into account the markings on the butterflies’ wings. The achromatic black markings in contrast with the orange color stimulus of the wing could cause the male butterflies to perceive the color stimulus differently than they would without the markings. I added a black border to butterfly decoys made from three different colored Pantone papers, representing a super stimulus, high pigmentation, and low pigmentation, and observed approaches by males to see whether the achromatic border makes a difference in the way males perceive the color stimulus. I hypothesized that I would see a 1:1 ratio of approaches to butterfly decoy pairs with the border, and that the ratio for decoy pairs with the border would not differ from those without the border. Only the super stimulus and high pigment pair with borders did not deviate from a 1:1 ratio of approaches by males. Comparing results for decoy pairs with the border and without the border, only the high pigment and low pigment pairs differed, with more approaches to the low pigment decoy with the border than without the border. This suggests that while pigmentation does matter in the likelihood of approach by a male, so does the black border and markings. Females with low pigmentation will still be approached because of their achromatic markings causing the male butterflies to perceive the color stimulus differently.

Beaver dams overshadow climate extremes in controlling riparian hydrology and water quality (Nature Commnications, 2022)
Hydrologic extremes dominate chemical exports from riparian zones and dictate water quality in major river systems. Yet, changes in land use and ecosystem services alongside growing climate variability are altering hydrologic extremes and their coupled impacts on riverine water quality. In the western U.S., warming temperatures and intensified aridification are increasingly paired with the expanding range of the American beaver-and their dams, which transform hydrologic and biogeochemical cycles in riparian systems. Here, we show that beaver dams overshadow climatic hydrologic extremes in their effects on water residence time and oxygen and nitrogen fluxes in the riparian subsurface. In a mountainous watershed in Colorado, U.S.A., we find that the increase in riparian hydraulic gradients imposed by a beaver dam is 10.7-13.3 times greater than seasonal hydrologic extremes. The massive hydraulic gradient increases hyporheic nitrate removal by 44.2% relative to seasonal extremes alone. A drier, hotter climate in the western U.S. will further expand the range of beavers and magnify their impacts on watershed hydrology and biogeochemistry, illustrating that ecosystem feedbacks to climate change will alter water quality in river systems.

Dye Tracing and the Effects of Infrastructure in Hidden River Cave, Horse Cave, KY - Alexa Franks (2022)
Hidden River Cave is a stream cave system found in Horse Cave, KY with continuous water flow of its two branches, Wheet River and East River. The infrastructure of the city of Hose Cave, KY was originally designed to utilize natural sinkholes for drainage of all wastewaters. The city uses many of these, now modified, sinkholes for wastewater disposal and storm water drainage. Historically, Hidden River Cave has been severely impacted by unmonitored dumping of contamination. To better understand and identify specific flow paths from sinkholes and infrastructure into Hidden River Cave, this study documented various sinkholes and other infrastructure, such as storm drains, sewer systems, and other undocumented pipes, that could send water from the surface to Hidden River Cave. The study focused on using fluorescent dyes injected into four sites in order to document how the water carrying these dyes moved through the cave system. These dyes were identified using charcoal dye receptors placed at six locations within Hidden River Cave. Additionally, passage cross-sections of two major branches of the cave were measured, while depth and velocity measurements were taken to calculate the discharge of the river in these branches of the cave. Dye trace results identified two flow paths and hypothesized a small groundwater basin based on the detection of various dyes within the cave from multiple injection sites. Discharge results appear to agree with the flow path interpretation derived from the dye traces. The most significant findings of this research include: 1) identifying multiple flow paths from various injection points, 2) determining the relationship between discharge of the Wheet River and East River in Hidden River Cave, and 3) hypothesizing a flow route based on a lack of detection from a previously unidentified injection point. These findings improve the understanding of the relationship between surface water catchment in the city of Horse Cave and the flow into Hidden River Cave.

A distributed temperature profiling system for vertically and laterally dense acquisition of soil and snow temperature - J. W. Fitzpatrick; P. McClure; S. Pullman; S. Fiolleau; F. H. Akins; Jack Lamb; I. Shirley; R. Busey; C. Brunetti; John Peterson; Stijn Wielandt; S. S. Hubbard; et al. (The Cryosphere, 2022)
Abstract. Measuring soil and snow temperature with high vertical and lateral resolution is critical for advancing the predictive understanding of thermal and hydro-biogeochemical processes that govern the behavior of environmental systems. Vertically resolved soil temperature measurements enable the estimation of soil thermal regimes, frozen-/thawed-layer thickness, thermal parameters, and heat and/or water fluxes. Similarly, they can be used to capture the snow depth and the snowpack thermal parameters and fluxes. However, these measurements are challenging to acquire using conventional approaches due to their total cost, their limited vertical resolution, and their large installation footprint. This study presents the development and validation of a novel distributed temperature profiling (DTP) system that addresses these challenges. The system leverages digital temperature sensors to provide unprecedented, finely resolved depth profiles of temperature measurements with flexibility in system geometry and vertical resolution. The integrated miniaturized logger enables automated data acquisition, management, and wireless transfer. A novel calibration approach adapted to the DTP system confirms the factory-assured sensor accuracy of ±0.1 ∘C and enables improving it to ±0.015 ∘C. Numerical experiments indicate that, under normal environmental conditions, an additional error of 0.01 % in amplitude and 70 s time delay in amplitude for a diurnal period can be expected, owing to the DTP housing. We demonstrate the DTP systems capability at two field sites, one focused on understanding how snow dynamics influence mountainous water resources and the other focused on understanding how soil properties influence carbon cycling. Results indicate that the DTP system reliably captures the dynamics in snow depth and soil freezing and thawing depth, enabling advances in understanding the intensity and timing in surface processes and their impact on subsurface thermohydrological regimes. Overall, the DTP system fulfills the needs for data accuracy, minimal power consumption, and low total cost, enabling advances in the multiscale understanding of various cryospheric and hydro-biogeochemical processes.

Population Growth and Municipal Water Insecurity in Mesa County, Colorado - null null; William Wallace (John Heinrichs Scholarly & Creative Activities Day, 2022)
The purpose of this project was to utilize GIS software to develop a population and daily domestic water resource requirement analysis for Mesa County, Colorado by answering the question of what municipalities within the county have the highest potential of developing water insecurities between the years 2000 and 2019. The methods for developing the spatiotemporal population change of Mesa County, Colorado utilize attribute manipulation and statistical tools within ArcGIS Pro. The four municipalities, Clifton, Loma, Fruita , Grand Junction, and Orchard Mesa experienced the greatest population increase and daily water resource requirement increase marking these areas as the most likely to develop water insecurities in the future. While substantial population growth has taken place over the past twenty years through the county, most of the of growth occurred between 2000 and 2010, allowing for municipalities to adapt to the increase in population over the past decade. This project took a broad view of the county’s daily water use and found that the county has access to enough fresh water to support a growing population, and that other factors such as surface water quality and management are a more pressing line of study.

Limnephilus externus Case Grazing Effects on Predation - G. Bobo (2022)
Predator prey interactions are essential components of ecosystems, especially in lower trophic levels as they fuel many other organisms. Many prey organisms have developed tactics to decrease the rate of predation. For example, larval caddisflies build cases out of sedge and other detritus in their environment. These cases provide caddisflies with more protection from predators relative to other aquatic invertebrates. However, one species of caddisfly, Limnephilus externus, has been observed grazing on its case. The reason for this is unknown, but I hypothesized that it could make them more vulnerable to predation. Here, I tested how grazed and ungrazed cases influenced rates of salamander predation on L. externus. Based on the results of the experiment, case grazing does not have a significant effect on predation rates. These results narrow down the possible reasons that L. externus case grazes, but further research needs to be done to determine to why case grazing occurs.

New Upper Cretaceous Microvertebrate Assemblage from the Williams Fork Formation, northwestern Colorado, U.S.A., and its Paleoenvironmental Implications - Nickolas Brand; Israel Sanchez; Andrew B. Heckert; Jaelyn Eberle (Acta Palaeontologica Polonica, 2022)
We describe a microvertebrate assemblage from the J&M site, of the Upper Cretaceous (Campanian-Maastrichtian) Williams Fork Formation. Breakdown of fossil bearing matrix was achieved with the use of heated dimethyl sulfoxide. Nine of the recovered taxa are new to both the J&M site and the Williams Fork Formation. The sharks Lonchidion griffisi, Chiloscyllium sp., and Cantioscyllium markaguntensis are the first non-batoid elasmobranchs reported from the Williams Fork Formation and are all represented by teeth. The rays Cristomylus and Psuedomyledaphus are also newly reported from teeth. The most common identifiable fossils were teeth of indeterminate amiids, most likely belonging to Melvius. Osteichthyan fossils new to the Williams Fork Formation include teeth of Paralbula, an indeterminate pycnodontid tooth plate fragment, and an indeterminate lungfish tooth fragment. A tooth of the teiid Peneteius is also the first reported from within the Williams Fork Formation. Alligatoroid teeth are relatively common and are extremely similar to those of the contemporaneous durophage Brachychampsa but are generically indeterminate. Terrestrial taxa were recovered in much smaller numbers. Theropod dinosaur fossils included isolated tooth fragments belonging to an indeterminate dromaeosaurid and, possibly, to Richardoestesia. We recovered both multituberculate and metatherian fossils in the form of isolated teeth. Some of these taxa are known from marine and estuarine deposits and, given that so many of these marine associated taxa have been recovered together, it seems likely that the J&M site is recording marine or estuarine influence within at least part of its depositional history. The mammalian taxa suggest a Judithian-Lancian age for the site, while records of the squamate Peneteius and the ray Myledaphus, suggest that the J&M site may be temporally transitional between other late Campanian and late Maastrichtian-aged localities.

Removing flowers of a generalist plant changes pollinator visitation, composition, and interaction network structure - A. M. Gruver; R. G. Dickson; Justin A. Bain; Paul J. CaraDonna (Ecosphere, 2022)
Abstract Pollination is essential for ecosystem functioning, yet our understanding of the empirical consequences of species loss for plant–pollinator interactions remains limited. It is hypothesized that the loss of abundant and generalized (well‐connected) species from a pollination network will have a large effect on the remaining species and their interactions. However, to date, relatively few studies have experimentally removed species from their natural setting to address this hypothesis. We investigated the consequences of losing an abundant, generalist native species from a series of plant–pollinator networks by experimentally removing the flowers of Helianthella quinquenervis (Asteraceae) from half of a series of 10 paired plots (15 m diameter) within a subalpine ecosystem. We then asked how the localized loss of this species influenced patterns of pollinator visitation, floral visitor composition, and interaction network structure. The experimental removal of Helianthella flowers led to an overall decline in plot‐level pollinator visitation rates and shifts in pollinator composition. Species‐level responses to floral removal differed between the two other abundant, co‐flowering plants in our experiment: Potentilla pulcherrima received higher visitation rates, whereas Erigeron speciosus visitation rates did not change. Experimental floral removal altered the structural properties of the localized plant–pollinator networks such that they were more specialized, less nested, and less robust to further species loss. Such changes to interaction network structure were consistently driven more by species turnover than by interaction rewiring. Our findings suggest that the local loss of an abundant, well‐linked, generalist plant can bring about diverse responses within intact pollination networks, including potential competitive and facilitative effects for individual species, changes to network structure that may render them more sensitive to future change, but also numerous changes to interactions that may also suggest flexibility in response to species loss.

Abundance and Identification of Hymenopteran Parasitoids in Euphydryas gilletti - C. Rodriquez (2022)
Introduced species are thought to be free of natural enemies when they are brought into a new area. Euphydryas gilletti was introduced to RMBL to the south of its native range in the northern Rockies. I used this butterfly to examine whether it has fewer parasitoids in its new environment. To check, this study focuses on a butterfly species (Euphydryas gillettii) introduced experimentally in the vicinity of the RMBL and the potential ecological interactions it has with the other insects in its novel habitat. This butterfly has been studied since it was introduced in 1977 but not much is known about its interactions with parasitoids in the area. I conducted a survey at RMBL of the presence of lepidopteran parasitoids and the amount of parasitism on the butterfly egg masses. I surveyed and located parasitoids by sweep-netting and bagged egg masses to check if parasitoids used the eggs as hosts. There were no significant differences in parasitoids found across subsites or when comparing collections between plant or the ground and no parasitoids emerged from Euphydryas gillettii egg masses. In conclusion, my observations suggest that although parasitoids are present, the introduced species E. gillettii does not interact with any parasitoids in this location, supporting the idea that introduced species may escape their natural enemies.

Perils of life on the edge: Climatic threats to global diversity patterns of wetland macroinvertebrates - L. B. Epele; E. Demierre; L. Maltchik; E. E. Scheibler; E. A. Williams-Subiza; M. G. Grech; S. Gascón; A. Boissezon; C. Stenert; O. Loskutova; M. C. Mlambo; Michelle I. Jeffries; et al. (Science of the Total Environment, 2022)
Climate change is rapidly driving global biodiversity declines. How wetland macroinvertebrate assemblages are responding is unclear, a concern given their vital function in these ecosystems. Using a data set from 769 minimally impacted depressional wetlands across the globe (467 temporary and 302 permanent), we evaluated how temperature and precipitation (average, range, variability) affects the richness and beta diversity of 144 macroinvertebrate families. To test the effects of climatic predictors on macroinvertebrate diversity, we fitted generalized additive mixed-effects models (GAMM) for family richness, and generalized dissimilarity models (GDMs) for total beta diversity. We found non-linear relationships between family richness, beta diversity and climate. Maximum temperature was the main climatic driver of wetland macroinvertebrate richness and beta diversity, but precipitation seasonality was also important. Assemblage responses to climatic variables also depended on wetland water permanency. Permanent wetlands from warmer regions had higher family richness than temporary wetlands. Interestingly, wetlands in cooler and dry-warm regions had the lowest taxonomic richness, but both kinds of wetlands supported unique assemblages. Our study suggests that climate change will have multiple effects on wetlands and their macroinvertebrate diversity, mostly via increases in maximum temperature, but also through changes in patterns of precipitation. The most vulnerable wetlands to climate change are likely those located in warm-dry regions, where entire macroinvertebrate assemblages would be extirpated. Montane and high-latitude wetlands (i.e., cooler regions) are also vulnerable to climate change, but we do not expect entire extirpations at the family level.

(Socio-)ecological tools and insights for a changing climate - Zachary James Miller (2022)
In one way or another, climate change is impacting all social, economic, and ecological systems on the planet. Scientists worldwide warn of catastrophic and irreversible damage to social and ecological systems in absence of rapid, far-reaching, and unprecedented shifts in energy and land use. Yet, many social systems continue to operate business-as-usual, and decision-making across multiple levels of social organization continues to neglect the use of scientific evidence to minimize long-term risk. Contemporary biodiversity losses are occurring on scales that surpass the major extinction events in geological records, threatening the loss of critical ecosystem services, such as pollination, that underpin myriad facets of human societies as well as ecosystem resilience. In my dissertation, I call into question conventional lethal sampling approaches for bumble bees, an economically and ecologically important pollinator group, and simultaneously advance non-lethal techniques. Additionally, with aims to advance climate action in Missouri, I investigate how state-level decision-makers and land-use experts are thinking about climate resilience in the context of rural Missouri. More specifically, in chapter one, I explore how the use of lethal sampling, a traditional entomological sampling approach, has changed over time with evidence of numerous declining bumble bee populations. Global declines of bumble bees are welldocumented and have spurred widespread conservation efforts. However, lethal sampling continues to serve as a common entomological practice despite conservation concern. In collaboration with a research team from the Galen lab, I review 411 bumble bee-related publications from 1970-2019 alongside records from over 230,000 pinned bumble bee pinned specimens to discern whether lethal sampling has decreased with heightened conservation awareness and availability of novel non-lethal sampling methods. Our literature review shows that lethal sampling of bumble bees has instead kept pace with publication output. Interestingly, the highest rates of lethal sampling are found in papers demonstrating conservation awareness and persist despite low scholarly impact in comparison to papers based on non-lethal alternatives. Facing numerous pressures, vulnerable bumble bee populations may be less resilient to traditional sampling norms than broadly assumed. We highlight non-lethal sampling alternatives and underscore the need for proactive, empirically informed sampling guidelines that reflect the conservation needs of bumble bee pollinators. In chapter two, I review advances in acoustic monitoring technologies for bumble bees and discuss potential applications. Acoustics show promise for use in bumble bee investigations, as bumble bees create a range of distinguishable sounds while flying, sonicating (buzzing on flowers to eject pollen) and interacting within the colony, making them amenable for acoustical surveys. Acoustics offer an alternative sampling approach that is affordable, scalable, and non-destructive, with potential to augment conservation and agricultural practices. Application of AMT to investigate bumble bees is still nascent in development, and improvements are needed across all stages of the AMT process, from sensor technologies and data transfer to audio classification and user interfaces. I review the sound-producing activities of bumble bees, highlighting extant research and underscoring opportunities for further investigation. I conclude by reiterating the importance of cross-disciplinary collaboration between ecologists and computer scientists to monitor and manage species of conservation concern. In chapter three, I advance acoustic applications in bumble bee research using a combination of field work and literature surveys. Leveraging technological advancements that allow for remote monitoring and automated processing of information, such as acoustics, has been identified as a key next step for pollinator research. I test whether the acoustics of bumble bee flight buzzes can be used to track morphological traits and phenological phases of foragers throughout the season. I used flight cage experiments and a literature survey to extend data on the relationship between the fundamental frequency of flight buzzes and body size across castes and species. I then use these data to test whether acoustics can track caste size dimorphisms across species and variation in intraspecific worker size. Next, I acoustically monitored wild bumble bee colonies in subalpine and alpine ecosystems in Colorado, United States, where I corroborated acoustic data with in-person observations to distinguish phenological phases (queens only vs. queens and workers) of the colonies. I demonstrate that remotely monitoring bumble bee colonies with acoustics can provide large datasets with cues for different morphological and phenological features of the colony and discuss potential applications. In chapter four, I investigate climate resilience in rural Missouri. Rural areas of the United States -- approximately 97 percent of the total land area -- often lag urban areas in the implementation of climate adaptation practices. Understanding how perspectives vary within and among actors in the rural land use decision-making ecosystem can help to identify catalysts and constraints for climate change adaptation planning and action. I conducted semi-structured interviews with 23 experts -- policymakers, state/federal agency professionals, non-profit organization leadership, and researchers -- at the nexus of rural land use, agriculture, natural resources, and conservation in Missouri to elucidate conceptualizations of climate resilience. I aligned interview questions with NOAA's Steps to Resilience to investigate participants' perceptions of the major vulnerabilities of rural communities and landscapes, threats to rural vitality, and potential concrete steps for making rural Missouri more resilient in the face of climate change. I then discuss examples of climate resilience in Missouri and conclude with suggestions for potential next steps towards climate resilience in the state.

Hibernation slows epigenetic ageing in yellow-bellied marmots - Robert Wayne; M. Pellegrini; C. Farrell; S. Snir; S. M. Horvath; J. Zoller; G. M. Pinho; J. Zhang; Amin Haghani; Julien G. A. Martin; Daniel T. Blumstein (Nature Ecology & Evolution, 2022)
Abstract Species that hibernate live longer than would be expected based solely on their body size. Hibernation is characterized by long periods of metabolic suppression (torpor) interspersed by short periods of increased metabolism (arousal). The torpor-arousal cycles occur multiple times during hibernation, and it has been suggested that processes controlling the transition between torpor and arousal states cause aging suppression. Metabolic rate is also a known correlate of longevity, we thus proposed the ‘hibernation-aging hypothesis’ whereby aging is suspended during hibernation. We tested this hypothesis in a well-studied population of yellow-bellied marmots (Marmota flaviventer), which spend 7-8 months per year hibernating. We used two approaches to estimate epigenetic age: the epigenetic clock and the epigenetic pacemaker. Variation in epigenetic age of 149 samples collected throughout the life of 73 females was modeled using generalized additive mixed models (GAMM), where season (cyclic cubic spline) and chronological age (cubic spline) were fixed effects. As expected, the GAMM using epigenetic ages calculated from the epigenetic pacemaker was better able to detect nonlinear patterns in epigenetic age change over time. We observed a logarithmic curve of epigenetic age with time, where the epigenetic age increased at a higher rate until females reached sexual maturity (2-years old). With respect to circannual patterns, the epigenetic age increased during the summer and essentially stalled during the winter. Our enrichment analysis of age-related CpG sites revealed pathways related to development and cell differentiation, while the season-related CpGs enriched pathways related to central carbon metabolism, immune system, and circadian clock. Taken together, our results are consistent with the hibernation-aging hypothesis and may explain the enhanced longevity in hibernators.

Legume germination is delayed in dry soils and in sterile soils devoid of microbial mutualists: Species-specific implications for upward range expansions - A. M. Keeler; Nicole E. Rafferty (Ecology and Evolution, 2022)
Climate change is affecting species and their mutualists and can lead to the weakening or loss of important interspecific interactions. Through independent shifts in partner phenology and distribution, climatic stress can separate mutualists temporally or spatially, leading to alterations in partner functional traits and fitness. Here, we explored the effects of the loss of microbial mutualists on legume germination success and phenology. In particular, we assessed the effects of mutualism loss via soil sterilization, increased drought, and introduction to novel soils found beyond the current distributions of two focal legume species in subalpine environments. Through common garden experiments in controlled environments, we found evidence that soil sterilization (and consequent microbial absence) and dry soils caused species-specific phenological delays of 2-5 weeks in germination, likely as a result of interaction loss between legumes and specialized germination-promoting soil microbes, such as mutualistic rhizobia. Delays in germination caused by a mismatch between legumes and beneficial microbes could negatively affect legume fitness through increased plant-plant competition later in the season. Additionally, we found evidence of the presence of beneficial microbes beyond the current elevational range of one of our focal legumes, which may allow for expansion of the leading edge, although harsh abiotic factors in the alpine may hinder this. Alterations in the strength of soil microbe-legume mutualisms may lead to reduced fitness and altered demography for both soil microbes and legumes.

On the similarity of hillslope hydrologic function: a clustering approach based on groundwater changes - Fadji Maina; P. James Dennedy-Frank; Erica R. Siirila-Woodburn; Haruko M. Wainwright (Hydrology and Earth System Sciences, 2022)
Abstract. Hillslope similarity is an active topic in hydrology because of its importance in improving our understanding of hydrologic processes and enabling comparisons and paired studies. In this study, we propose a holistic bottom-up hillslope clustering based on a region's integrative hydrodynamic response quantified by the seasonal changes in groundwater levels ΔP. The main advantage of the ΔP clustering is its ability to capture recharge and discharge processes. We test the performance of the ΔP clustering by comparing it to seven other common hillslope clustering approaches. These include clustering approaches based on the aridity index, topographic wetness index, elevation, land cover, and machine-learning that jointly integrate multiple data. We assess the ability of these clustering approaches to identify and categorize hillslopes with similar static characteristics, hydroclimate, land surface processes, and subsurface dynamics in a mountainous watershed – the East River – located in the headwaters of the Upper Colorado River Basin. The ΔP clustering performs very well in identifying hillslopes with six out of the nine characteristics studied. The variability among clusters as quantified by the coefficient of variation (0.2) is less in the ΔP and the machine learning approaches than in the others (> 0.3 for TWI, elevation, and land cover). We further demonstrate the robustness of the ΔP clustering by testing its ability to predict hillslope responses to wet and dry hydrologic conditions, of which it performs well when based on average conditions.

Revisions to the Wanakah Formation in and around Ouray County, Colorado - Lawrence S. Jones; Cassandra R. Fenton (Mountain Geologist, 2022)
A well-defined type section and consistent nomenclature are fundamental requirements for successful correlation of stratigraphic units and subsequent accurate paleogeographic reconstructions. The exact location of the original type section of the Middle Jurassic Wanakah Formation of the eastern Colorado Plateau was found in Ouray County, Colorado. Two nearby reference sections are described that supplement the lithologic descriptions in the original type section. These reference sections and the original type section constitute a “principal reference section” for the Wanakah Formation. Informal names “upper shale beds”, “marl member”, and “beds at Sawpit” have been used to describe the uppermost member of the Wanakah. These terms are replaced with the formal name, “Crooked Tree Member of the Wanakah Formation”, in the reference sections to avoid confusion, foster consistent usage, and facilitate litho-stratigraphic correlation.

The Evolution and Ecology of Interactions Between Ants and Honeydew-Producing Hemipteran Insects - Annika S. Nelson; Kailen A. Mooney (The Annual Review of Ecology, Evolution, and Systematics, 2022)
The interactions between ants and certain sap-feeding insects in the order Hemiptera are classic examples of food-for-protection mutualisms. In these associations, herbivorous hemipterans use a highly specialized, straw-like mouthpart to consume sap directly from plant phloem and xylem and, as a result, excrete a sugar-rich waste product called honeydew. Ant foragers use specialized adaptations to collect and share honeydew with nestmates and, in exchange, protect hemipterans against predators. The two key innovations underlying this interaction—hemipteran sap feeding and ant harvesting of honeydew—have driven the evolutionary success and ecological dominance of ants. These interactions also carry unique costs and benefits for each partner and are highly context dependent. Understanding the factors mediating this mutualism is critical, as these interactions have broader ecological consequences for the natural and agricultural ecosystems in which they are embedded.

An equation of state unifies diversity, productivity, abundance and biomass - K. Umemura; E. A. Newman; M. Brush; John Harte (Communications Biology, 2022)
To advance understanding of biodiversity and ecosystem function, ecologists seek widely applicable relationships among species diversity and other ecosystem characteristics such as species productivity, biomass, and abundance. These metrics vary widely across ecosystems and no relationship among any combination of them that is valid across habitats, taxa, and spatial scales, has heretofore been found. Here we derive such a relationship, an equation of state, among species richness, energy flow, biomass, and abundance by combining results from the Maximum Entropy Theory of Ecology and the Metabolic Theory of Ecology. It accurately captures the relationship among these state variables in 42 data sets, including vegetation and arthropod communities, that span a wide variety of spatial scales and habitats. The success of our ecological equation of state opens opportunities for estimating difficult-to-measure state variables from measurements of others, adds support for two current theories in ecology, and is a step toward unification in ecology.

Carrying the moral burden of safe fieldwork - Benjamin Blonder (Bulletin of the Ecological Society of America, 2022)
Fieldwork in ecology and the environmental sciences often leads to negative physical and emotional outcomes for workers. I argue that this is largely due to an abdication of responsibility on the part of their supervisors, and that supervisors are charged with carrying three interlinked moral burdens: first, the duty of promoting safety; second, the duty of ensuring safe experiences are accessible to all; and third, the duty of continuing to learn and improve. To help, I offer a set of safety actions that supervisors can easily implement. I then offer a set of personal reflections on how we should think about failure, accountability, learning, repair, and forgiveness in the scientific workplace. Key words: field safety; field work; equity; inclusion; ethics; supervisor.

Predators balance consequences of climate-change-induced habitat shifts for range-shifting and resident species - Z. T. Wood; I. D. Shepard; S. A. Wissinger; H. S. Greig (Journal of Animal Ecology, 2022)

The effects of environmental variation on daily abundance patterns and diet breadth of bumble bee species - M. Gorchkova (2022)

Does expanding access to cannabis affect traffic crashes? County‐level evidence from recreational marijuana dispensary sales in Colorado - Christian Gunadi (Health Economics, 2022)
AbstractThis article examines the effect of recreational cannabis dispensary sales on traffic crashes by employing difference‐in‐differences model that exploits the variation in the timing of recreational marijuana dispensary entry across counties within Colorado. Using marijuana‐related hospital discharge as a measure of marijuana abuse/misuse, the results indicate a sizable rise in marijuana‐related hospital discharges after the entry of retail cannabis stores. However, there is a lack of evidence that traffic crash incidents are affected by the entry. The preferred estimate suggests that, at 90% confidence level, a large increase in traffic crashes by more than 5% can be ruled out.

Advancements in Measuring and Modeling the Mechanical and Hydrological Properties of Snow and Firn: Multi-sensor Analysis, Integration, and Algorithm Development - Tate G. Meehan (2022)
Estimating snow mechanical properties – such as elastic modulus, stiffness, and strength – is important for understanding how effectively a vehicle can travel over snow-covered terrain. Vehicle instrumentation data and observations of the snowpack are valuable for improving the estimates of winter vehicle performance. Combining in-situ and remotely-sensed snow observations, driver input, and vehicle performance sensors requires several techniques of data integration. I explored correlations between measurements spanning from millimeter to meter scales, beginning with the SnowMicroPenetrometer (SMP) and instruments applied to snow that were designed for measuring the load bearing capacity and the compressive and shear strengths of roads and soils. The spatial distribution of snow’s mechanical properties is still largely unknown. From this initial work, I determined that snow density remains a useful proxy for snowpack strength. To measure snow density, I applied multi-sensor electromagnetic methods. Using spatially distributed snowpack, terrain, and vegetation information developed in the subsequent chapters, I developed an over-snow vehicle performance model. To measure the vehicle performance, I joined driver and vehicle data in the coined Normalized Difference Mobility Index (NDMI). Then, I applied regression methods to distribute NDMI from spatial snow, terrain, and vegetation properties. Mobility prediction is useful for the strategic advancement of warfighting in cold regions. The security of water resources is climatologically inequitable and water stress causes international conflict. Water resources derived from snow are essential for modern societies in climates where snow is the predominant source of precipitation, such as the western United States. Snow water equivalent (SWE) is a critical parameter for yearly water supply forecasting and can be calculated by multiplying the snow depth by the snow density. In this work, I combined high-spatial resolution light detection and ranging (LiDAR) measured snow depths with ground-penetrating radar (GPR) measurements of two-way travel-time (TWT) to solve for snow density. Then using LiDAR derived terrain and vegetation features as predictors in a multiple linear regression, the density observations are distributed across the SnowEx 2020 study area at Grand Mesa, Colorado. The modeled density resolved detailed patterns that agree with the known interactions of snow with wind, terrain, and vegetation. The integration of radar and LiDAR sensors shows promise as a technique for estimating SWE across entire river basins and evaluating observational- or physics-based snow-density models. Accurate estimation of SWE is a means of water security. In our changing climate, snow and ice mass are being permanently lost from the cryosphere. Mass balance is an indicator of the (in)stability of glaciers and ice sheets. Surface mass balance (SMB) may be estimated by multiplying the thickness of any annual snowpack layer by its density. Though, unlike applications in seasonal snowpack, the ages of annual firn layers are unknown. To estimate SMB, I modeled the firn depth, density, and age using empirical and numerical approaches. The annual SMB history shows cyclical patterns representing the combination of atmospheric, oceanic, and anthropogenic climate forcing, which may serve as evaluation or assimilation data in climate model retrievals of SMB. The advancements made using the SMP, multi-channel GPR arrays, and airborne LiDAR and radar within this dissertation have made it possible to spatially estimate the snow depth, density, and water equivalent in seasonal snow, glaciers, and ice sheets. Open access, process automation, repeatability, and accuracy were key design parameters of the analyses and algorithms developed within this work. The many different campaigns, objectives, and outcomes composing this research documented the successes and limitations of multi-sensor estimation techniques for a broad range of cryosphere applications.

Habitat selection in a fluctuating ground squirrel population: Density - dependence and fitness consequences - K. Jenderseck; J. R. Aliperti; D. H. Van Vuren (Ecology and Evolution, 2022)
Investigating individual-based habitat settlement decisions is a central theme in ecology, yet studies that quantify density-dependent habitat selection or tie fitness to resource selection decisions remain rare. We quantified habitat selection in golden-mantled ground squirrels (Callospermophilus lateralis) across two spatial scales (home-range placement, and occurrence within the home range) by using 11 consecutive years of data on individual space use, and we used resource selection functions and multilevel modeling to address how habitat preferences may be influenced by density or linked to fitness outcomes. Squirrels preferred dry meadow over other habitat types (wet meadow, aspen, spruce, and willow) at both spatial scales. Squirrels were more likely to use dry meadow that contained shorter vegetation and vision-enhancing prominences such as rocks ("perches"). The use of dry meadow at each scale was not influenced by changes in density. The use of dry meadow did not lead to increased litter size, pre-hibernation mass, or survival. However, squirrels that experienced a greater number of perches or lower local densities had higher survival rates. Our results suggest that a lack of visual obstruction, probably facilitating detection of predators, drives habitat selection in this system. Surprisingly, squirrels maintained their preference for dry meadow as density increased, and they experienced reduced survival as a result. This work furthers our understanding about the causes and consequences of changes in habitat use, informing wildlife management and conservation.

Causes and consequences of pre-hibernation body mass in golden-mantled ground squirrels (Callospermophilus lateralis) - S. Howland (2022)
Mammals that cope with harsh environmental conditions by hibernating show seasonal variation in body mass, as fat reserves are accumulated during summer and depleted during winter. Hence, pre-hibernation mass is often considered a key phenotypic trait in hibernating species that can be an indicator of future survival and reproductive success. We used 30 years of demographic data from a high-elevation population of golden-mantled ground squirrels (Callospermophilus lateralis) to identify life-history and environmental variables that influence pre-hibernation mass in females, and to determine if pre-hibernation mass influences overwinter survival or subsequent reproduction. Growth curves revealed female-biased size dimorphism, with adult mass not attained until age 2 years, so we considered three age classes of females, juveniles, yearlings, and adults (≥2 years). We found that earlier snow melt during spring is associated with higher pre-hibernation masses of yearlings and adults, and that juveniles emerging earlier from their natal burrows had higher pre-hibernation masses than later-emerging juveniles. Measures of food quantity or quality did not affect pre-hibernation mass for any age class, nor was there an effect of reproductive status. Juvenile females with greater per- hibernation mass were more likely to survive overwinter and reproduce as yearlings, but we found no such effect for yearlings or adult females. We did not find an effect of snow depth or winter duration on either survival or reproduction. Our results indicate that time appears to be the key variable for golden-mantled ground squirrels to acquire sufficient body mass to survive and reproduce, but the effects vary by age class. ii

Statistical framework to assess long-term spatio-temporal climate changes: East River mountainous watershed case study - Boris Faybishenko; Eoin L. Brodie; Bhavna Arora; Dipankar Dwivedi (Stochastic environmental research and risk assessment, 2022)
Evaluation of long-term temporal and spatial climatic change in mountainous regions is a critical challenge because of the interactive effects of multiple land and climatic factors and processes. Here we present the application of the statistical framework to the assessment of changes of climatic conditions, using data from 17 meteorological stations across the East River watershed near Crested Butte, Colorado, USA, and spanning the period from 1966 to 2021. The framework is developed based on (1) a time-series analysis of daily, monthly, and yearly averaged meteorological parameters (tem- perature, relative humidity, precipitation, wind speed, etc.), (2) evaluation and time series analysis of potential evapo- transpiration (ETo), actual evapotranspiration (ET), aridity index (AI), standard precipitation index (SPI) and standard precipitation-evapotranspiration index (SPEI), and (3) a temporal-spatial climatic zonation of the studied area based on the hierarchical clustering and PCA analysis of the SPEI, because the SPEI can be considered an integrative characteristic of the changes of climatic conditions. The Budyko model, with the application of the Penman–Monteith equation for the estimation of ETo, was used to determine the ET. The time series analysis of the AI is used to identify the periods with energy limited and water limited conditions. Hierarchical clustering of site locations for the three temporal segments of the SPEI showed a significant temporal-spatial shifts, indicating that dynamic climatic processes drive zonation patterns. Therefore, the watershed climatic zonation requires periodic re-evaluation based on the structural time series analysis of meteorological and water balance data.

The Effect of Snowmelt Timing on Pollinator Visitation to Subalpine Wildflowers - J. Moloney (2022)
The plant and pollinator mutualism is under increased stress due to climate change, especially in subalpine ecosystems. Climate change is altering the timing of snowmelt in subalpine ecosystems, which changes the flowering phenology and possible the floral abundance of subalpine plants and therefore can impact plant and pollinator interactions. Data gathered at RMBL shows that the date of earliest snowmelt and mean summer temperature are increasing at an unsustainable rate. To better understand the consequences of snowmelt timing on plant-pollinator interactions, an early snowmelt manipulation was performed and pollinator observations were conducted on four subalpine species at the Rocky Mountain Biological Laboratory. The study consists of a numerous pollinator observation sessions in control and early snowmelt plots on 4 species of wildflowers: Delphinium nuttallianum (DENU), Geum triflorum (GETR), Linum lewisii (GETR), and Delphinium barbeyi (DEBA). The four species represent a gradient of phenological flower timing across the growing season beginning with DENU and ending with DEBA. This study aims to allow us to more accurately predict the changes to plant-pollinator interactions in the future as climate change accelerates plant and animal phenology. It was hypothesized that increased likelihood of frost, decreased water availability, and loss of phenological synchrony between wildflowers and pollinators would lead to a lower mean visitation rate and probability of visits in early snowmelt plots compared to the controls. I found that DENU experienced a significantly lower mean visitation rate in early snowmelt plots while LILE experienced significantly higher mean visitation rate. Only DEBA differed significantly the in probability of receiving visit, with a higher probability in early snowmelt. It is possible that as climate change becomes more severe, there will be differential impacts for subalpine plant species and therefore both positive and negative effects on plant and animal interactions. Species that are more resilient to frost and phenological mismatch like LILE may be able to outcompete other more frost and phonologically sensitive species such as DEBA and DENU. More years of study as well as further investigation of species’ reproductive efficacy is needed to support this hypothesis.

Testing for competition, facilitation, and intraguild predation between two co-dominant detritivores: the caddisfly Limnephilus externus and chironomid midges - Mark Ivan Jacobson (2022)
Most living organic material goes through the detrital pathway. Detritovores are incredibly important in ecosystems for the recycling of nutrients and energy. This project explores the inter- and intraspecies relationships between two co-dominant detritovores that inhabit the high-elevation rocky mountain ponds: the caddis fly, Limnephlus externus, and chironomid midges. Specifically, we are trying to determine if there is competition, facilitation, or intraguild predation between Limnephilus externus and chironomid midges. With climate change, the permanent and semipermanent ponds are becoming increasingly temporary. The issue this presents is that L.externus cannot survive in temporary ponds due to their long development time. Therefore, identifying the relationships between the two taxa can help us understand how detrital processing may change with the possible loss of L. externus or shifts in species abundances. For this experiment, we used a response surface design and altered the relative abundances to test for the relationships between the two taxa. Add summary sentence of findings

Balancing model generality and specificity in management-focused habitat selection models for Gunnison sage-grouse - Michael S. O’Donnell (Global Ecology and Conservation, 2022)
Identifying, protecting, and restoring habitats for declining wildlife populations is foundational to conservation and recovery planning for any species at risk of decline. Resource selection analysis is a key tool to assess habitat and prescribe management actions. Yet, it can be challenging to map suitable resource conditions across a wide range of ecological contexts and use the resulting models to identify effective and universal habitat improvement actions. We developed a management-centric modeling approach that sought to balance the need to evaluate the consistency of key habitat conditions and improvement actions across multiple, distinct populations, while allowing context-specific environmental variables and spatial scales to nuance selection responses that form the basis of location-specific management prescriptions. To demonstrate this approach, we developed a set of habitat selection models for Gunnison sage-grouse (Centrocercus minimus), a threatened species under the U.S. Endangered Species Act. Conservation, species recovery, and habitat management efforts are needed in six isolated satellite populations (San Miguel, Crawford, Piñon Mesa, Dove Creek, Cerro Summit-Cimarron-Sims, and Poncha Pass) where environmental conditions differ, and the already small number of birds are declining. We used multi-scale and seasonal resource selection analyses to quantify relationships between environmental conditions and sites used by animals. All models included key habitat variables often altered through management actions to assess their differential influences across models. We found important similarities and differences among satellites, indicating that, although some rules of thumb are generally well-grounded, the consideration of population-specific environmental differences could increase the efficiency of local habitat improvement actions. Sage-grouse also had diverse responses to resource conditions at different scales, indicating that regional spatial (e.g., landscape) and local patch scale can differentially influence expected habitat improvements associated with where such management actions are implemented. Although context variables such as topography cannot be manipulated, sage-grouse associations revealed information that could guide the siting of improvement actions. This approach to balancing management objectives associated with habitat assessment may benefit spatially-structured populations with different environmental contexts and species with complex habitat needs and associations.

Microvirus Genomes Identified in Fecal Samples from Yellow - Bellied Marmots - S. Kraberger; A. Varsani; C. L. Tijerino; Daniel T. Blumstein (Microbiology Resource Announcements, 2022)

High-Resolution Snow-Covered Area Mapping in Forested Mountain Ecosystems Using PlanetScope Imagery - K. Yang; J. Hille Ris Lambers; N. Cristea; A. F. Cannistra; A. John; D. Shean; A. Tan (Remote Sensing, 2022)
Improving high-resolution (meter-scale) mapping of snow-covered areas in complex and forested terrains is critical to understanding the responses of species and water systems to climate change. Commercial high-resolution imagery from Planet Labs, Inc. (Planet, San Francisco, CA, USA) can be used in environmental science, as it has both high spatial (0.7–3.0 m) and temporal (1–2 day) resolution. Deriving snow-covered areas from Planet imagery using traditional radiometric techniques have limitations due to the lack of a shortwave infrared band that is needed to fully exploit the difference in reflectance to discriminate between snow and clouds. However, recent work demonstrated that snow cover area (SCA) can be successfully mapped using only the PlanetScope 4-band (Red, Green, Blue and NIR) reflectance products and a machine learning (ML) approach based on convolutional neural networks (CNN). To evaluate how additional features improve the existing model performance, we: (1) build on previous work to augment a CNN model with additional input data including vegetation metrics (Normalized Difference Vegetation Index) and DEM-derived metrics (elevation, slope and aspect) to improve SCA mapping in forested and open terrain, (2) evaluate the model performance at two geographically diverse sites (Gunnison, Colorado, USA and Engadin, Switzerland), and (3) evaluate the model performance over different land-cover types. The best augmented model used the Normalized Difference Vegetation Index (NDVI) along with visible (red, green, and blue) and NIR bands, with an F-score of 0.89 (Gunnison) and 0.93 (Engadin) and was found to be 4% and 2% better than when using canopy height- and terrain-derived measures at Gunnison, respectively. The NDVI-based model improves not only upon the original band-only model’s ability to detect snow in forests, but also across other various land-cover types (gaps and canopy edges). We examined the model’s performance in forested areas using three forest canopy quantification metrics and found that augmented models can better identify snow in canopy edges and open areas but still underpredict snow cover under forest canopies. While the new features improve model performance over band-only options, the models still have challenges identifying the snow under trees in dense forests, with performance varying as a function of the geographic area. The improved high-resolution snow maps in forested environments can support studies involving climate change effects on mountain ecosystems and evaluations of hydrological impacts in snow-dominated river basins.

Floral phenotypic response of Ipomopsis aggregata and related hybrids to changing soil moisture and nitrogen enrichment - A. Aguilar (2022)
Plants are products of their environment. This is also true for flowers, which can be shaped through abiotic factors that lead to plastic response or natural selection. Both floral morphological traits and volatile organic compounds (VOCs) have the potential to be impacted by environmental conditions. Floral morphology has long been understood to shape pollinator- plant interactions. VOCs emitted by floral tissues compose a plant’s floral scent, which is important for a variety of reproductive-related interactions. Namely, both the concentration and type of VOCs influence the activity of associated pollinators and herbivores. Learning more about floral morphology and VOCs and their response to abiotic conditions is essential due to their significance to plant reproduction and the current trends in global change. To contribute to this growing collection of knowledge, we investigated the effects of differing soil moisture conditions and nitrogen enrichment on the floral traits and VOC profiles of the well- studied Ipomopsis aggregata and related hybrids. To achieve this, we performed two experiments. The first was an observational study which monitored in situ soil moisture and attempted to correlate that to the emissions of compound. The second experiment was a manipulative study where nitrogen fertilizer was added to understand the effects of increased nitrogen on floral traits and VOCs. In response to nitrogen and water treatments we observed increased corolla width within the hybrid population. In terms of VOCs, the main effect was a larger increase in emission of alpha-pinene and beta-myrcene at night when nitrogen was applied, an effect seen only in the I. aggregata population. We did not detect associations of the floral traits with soil moisture. Understanding the effect of environmental conditions on floral traits is essential if we wish to know more about the future of plant-related biotic interactions under climate change.

Within Day Temporal Variation Within Plant-Pollinator Networks - D. Gascon (2022)
Plant-pollinator networks are useful tools for understanding species interactions and biodiversity. The structure of interactions within plant-pollinator networks have provided insight into the potential stability and persistence of ecological communities. Current studies of plant- pollinator networks have primarily focused on a temporally static view. These studies have given insight on general patterns within networks, however the temporally static view they take gives less insight on the various temporal scales at which interactions can change, form, and dissolve. If networks have temporally dependent variables, then constructing networks at different time scales can provide information on structural changes that could be overlooked at different temporal scales. Therefore we want to know if plant-pollinator networks change within a day. What we do know is that plant-pollinator network structure and stability can change over years and within seasons, but we know a lot less about the assembly and disassembly of interactions within days. By focusing on the temporal variation within a day, we improve our understanding of changes to structure and stability of plant-pollinator networks that are meaningful for plant and pollinator ecology. With the use of network metrics like nestedness, connectance, and specialization we can acquire empirical data to show whether there is change to the structure and stability of the network. We find that there seems to be changes occurring between the plant and pollinators, suggesting dynamic aspects.

Comparison of Bee Bowls and Netting for Monitoring Native Bees - M. Mitchell (2022)
This study looked at the differences in bee community composition between estimates obtained from pan traps vs. netting. Comparing species richness, evenness and community composition between the two sampling types from the years 2009-2017 and 2009-2021. Based on a rate of bees caught per hour, without the Bombus genus, bee bowls were more efficient, however, the catch rate of the Bombus genus alone was much higher than the catch rate of the bowls. However, bee bowls still caught a wider range of genus, with the netting still missing around 50 species over the course of the years studied. However, the nets were able to catch larger bodied bees that were missed by the bowls. Overall, it was determined that to get a full understanding of the bee genus/species populations, both bee bowls and netting is needed.

Ant Behavioral Responses to Aphids Colonizing Ligusticum porteri - C. Kennamer (2022)
Ant-aphid mutualisms are keystone interactions that, if altered, have the potential to cause cascading, multitrophic effects on local arthropod and plant communities. In our study system, the flowering stalks of Ligusticum. porteri (Apiaceae) are colonized by the aphid Aphis asclepiadis, which relies on a protection mutualism with ants. We examined the mediating role of phenology in the host plant L. porteri on mutualistic ant behavior in the subalpine zone of the Rocky Mountains in Colorado, USA. To accomplish this, we utilized three tiers of observational data to infer the role of host plant phenology on ant abundance and behavior. First, we compiled six years of census data taken over June through August from 2017-2022 to determine ant abundance during pre-flowering, flowering, and post-flowering phenological stages. In 2022, we recorded focused observations of tending behavior in ants, adding to the census data collected in previous years. Lastly, we used an ethogram to examine effect of advanced, post-flowering phenology in aphid-colonized host plants on a range of 26 different ant behaviors divided among 6 behavioral categories. Ant abundance increased during the flowering stages of L. porteri. Additionally, ant tending behavior also increased during the flowering stages. Finally, during the post flowering stages (fruit initiation and maturation), ants spent the highest proportion of their time on communication, exploration, and grooming behaviors. Increased time spent during these stages on non-tending behaviors such as grooming suggests that ants may budget less time for aphid tending as host plant phenology advances, reducing protective benefits conferred by ants during this time. Taken together, these results suggest that, in years where early season snowmelt leads to advanced phenology of L. porteri, early season aphid colonies arriving in June will encounter host plant conditions that are less conducive to attracting the ants needed to protect them.

Snowmelt Timing Leads to Plasticity and Alters Natural Selection on Leaf Traits in Ipomopsis - Justin Kipness (2022)
Anthropogenic climate change is altering environments, which in turn has the potential to influence plant traits (through phenotypic plasticity) and natural selection. The effect of changing climate on the strength and direction of selection remains unresolved. In this study we quantified the plasticity and strength of selection on vegetative traits of the subalpine herbs Ipomopsis aggregata, Ipomopsis tenuituba, and hybrids. We used long-term data to quantify phenotypic plasticity in these traits and their effects on fitness over 12 years with varying dates of snowmelt in the Colorado Rocky Mountains. We hypothesized that the vegetative traits would be under selection that depended on snowmelt date, which affects early-season water availability and temperature. Specific leaf area (SLA) responded plastically to snowmelt timing, with lower SLA found in early snowmelt years and larger SLA found in late snowmelt years. Natural selection on water use efficiency (WUE) changed based on snowmelt date, with early snowmelt correlating with more positive selection on WUE and late snowmelt correlating with negative selection on WUE. Both plant traits and selection were affected by snowmelt timing and both responded in ways that theoretically should aid in acclimation and adaptation to drier conditions for Ipomopsis. Our results highlight how climate change can impact traits and alter natural selection by modifying abiotic factors such as snowmelt timing.

The Boechera model system for evolutionary ecology - Maggie Wagner; Catherine Rushworth (American Journal of Botany, 2022)

Borgs are giant genetic elements with potential to expand metabolic capacity - Basem Al-Shayeb; Luis E. Valentin-Alvarado; A. Crits-Christoph; Jennifer Doudna; Susan Mullen; Michael J. Wilkins; Rohan Sachdeva; Jacob West-Roberts; M. C. Schoelmerich; Jillian F. Banfield; Kenneth Hurst Williams (Nature, 2022)
Anaerobic methane oxidation exerts a key control on greenhouse gas emissions1, yet factors that modulate the activity of microorganisms performing this function remain poorly understood. Here we discovered extraordinarily large, diverse DNA sequences that primarily encode hypothetical proteins through studying groundwater, sediments and wetland soil where methane production and oxidation occur. Four curated, complete genomes are linear, up to approximately 1 Mb in length and share genome organization, including replichore structure, long inverted terminal repeats and genome-wide unique perfect tandem direct repeats that are intergenic or generate amino acid repeats. We infer that these are highly divergent archaeal extrachromosomal elements with a distinct evolutionary origin. Gene sequence similarity, phylogeny and local divergence of sequence composition indicate that many of their genes were assimilated from methane-oxidizing Methanoperedens archaea. We refer to these elements as 'Borgs'. We identified at least 19 different Borg types coexisting with Methanoperedens spp. in four distinct ecosystems. Borgs provide methane-oxidizing Methanoperedens archaea access to genes encoding proteins involved in redox reactions and energy conservation (for example, clusters of multihaem cytochromes and methyl coenzyme M reductase). These data suggest that Borgs might have previously unrecognized roles in the metabolism of this group of archaea, which are known to modulate greenhouse gas emissions, but further studies are now needed to establish their functional relevance.

Perturbations in plant-pollinator networks: Integrating theoretical and empirical approaches to understand responses to global change - C. N. Morozumi (2022)
Perturbations in plant-pollinator networks: integrating theoretical and empirical

Surface parameters and bedrock properties covary across a mountainous watershed: Insights from machine learning and geophysics - Burke J Minsley; K. Zamudio; B. Carr; Sebastian Uhlemann; Craig Ulrich; Nicola Falco; S. S. Hubbard; Baptiste Dafflon; Haruko M. Wainwright; Kenneth Hurst Williams (Science Advances, 2022)
Bedrock property quantification is critical for predicting the hydrological response of watersheds to climate disturbances. Estimating bedrock hydraulic properties over watershed scales is inherently difficult, particularly in fracture-dominated regions. Our analysis tests the covariability of above- and belowground features on a watershed scale, by linking borehole geophysical data, near-surface geophysics, and remote sensing data. We use machine learning to quantify the relationships between bedrock geophysical/hydrological properties and geomorphological/vegetation indices and show that machine learning relationships can estimate most of their covariability. Although we can predict the electrical resistivity variation across the watershed, regions of lower variability in the input parameters are shown to provide better estimates, indicating a limitation of commonly applied geomorphological models. Our results emphasize that such an integrated approach can be used to derive detailed bedrock characteristics, allowing for identification of small-scale variations across an entire watershed that may be critical to assess the impact of disturbances on hydrological systems.

Understanding the Hydrogeochemical Response of a Mountainous Watershed Using Integrated Surface-Subsurface Flow and Reactive Transport Modeling - Sergi Molins; D. Svyatsky; J. D. Moulton; Ilhan Özgen-Xian; Zexuan Xu; Carl I. Steefel; Dipankar Dwivedi (Water Resources Research, 2022)
Abstract Climate change and other disturbances significantly impact hydrogeochemical exports from mountainous headwater catchments such as the Upper Colorado River Basin. Developing a mechanistic understanding of how the physical and chemical processes interact in time and space in an integrated manner is key to quantifying the future impacts of such disturbances. The hydrogeochemical response of a mountainous catchment in the 2010–2019 period is evaluated quantitatively using a high‐resolution model that simulates integrated hydrology, and transport and reactions for selected solutes and minerals. The model assumes that pyrite is present only at depth while calcite is distributed uniformly, and captures the observed C‐Q reasonably well. Distinct C‐Q dynamics are observed in an average (WY16), a wet (WY17), and a dry (WY18) water year. The model also quantifies the water fraction from surface, shallow and deep groundwater compartments using tracers, and suggests greater groundwater contributions to peak stream discharge in the dry WY18. Results demonstrate that calcium concentrations do not change significantly from year to year, while sulfate shows significant temporal variability. Pyrite dissolution is affected by the changing hydrological drivers where it is enhanced in the dry WY18; calcite dissolution supplements calcium dilution under high flow conditions. The model simulates the reaction hotspots controlled by hydrological conditions, and the spatially‐resolved results show that higher soil saturation and less snowpack occur earlier on the south‐facing side than on the north‐facing side. This is a first‐of‐its‐kind demonstration of a model that integrates hydrologic processes, including evapotranspiration, and reactive transport to enable a predictive understanding of hydrogeochemical exports.

Plant removal across an elevational gradient marginally reduces rates, substantially reduces variation in mineralization - Jeremiah A Henning; Kenna E Rewcastle; Quentin D Read; Aimee T Classen; Nathan J. Sanders; Rebecca E. Irwin (Ecology, 2022)
The loss of aboveground plant diversity alters belowground ecosystem function; yet, the mechanisms underpinning this relationship and the degree to which plant community structure and climate mediate the effects of plant species loss remain unclear. Here, we explored how plant species loss through experimental removal shaped belowground function in ecosystems characterized by different climatic regimes and edaphic properties. We measured plant community composition as well as potential carbon (C) and nitrogen (N) mineralization and microbial extracellular enzyme activity in soils collected from four unique plant removal experiments located along an elevational gradient in Colorado, USA. We found that, regardless of the identity of the removed species or the climate at each site, plant removal decreased the absolute variation in potential N mineralization rates and marginally reduced the magnitude of N mineralization rates. While plant species removal also marginally reduced C mineralization rates, C mineralization, unlike N mineralization, displayed sensitivity to the climatic and edaphic differences among sites, where C mineralization was greatest at the high elevation site that receives the most precipitation annually and contains the largest soil total C pool. Plant removal had little impact on soil enzyme activity. Removal effects were not contingent on the amount of biomass removed annually, and shifts in mineralization rates occurred despite only marginal shifts in plant community structure following plant species removal. Our results present a surprisingly simple and consistent pattern of belowground response to the loss of dominant plant species across an elevational gradient with different climatic and edaphic properties, suggesting a common response of belowground ecosystem function to plant species loss regardless of which plant species are lost or the broader climatic context.

Soil feedbacks and arbuscular mycorrhizal fungi of Linaria vulgaris invasion - L. Novak (2022)
Invasive plants reduce native plant diversity both directly through competition and

BASIN-3D: A brokering framework to integrate diverse environmental data - Madison Burrus; D. S. Christianson; C. Wong; Valerie Hendrix; Deb Agarwal; Charuleka Varadharajan; S. S. Hubbard (Computers & Geosciences, 2022)
Diverse observational and simulation datasets are needed to understand and predict complex ecosystem behavior over seasonal to decadal and century time-scales. Integration of these datasets poses a major barrier towards advancing environmental science, particularly due to differences in the structure and formats of data provided by various sources. Here, we describe BASIN-3D (Broker for Assimilation, Synthesis and Integration of eNvironmental Diverse, Distributed Datasets), a data integration framework designed to dynamically retrieve and transform heterogeneous data from different sources into a common format to provide an integrated view. BASIN-3D enables users to adopt a standardized approach for data retrieval and avoid customizations for the data type or source. We demonstrate the value of BASIN-3D with two use cases that require integration of data from regional to watershed spatial scales. The first application uses the BASIN-3D Python library to integrate time-series hydrological and meteorological data to provide standardized inputs to analytical and machine learning codes in order to predict the impacts of hydrological disturbances on large river corridors of the United States. The second application uses the BASIN-3D Django framework to integrate diverse time-series data in a mountainous watershed in East River, Colorado, United States to enable scientific researchers to explore and download data through an interactive web portal. Thus, BASIN-3D can be used to support data integration for both web-based tools, as well as data analytics using Python scripting and extensions like Jupyter notebooks. The framework is expected to be transferable to and useful for many other field and modeling studies.

Life history consequences of climate change in hibernating mammals: a review - R. Barbier; Stephen T. Nelson; R. Kanaziz; L. M. Aubry; Caitlin P. Wells (Ecography, 2022)
Climatic shifts to warmer and often drier conditions are challenging terrestrial species worldwide. These shifts are occurring more rapidly at higher elevations and latitudes, likely causing disproportionate effects to mammalian hibernators there. While there is some information about how these species' ranges are responding to climatic shifts, we lack an understanding of how climate components are affecting species' life history variation, which is key to individual success and population‐level resilience. We reviewed the literature to identify the direction of life history responses to climate change in mammalian hibernators along three axes: latitudinal, elevational and temporal. We found 39 studies involving 27 species that reported climate effects on our four target life history traits – phenology, body mass/condition and growth, reproduction and survival. We found warmer temperatures are advancing hibernator phenology and increasing reproductive success. By contrast, warming and drying trends are having uncertain effects on body condition, and complex effects on survival – depending on season, age class, latitude and elevation. We found no pattern of significant climate‐trait outcomes by duration or decade of study. More research on drought conditions – particularly in relation to resource availability – would help inform hibernator susceptibility to increased drying trends expected to intensify globally. Notably, our results are highly biased towards small mammal hibernators in Northern Hemisphere alpine/mountain ecosystems, with few long‐term studies conducted on Southern Hemisphere hibernators. This review highlights that phenological shifts constitute one of the most obvious consequences of climate change, yet, the timing of life history events (e.g. timing of migration, reproduction, hibernation) remains poorly understood. Further integration of insights from physiologists, evolutionary biologists and population ecologists working on wild populations will improve our collective understanding of the effects of seasonal climatic shifts on mammalian hibernator life history traits, key drivers of their population‐level persistence.

Modeling snow dynamics and stable water isotopes across mountain landscapes - Reed M. Maxwell; Jeffrey Deems; Alexander W. Newman; W. S. Brown; Matthias Sprenger; Curtis A. Beutler; Kenneth Hurst Williams (Geophysical Research Letters, 2022)
Abstract A coupled hydrologic and snowpack stable water isotope model assesses controls on isotopic inputs across a mountainous basin. Annually, the most depleted isotope conditions occur in the upper subalpine where snow accumulation is high, and rainfall is low. Snowmelt isotopic evolution over time indicates fractionation processes account for <25% snowmelt enrichment. Meltwater isotopic inputs are largely determined by controls on the amount, phase and isotopic mass of precipitation coincident with the ablation period. Effect of vapor loss from the snowpack on d‐excess in snowmelt is a balance between energy and snow‐availability. It is highest above treeline, and in the grass and aspen‐dominated portions of the upper montane where vegetation shading is low. Deep snowpack in conifer forests limit the influence of vapor loss in the subalpine. Wet years reduce the effects of vapor loss on snowmelt across the basin, except in the lower montane where added snowfall bolsters snow‐limited conditions.

Sweet and salty: Pollinators and sodium-enriched nectar - Ethan VanValkenburg (2022)

Three-Dimensional Surface Downwelling Longwave Radiation Clear-Sky Effects in the Upper Colorado River Basin - M. Worden; Jiancong Chen; P. James Dennedy-Frank; Daniel Feldman; Nicola Falco; Baptiste Dafflon; Haruko M. Wainwright (Geophysical Research Letters, 2022)
Abstract In complex terrain, non‐parallel surfaces receive emitted radiation from adjacent surfaces. Qualitatively, where surface skin temperatures and lower tropospheric temperature and humidity are not uniform, the downwelling longwave radiation (DLR) will be determined not just by radiation from the atmosphere above a given location, but also by adjacent surface temperatures. We quantify this three‐dimensional longwave radiative effect over the Upper Colorado River Basin in clear‐sky conditions by calculating surface DLR with observed land‐surface temperatures from ECOSTRESS. We find that this effect is due to terrain‐subtended sky‐view and represents ∼22% of the surface longwave flux, rising to ∼28% and ∼24% in the East and Southeast of the Basin, respectively, and can be >50% in extreme cases. The common omission of this effect in atmospheric radiation models leads to an underestimation of DLR in complex terrain, especially at higher elevations, which has significant implications for mountainous ecohydrology simulations.

Reconsidering the 1922 Colorado River Compact at 100 - Lawrence J. MacDonnell (SSRN Electronic Journal, 2022)

Effects of a range-shifting caddisfly on life histories of a top predator in high elevation ponds - L. Crayton (2022)
Climate change is creating the opportunity for various species to undertake range expansion, both geographically and elevationally. There has been relatively little research into the ecological effects of these climate-driven range expansions on predators, particularly when the new species to a community fills a phenological gap in prey. The opportunity to learn more about these effects comes in a recent range expansion of a caddisfly species, Nemotaulius hostilis, into a well-studied, high elevation pond complex. I explored how this new species might be influencing the growth and life history of a top keystone predator, paedomorphic tiger salamanders. Using mark and recapture and comparing current collected data to that collected before N. hostilis was abundant, I tested how abundance of a new prey source is affecting salamander ecology. By understanding how a range extension influences top predators, we can gain insight into the direct and indirect effects of climate change on aquatic ecosystems.

Watershed zonation through hillslope clustering for tractably quantifying above-and below-ground watershed heterogeneity and functions - Maya Franklin; Burke J Minsley; Michelle Newcomer; Nicholas J. Bouskill; Sebastian Uhlemann; Nicola Falco; S. S. Hubbard; Baptiste Dafflon; Haruko M. Wainwright; Erica R. Siirila-Woodburn; Kenneth Hurst Williams (Hydrology and Earth System Sciences, 2022)
Abstract. In this study, we develop a watershed zonation approach for characterizing watershed organization and functions in a tractable manner by integrating multiple spatial data layers. We hypothesize that (1) a hillslope is an appropriate unit for capturing the watershed-scale heterogeneity of key bedrock-through-canopy properties and for quantifying the co-variability of these properties representing coupled ecohydrological and biogeochemical interactions, (2) remote sensing data layers and clustering methods can be used to identify watershed hillslope zones having the unique distributions of these properties relative to neighboring parcels, and (3) property suites associated with the identified zones can be used to understand zone-based functions, such as response to early snowmelt or drought and solute exports to the river. We demonstrate this concept using unsupervised clustering methods that synthesize airborne remote sensing data (lidar, hyperspectral, and electromagnetic surveys) along with satellite and streamflow data collected in the East River Watershed, Crested Butte, Colorado, USA. Results show that (1) we can define the scale of hillslopes at which the hillslope-averaged metrics can capture the majority of the overall variability in key properties (such as elevation, net potential annual radiation, and peak snow-water equivalent – SWE), (2) elevation and aspect are independent controls on plant and snow signatures, (3) near-surface bedrock electrical resistivity (top 20 m) and geological structures are significantly correlated with surface topography and plan species distribution, and (4) K-means, hierarchical clustering, and Gaussian mixture clustering methods generate similar zonation patterns across the watershed. Using independently collected data, we show that the identified zones provide information about zone-based watershed functions, including foresummer drought sensitivity and river nitrogen exports. The approach is expected to be applicable to other sites and generally useful for guiding the selection of hillslope-experiment locations and informing model parameterization.

Carry-over effects of larval food stress on adult energetics and life history in a nectar-feeding butterfly - Carol L. Boggs (Ecological Entomology, 2022)

Temporal correlations among demographic parameters are ubiquitous but highly variable across species - P. Acker; E. Cam; C. Bonenfant; N. T. Wheelwright; N. G. Yoccoz; Kirsty Macdonald; M. Moiron; A. Nicol-Harper; M. Authier; C. Le Coeur; Christophe Barbraud; Fanie Pelletier; et al. (Ecology Letters, 2022)
Abstract Temporal correlations among demographic parameters can strongly influence population dynamics. Our empirical knowledge, however, is very limited regarding the direction and the magnitude of these correlations and how they vary among demographic parameters and species’ life histories. Here, we use long‐term demographic data from 15 bird and mammal species with contrasting pace of life to quantify correlation patterns among five key demographic parameters: juvenile and adult survival, reproductive probability, reproductive success and productivity. Correlations among demographic parameters were ubiquitous, more frequently positive than negative, but strongly differed across species. Correlations did not markedly change along the slow‐fast continuum of life histories, suggesting that they were more strongly driven by ecological than evolutionary factors. As positive temporal demographic correlations decrease the mean of the long‐run population growth rate, the common practice of ignoring temporal correlations in population models could lead to the underestimation of extinction risks in most species.

Winters are changing: snow effects on Arctic and alpine tundra ecosystems - I. H. Myers-Smith; S. J. Coulson; P. Convey; C. T. Christiansen; B. Elberling; C. Elphinstone; M. Carbognani; S. Bokhorst; J. Boike; G. Blume-Werry; M. P. Björkman; J. W. Bjerke; et al. (Arctic Science, 2022)
Snow is an important driver of ecosystem processes in cold biomes. Snow accumulation determines ground temperature, light conditions, and moisture availability during winter. It also affects the growing season’s start and end, and plant access to moisture and nutrients. Here, we review the current knowledge of the snow cover’s role for vegetation, plant-animal interactions, permafrost conditions, microbial processes, and biogeochemical cycling. We also compare studies of natural snow gradients with snow experimental manipulation studies to assess time scale difference of these approaches. The number of tundra snow studies has increased considerably in recent years, yet we still lack a comprehensive overview of how altered snow conditions will affect these ecosystems. Specifically, we found a mismatch in the timing of snowmelt when comparing studies of natural snow gradients with snow manipulations. We found that snowmelt timing achieved by snow addition and snow removal manipulations (average 7.9 days advance and 5.5 days delay, respectively) were substantially lower than the temporal variation over natural spatial gradients within a given year (mean range 56 days) or among years (mean range 32 days). Differences between snow study approaches need to be accounted for when projecting snow dynamics and their impact on ecosystems in future climates.

How understory bee communities compare to open meadows in the Rocky Mountains - A. Rosenberg (2022)
Forest associated species, bees and otherwise, are among the world's most vulnerable species due human activity such as deforestation. Even though bees are significant to ecosystem health by providing such important services as pollination, basic information on bee biodiversity and factors driving their distributions in temperate coniferous forest ecosystems are relatively scarce. It is likely that there are a minority of bee species that are associated with forest habitats; however, very few have been described. In Colorado, 34% of the landscape is forested. Montane regions such as the Gunnison Valley are predicted to experience the most extreme changes in climate, potentially making bee communities vulnerable. The goals of this research were to determine at which site (meadow or forest) and at what time of day were social and solitary bees most abundant around Gothic, Colorado. We used catch rate as a proxy for abundance. We found that social bees (Bombus spp.) have the same abundance in the meadow as the forest at any time of the day. Solitary bees, on the other hand, are more abundant in the meadow regardless of the time of day. This research project provides a baseline for further investigation of forest associated bees.

“We Are Only Activators” – Virginia Satir and the Mystery of Human Life: A Reflection - Barbara Jo Brothers (2022)
Edited transcription of three lectures, given by Virginia Satir, on the same topic, but presented in three different ways. Lectures were each a part of a month-long seminar given in 1981, 1982, and 1983 during module I of the Avanta Process Community Meetings in Crested Butte, Colorado. [Article copies available for a fee from The Haworth Document Delivery Service: 1-800-342-9678. E-mail address: getinfo@haworthpressinc.com <Website: https://www.haworthpressinc.com>]

An Extreme Number of Sensors in One Spot - Jessica D. Lundquist (Mt. Views Chronicle, 2022)

Future Colorado River Basin Drought and Surplus - Rama Bedri (Hydrology, 2022)
Historical and future drought and surplus periods in the Colorado River basin are evaluated based on eight climate scenarios. Unimpaired streamflow from 17 stations in the Colorado River are evaluated based on U.S. Geological Survey, Bureau of Reclamation, and Coupled Modeled Intercomparison Projection 5 downscaled data from 1950–2099. Representative Concentration Pathway (RCP) 4.5 and 8.5 emission scenarios are considered for four climate models (HadGEM2-ES, CNRM-CM5, CanESM2, MI-ROC5). Drought (surplus) quantities, magnitudes, severities, and water year flows are compared for the historical and future periods. Results indicate that there is a significant difference between the historical record and future projections. The results are not consistent in terms of increase of drought or surplus; however, the intensity (as measured by magnitude and duration) will likely increase for both RCP 4.5 and 8.5. The CanESM2 and CNRM-CM5 models project wetter scenarios, and HadGEM2 and MI-ROC5 models project drier scenarios. For the critical Lees Ferry station, models indicate a chance of higher drought and surplus length and magnitude on the order of two times the historical period. In addition, basin wide flow at Lees Ferry had a shift in the future mean ensemble of approximately 3–10% for the water year. Future hydrologic changes will heighten the need for appropriate management and infrastructure options available to adapt to these changes.

From legacy contamination to watershed systems science: a review of scientific insights and technologies developed through DOE-supported research in water and energy security - David Kaplan; E. J. O’Loughlin; S. L. Painter; T. D. Scheibe; M. I. Boyanov; S. C. Brooks; E. M. Pierce; K. M. Kemner; M. Zavarin; Jillian F. Banfield; X. Chen; Bhavna Arora; et al. (Environmental Research Letters, 2022)
Abstract Water resources, including groundwater and prominent rivers worldwide, are under duress because of excessive contaminant and nutrient loads. To help mitigate this problem, the United States Department of Energy (DOE) has supported research since the late 1980s to improve our fundamental knowledge of processes that could be used to help clean up challenging subsurface problems. Problems of interest have included subsurface radioactive waste, heavy metals, and metalloids (e.g. uranium, mercury, arsenic). Research efforts have provided insights into detailed groundwater biogeochemical process coupling and the resulting geochemical exports of metals and nutrients to surrounding environments. Recently, an increased focus has been placed on constraining the exchanges and fates of carbon and nitrogen within and across bedrock to canopy compartments of a watershed and in river–floodplain settings, because of their important role in driving biogeochemical interactions with contaminants and the potential of increased fluxes under changing precipitation regimes, including extreme events. While reviewing the extensive research that has been conducted at DOE’s representative sites and testbeds (such as the Oyster Site in Virginia, Savannah River Site in South Carolina, Oak Ridge Reservation in Tennessee, Hanford in Washington, Nevada National Security Site in Nevada, Riverton in Wyoming, and Rifle and East River in Colorado), this review paper explores the nature and distribution of contaminants in the surface and shallow subsurface (i.e. the critical zone) and their interactions with carbon and nitrogen dynamics. We also describe state-of-the-art, scale-aware characterization approaches and models developed to predict contaminant fate and transport. The models take advantage of DOE leadership-class high-performance computers and are beginning to incorporate artificial intelligence approaches to tackle the extreme diversity of hydro-biogeochemical processes and measurements. Recognizing that the insights and capability developments are potentially transferable to many other sites, we also explore the scientific implications of these advances and recommend future research directions.

Is flight initiation distance associated with longer-term survival in yellow-bellied marmots ( Marmota flaviventer )? - M. Sanchez (2022)
The distance at which animals move away from threats, flight initiation distance (FID), is often used to study antipredator behavior and risk assessment. Variation in FID is explained by a variety of internal and external biotic and physical factors, including anthropogenic activities. Most prior studies focused on unidentified individuals, so our understanding of the fitness consequences of FID is relatively limited. We asked whether consistent individual differences in variation in flight initiation distance is associated with variation in summer survival or winter survival in an individually- marked population of yellow-bellied marmots (Marmota flaviventer). We found no clear association between flight initiation distance and summer survival or flight initiation distance and winter survival. This suggests that FID decisions, while demonstrably optimizing current survival, may not have longer-term fitness consequences. Our results may have been explained by the relatively modest repeatability of FID or it may have emerged from our attempt to explain longer-term measures of fitness. Future studies of the fitness consequences of personality traits should pay particular attention to the time between which individuality of traits are measured and the fitness consequences are studied.

Building Resilience in the Face of a Dwindling Colorado River - Jane Palmer (Eos, 2022)
Policymakers, industry and conservation professionals, and tribal members explore pathways to a sustainable future for the millions of people reliant on the “lifeblood of the American West.”

Determining changes in floral volatile composition of Ipomopsis aggregata in response to nectar robbing and its associated microorganisms - J. Stryker (2022)
Mutualisms involve complex relationships between multiple types of organisms. Traditionally, mutualisms like pollination have been studied using a pairwise perspective – only focusing on two individual species or groups of species with similar functions involved in the relationship. Including third-party organisms in pollination research allows for a greater understanding of how those mutualisms can persist or break down depending on the different types of interactions. Studying these dynamics are essential to maintaining the ecosystem services provided by pollination and understanding how these mutualisms are able to persist despite interference and exploitation. Ipomopsis aggregata, a hummingbird pollinated montane herb, experiences nectar robbing from native bumble bees, Bombus occidentalis and Bombus mixtus, which reduces hummingbird visitation, pollen transfer, and the reproductive success of I. aggregata. In this study, I examined how nectar robbers and the microbes they disperse alter the chemical phenotype of Ipomopsis aggregata. While volatiles of microbial origin were detected in a subset of microbe-inoculated samples, there were no detectable differences in volatile composition across a combination of robbed and unrobbed flowers with either a sterile sucrose solution, live yeast or bacteria, or dead yeast or bacteria. The lack of distinct volatile differences is likely due to confounding variables including chemical and microbial contamination and the high variability of I. aggregata floral volatiles, along with limited sample sizes. This research offers valuable insights into the difficulties of floral and microbial volatile analysis in the field and suggests that sampling single treated flowers from more controlled populations might reduce contamination and general phenotypic volatile variation.

Review of Vesicular Stomatitis in the United States with Focus on 2019 and 2020 Outbreaks - John Humphreys; Lee W. Cohnstaedt; Robert L. Ewing; Miranda R. Bertram; Angela M. Pelzel‐McCluskey; Luis L. Rodrı́guez; Rachel M. Tell; Robert Keener; Brad Christensen; Debra P. C. Peters (Pathogens, 2021)
Vesicular stomatitis (VS) is a vector-borne livestock disease caused by vesicular stomatitis New Jersey virus (VSNJV) or vesicular stomatitis Indiana virus (VSIV). The disease circulates endemically in northern South America, Central America, and Mexico and only occasionally causes outbreaks in the United States. Over the past 20 years, VSNJV outbreaks in the southwestern and Rocky Mountain regions occurred with incursion years followed by virus overwintering and subsequent expansion outbreak years. Regulatory response by animal health officials is deployed to prevent spread from lesioned animals. The 2019 VS incursion was the largest in 40 years, lasting from June to December 2019 with 1144 VS-affected premises in 111 counties in eight states (Colorado, Kansas, Nebraska, New Mexico, Oklahoma, Texas, Utah, and Wyoming) and was VSIV serotype, last isolated in 1998. A subsequent expansion occurred from April to October 2020 with 326 VS-affected premises in 70 counties in eight states (Arizona, Arkansas, Kansas, Missouri, Nebraska, New Mexico, Oklahoma, and Texas). The primary serotype in 2020 was VSIV, but a separate incursion of VSNJV occurred in south Texas. Summary characteristics of the outbreaks are presented along with VSV-vector sampling results and phylogenetic analysis of VSIV isolates providing evidence of virus overwintering.

Unraveling the ecological and evolutionary impacts of a plant invader on the pollination of a native plant - Wilnelia Recart; Diane R. Campbell (Biological Invasions doi 10.1007/s10530-021-02457-z, 2021)
The results show how the presence of an invasive plant and year-to-year variation in plant-pollinator interactions affect the pollination and components of pollinator-mediated selection in native plants.

Climate and multiple dimensions of plant diversity regulate ecosystem carbon exchange along an elevational gradient - P. Meidi; X. Jing; D. A. Wardle; S. Lavorel; M. K. Sundqvist; C. M. Prager; Jeremiah A Henning; Quentin D Read; Aimee T Classen; Nathan J. Sanders (Ecosphere, 2021)
Abstract The impacts of warming on communities and ecosystems are predicted to be significant in mountain ecosystems because physiological processes, including rates of carbon (C) cycling, are often more temperature‐sensitive in colder environments. Plant biodiversity can also influence C exchange, yet few studies integrate how biotic and abiotic factors may directly or interactively impact ecosystem C flux. Here, we examine the link between simultaneous changes in multiple dimensions of plant diversity and peak growing season ecosystem C uptake across a climatic gradient in the Rocky Mountains, Colorado, USA. We found that taxonomic diversity (species richness), functional diversity (functional evenness), and phylogenetic diversity (mean pairwise distance) were significantly and positively related to peak growing season ecosystem C uptake (i.e., net ecosystem exchange) when considered independently. However, when abiotic and biotic factors were integrated in a structural equation model, only plant phylogenetic diversity was significantly related to C uptake. In addition, we found that actual evapotranspiration (AET—a measure that integrates precipitation and temperature) affected ecosystem C exchange indirectly via its impact on the three dimensions of plant diversity that we examined. These findings highlight complex relationships among key measures of biodiversity and ecosystem C uptake in a rapidly warming ecosystem, and the possible mechanisms that underlie relationships between biodiversity and ecosystem functioning. They also point to the need for integrating multiple dimensions of biodiversity into studies of community and ecosystem ecology.

Archaeological Research Design and Field Methods - David J. Meltzer; Mark Stiger; Brian N. Andrews (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

A hybrid data-model approach to map soil thickness in mountain hillslopes - J. Kwang; Qina Yan; Sebastian Uhlemann; Carl I. Steefel; Nicola Falco; Haruko M. Wainwright; Baptiste Dafflon; S. S. Hubbard (Earth Surface Dynamics, 2021)
Abstract. Soil thickness plays a central role in the interactions between vegetation, soils, and topography, where it controls the retention and release of water, carbon, nitrogen, and metals. However, mapping soil thickness, here defined as the mobile regolith layer, at high spatial resolution remains challenging. Here, we develop a hybrid model that combines a process-based model and empirical relationships to estimate the spatial heterogeneity of soil thickness with fine spatial resolution (0.5 m). We apply this model to two aspects of hillslopes (southwest- and northeast-facing, respectively) in the East River watershed in Colorado. Two independent measurement methods – auger and cone penetrometer – are used to sample soil thickness at 78 locations to calibrate the local value of unconstrained parameters within the hybrid model. Sensitivity analysis using the hybrid model reveals that the diffusion coefficient used in hillslope diffusion modeling has the largest sensitivity among all input parameters. In addition, our results from both sampling and modeling show that, in general, the northeast-facing hillslope has a deeper soil layer than the southwest-facing hillslope. By comparing the soil thickness estimated between a machine-learning approach and this hybrid model, the hybrid model provides higher accuracy and requires less sampling data. Modeling results further reveal that the southwest-facing hillslope has a slightly faster surface soil erosion rate and soil production rate than the northeast-facing hillslope, which suggests that the relatively less dense vegetation cover and drier surface soils on the southwest-facing slopes influence soil properties. With seven parameters in total for calibration, this hybrid model can provide a realistic soil thickness map with a relatively small amount of sampling dataset comparing to machine-learning approach. Integrating process-based modeling and statistical analysis not only provides a thorough understanding of the fundamental mechanisms for soil thickness prediction but also integrates the strengths of both statistical approaches and process-based modeling approaches.

Comparison of Drought Response between Taraxacum officinale and Delphinium nuttallianum - P. Daly (2021)

References - David J. Metlzer; Mark Stiger; Brian N. Andrews (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

The Mountaineer Site - David J. Meltzer; Brian N. Andrews (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

From animals to ecosystem processes: Predicting functional outcomes of climate-driven changes in animal communities through species traits - J. A. Balik (2021)
Functional trait diversity within species assemblages ultimately determines whether or not ecosystem processes are sensitive to shifts in relative abundances or species composition. For example, trait variation suggests detritivores process detritus at different rates and make different relative contributions to whole-assemblage processing, which is therefore likely sensitive to global change-driven shifts in assemblage composition. Here, we address three main questions: 1) what is the magnitude of interspecific variation in detritus processing within the detritivore guild in high-elevation wetlands, 2) which traits drive interspecific variation in processing among larval caddisflies, 3) are larval caddisflies’ single-species effects additive in multi-species assemblages? We used a series of microcosm experiments to quantify species-specific coarse and fine particulate organic matter (CPOM and FPOM) processing for ten closely-related larval caddisfly species and three non-caddisfly species. Next, we compared trait-based models including life history, dietary, and extrinsic trait predictors to determine which intrinsic and extrinsic traits best explain the interspecific variation among the larval caddisflies. Finally, we compared processing by mixed caddisfly assemblages in microcosms and in natural ponds to additive predictions based on individual species processing rates. We found considerable interspecific variation in biomass-specific CPOM (thirteen-fold differences) and FPOM (eight- fold differences) processing. Furthermore, on a mass-specific basis, amphipods and chironomids processed a similar amount of detritus as caddisflies, suggesting the importance of non-shredder taxa for processing CPOM may be greater than previously recognized. Next, the best trait model of CPOM processing included development rate, percent CPOM in the diet, and primary case material. Similarly, the best model for FPOM processing included development rate and percent of total detritus in the diet. Finally, additive predictions were strikingly similar to realized 21 processing in mixed caddisfly assemblages in both microcosms and natural ponds, with the largest difference being a 15% overestimate of CPOM processing in one microcosm experiment. Thus, as global change drives species range shifts, invasions, and extinctions, additivity of species-specific processing suggests that single-species rates may be useful for understanding functional consequences of shifting detritivore assemblages. Furthermore, a trait-based approach to predicting species-specific processing could support preparation of additive estimates of whole-assemblage processing. 22

From the ground up: Building predictions for how climate change will affect belowground mutualisms, floral traits, and bee behavior - A. Rose-Person; Nicole E. Rafferty; A. M. Keeler (Climate Change Ecology, 2021)
Climate change affects species and their interactions, resulting in novel communities and modified ecosystem processes. Through shifts in phenology and distribution, climatic change can disrupt interactions, including those between mutualists. Mutualisms influence the structure and stability of communities and can link species to a common fate. However, research on climate change has focused on pairwise mutualisms, neglecting the higher-order interactions that can arise when species interact with multiple mutualists. We explore the effects of climate change on tripartite interactions involving belowground mutualists, namely soil bacteria and fungi, flowering plants, and pollinators. We outline how climate change is predicted to affect the phenology and distribution of these belowground mutualists, emphasizing the consequent effects on host plant floral traits, plant-pollinator interactions, and bee behavior. We find evidence that warming, advanced snowmelt, and drought are likely to cause phenological and distributional shifts in soil microbes, leading to diminished mutualistic interactions with plants and symbiont switching. Consequently, shifts in flowering phenology, smaller floral displays, and lower quality floral rewards are expected, increasing foraging time and energy demands for bees and altering their floral preferences. Such costs could translate into reduced fitness and novel selection pressures for bees and flowering plants in the short term. We highlight knowledge gaps and ways forward, urging studies on microbe dispersal and phenological cues, experiments that manipulate soil microbe-host plant interactions under simulated climate change conditions, and large-scale field studies across environmental gradients, all with the goal of understanding how climate change will affect soil microbe-plant-pollinator mutualisms.

The Mountaineer Folsom Projectile Point Assemblage - Metin I. Eren; David J. Meltzer (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

The effect of early snowmelt on pollination: A study of four Rocky Mountain subalpine plant species - C. Rigby (2021)
High elevation plant ecosystems are heavily dependent on snowmelt for maintaining spring soil moisture levels. As climate change alters traditional weather patterns and reduces snowpack, snow is melting earlier and altering flowering phenology. With this change in flowering time potentially exposing plants to increased physical stressors including drought and frost, changes in floral characteristics may consequently affect pollination. This study aimed to understand the impacts of climate change-induced early snowmelt on the pollination of four subalpine plant species at the Rocky Mountain Biological Lab of Gothic, Colorado in the summer field season of 2021. I conducted pollinator observations to assess pollination within manipulated early snowmelt plots and control plots upon four wildflower species that flower at different times throughout the summer: Delphinium nuttallianum, Linum lewisii, Hymenoxys hoopesii, and Delphinium barbeyi. I hypothesized that the early snowmelt’s potential stressors upon floral characteristics will lead to lower pollinator visitation rates and a higher probability of visitation than control plants. Plants in the early snowmelt plots had significantly lower pollinator visitation rates and probability of receiving a visit on three of the four species studied. These results are concerning as snowmelt timing continues to advance in alpine and subalpine ecosystems. Decreases in viable pollination can lead to decreases in plant reproduction, potentially leading to falls in population size over time. More research into possible explanations for this decreased rate in visitation, such as how drought stress impacts floral rewards, can help us better understand potential long term consequences that earlier snowmelt will have on subalpine plant and pollinator populations.

A deep learning hybrid predictive modeling (HPM) approach for estimating evapotranspiration and ecosystem respiration - Jiancong Chen; Anh Phuong Tran; Nicola Falco; S. S. Hubbard; Baptiste Dafflon (Hydrology and Earth Systems Science, 2021)
Abstract. Climate change is reshaping vulnerable ecosystems, leading to uncertain effects on ecosystem dynamics, including evapotranspiration (ET) and ecosystem respiration (Reco). However, accurate estimation of ET and Reco still remains challenging at sparsely monitored watersheds, where data and field instrumentation are limited. In this study, we developed a hybrid predictive modeling approach (HPM) that integrates eddy covariance measurements, physically based model simulation results, meteorological forcings, and remote-sensing datasets to estimate ET and Reco in high space–time resolution. HPM relies on a deep learning algorithm and long short-term memory (LSTM) and requires only air temperature, precipitation, radiation, normalized difference vegetation index (NDVI), and soil temperature (when available) as input variables. We tested and validated HPM estimation results in different climate regions and developed four use cases to demonstrate the applicability and variability of HPM at various FLUXNET sites and Rocky Mountain SNOTEL sites in Western North America. To test the limitations and performance of the HPM approach in mountainous watersheds, an expanded use case focused on the East River Watershed, Colorado, USA. The results indicate HPM is capable of identifying complicated interactions among meteorological forcings, ET, and Reco variables, as well as providing reliable estimation of ET and Reco across relevant spatiotemporal scales, even in challenging mountainous systems. The study documents that HPM increases our capability to estimate ET and Reco and enhances process understanding at sparsely monitored watersheds.

Using Fission-Track Radiography Coupled with Scanning Electron Microscopy for Efficient Identification of Solid-Phase Uranium Mineralogy at a Former Uranium Pilot Mill (Grand Junction, Colorado) - Susan M. Hall; Aaron D. Tigar (Geosciences, 2021)
At a former uranium pilot mill in Grand Junction, Colorado, mine tailings and some subpile sediments were excavated to various depths to meet surface radiological standards, but residual solid-phase uranium below these excavation depths still occurs at concentrations above background. The combination of fission-track radiography and scanning electron microscope energy-dispersive X-ray spectroscopy (SEM-EDS) provides a uniquely efficient and quantitative way of determining mineralogic associations of uranium that can influence uranium mobility. After the creation of sample thin sections, a mica sheet is placed on those thin sections and irradiated in a nuclear research reactor. Decay of the irradiated uranium creates fission tracks that can be viewed with a microscope. The fission-track radiography images indicate thin section sample areas with elevated uranium that are focus areas for SEM-EDS work. EDS spectra provide quantitative elemental data that indicate the mineralogy of individual grains or grain coatings associated with the fission-track identification of elevated uranium. For the site in this study, the results indicated that uranium occurred (1) with coatings of aluminum–silicon (Al/Si) gel and gypsum, (2) dispersed in the unsaturated zone associated with evaporite-type salts, and (3) sorbed onto organic carbon. The Al/Si gel likely formed when low-pH waters were precipitated during calcite buffering, which in turn retained or precipitated trace amounts of Fe, As, U, V, Ca, and S. Understanding these mechanisms can help guide future laboratory and field-scale efforts in determining long-term uranium release rates to groundwater.

Ecological factors influence balancing selection on leaf chemical profiles of a wildflower - Kathryn Ghattas; Kasavajhala V. S. K. Prasad; Carrie Olson-Manning; Rose Keith; Judith Wang; Julius Mojica; C. L. Nunez; Lee C-R; Emily Chan; Baosheng Wang; Catherine Rushworth; Maggie Wagner (Nature Ecology & Evolution, 2021)
Balancing selection is frequently invoked as a mechanism that maintains variation within and across populations. However, there are few examples of balancing selection operating on loci underpinning complex traits, which frequently display high levels of variation. We investigated mechanisms that may maintain variation in a focal polymorphism—leaf chemical profiles of a perennial wildflower (Boechera stricta, Brassicaceae)—explicitly interrogating multiple ecological and genetic processes including spatial variation in selection, antagonistic pleiotropy and frequency-dependent selection. A suite of common garden and greenhouse experiments showed that the alleles underlying variation in chemical profile have contrasting fitness effects across environments, implicating two ecological drivers of selection on chemical profile: herbivory and drought. Phenotype–environment associations and molecular genetic analyses revealed additional evidence of past selection by these drivers. Together, these data are consistent with balancing selection on chemical profile, probably caused by pleiotropic effects of secondary chemical biosynthesis genes on herbivore defence and drought response. Evidence for balancing selection acting on loci that control complex traits is limited. Here, the authors show evidence for past selection on chemical profile in a perennial wildflower by two ecological drivers, herbivory and drought, consistent with balancing selection on this trait.

Characterizing the role of phosphorus availability and periphytic algae in the food choice and performance of detritivorous caddisflies (Trichoptera:Limnephilidae) (Freshwater Science, 2021)

The Mountaineer Faunal Remain - Andrew R. Boehm (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

Analyzing Atmospheric Carbonaceous Material Influenced by Wildfires Through Raman Spectroscopy - K. Benton (2021)
In 2020, wildfires burned more acreage in the United States than in the past twenty-one years.1 Boreal wildfires are the cause of ten percent of all annual atmospheric soot in the Northern Hemisphere, which is alarming because soot is detrimental to both human health and environmental health. Some of the negative effects of soot come from the polynuclear aromatic hydrocarbon (PAH) content, which plays a role in the formation of soot. In order to study the structural information of PAH in atmospheric soot from wildfires, a free space Raman spectrometer was built and then used to analyze PAH samples. Raman spectra from anthracene (a PAH), graphite, and o-xylene were collected, showing the spectrometer is in working condition. On collection surfaces, as the height above the fire increased, the areas of dark soot decreased, leading to the belief that the area of observable PAH increases with increasing height. If so, PAH travel farther than soot and spread to greater distances. Suspending the PAH particles in a liquid solution was the most promising method of PAH Raman signal collection and will be improved upon in the future.

Can flowers affect land surface albedo and soil microclimates? - Heidi Steltzer; A. Blazquez-Castro; A. Walwema; Amy M. Iler (International Journal of Biometeorology, 2021)
The phenology of vegetation, namely leaf-out and senescence, can influence the Earth’s climate over regional spatial scales and long time periods (e.g., over 30 years or more), in addition to microclimates over local spatial scales and shorter time periods (weeks to months). However, the effects of flowers on climate and microclimate are unknown. We investigate whether flowers can influence light reflected by the land surface and soil microclimate in a subalpine meadow. We conducted a flower removal experiment with a common sunflower species, Helianthella quinquenervis, for 3 years (2015, 2017, and 2019). The flower removal treatment simulates the appearance of the meadow when Helianthella flowers earlier under climate change and loses its flowers to frost (other plant structures are not damaged by frost). We test the hypotheses that a reduction in cover of yellow flowers leads to a greener land surface, lower reflectance, warmer and drier soils, and increased plant water stress. Flower removal plots are greener, reflect less light, exhibit up to 1.2 °C warmer soil temperatures during the warmest daylight hours, and contain ca. 1% less soil moisture compared to controls. However, soils were warmer in only 2 of the 3 years, when flower abundance was high. Helianthella water use efficiency did not differ between removal and control plots. Our study provides evidence for a previously undocumented effect of flowers on soil microclimate, an effect that is likely mediated by climate change and flowering phenology. Many anthropogenic environmental changes alter landscape albedo, all of which could be mediated by flowers: climate change, plant invasions, and agriculture. This study highlights how further consideration of the effects of flowers on land surface albedo could improve our understanding of the effects of vegetation on microclimate.

Block D - Brian N. Andrews (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

War - John Harner (University Press of Colorado eBooks, 2021)

God - John Harner (University Press of Colorado eBooks, 2021)

Liberty - John Harner (University Press of Colorado eBooks, 2021)

Are vigilance and flight initiation distance correlated in yellow-bellied marmots? - I. DeVito (2021)
Behavioral syndromes are widespread and can have important ecological consequences, since correlations between distinct behaviors shape how animals can respond to changing pressures and can limit behavioral plasticity. Various antipredator behaviors have been identified within behavioral syndromes in many species, and therefore studying the structure of potential behavioral syndromes is important for understanding an animal’s overall behavioral response to predators. This study focused on two antipredator behaviors in yellow-bellied marmots (Marmota flaviventer): time allocation to vigilance during foraging, which represents an individual’s baseline level of wariness, and flight initiation distance (FID), which quantifies the flightiness of an animal in response to a predator. We estimated the correlation between these traits by fitting bivariate model on data collected over 18 years and found a modest correlation between vigilance and FID at the individual level.

Introduction - Mark Stiger; David J. Meltzer; Brian N. Andrews (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

Spatial Characterization of the Large Rock Patterns in Blocks C, X, and Y - Kalanka P. Jayalath; Richard G. Gunst; David J. Meltzer (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

Effects of nectar robbing on the volatile organic compounds and nectar chemistry of intraindividual flowers in Corydalis caseana ssp. brandegeei - M. Long (2021)
Plants are able to change volatile organic compounds in response to herbivory, and these chemicals can communicate with other parts of the same plant and with other plants. Nectar robbers like Bombus mixtus introduce a new microbial community to a flower’s nectar that is different from the one introduced by legitimate pollinators, and this impacts chemical phenotype. This study asks: Does nectar robbing affect the nectar chemistry and volatiles of other flowers on the same inflorescence or the same plant? To answer this question, I compared sugar concentration and volatile organic compound composition of untreated, artificially robbed, and naturally robbed flowers and other flowers on the same Corydalis caseana ssp. brandegeei plant. Sugar concentration is lower in robbed flowers than in unrobbed flowers since rain can enter the nectary through natural or artificial robbing holes, but variation in our data between naturally robbed, artificially robbed, and control plants’ sugar concentrations is more due to confounding variables than a systemic response to robbing. Volatile organic compound composition varies between artificially robbed, naturally robbed, and control plants but does not vary significantly between robbed and unrobbed inflorescences on the same plant.

A Review of Recent Activity in Colorado Water Law - Gary L. Greer (Digital Commons - DU (University of Denver), 2021)
Recent legislative, administrative, and judicial developments have significantly modified the procedures for adjudicating and administrating water rights in Colorado.In this article, Mr. Greer focuses on the procedures outlined in S. 81, noting in particular the shortcomings of S. 81 with respect to the problem of integrating the priorities of surface and ground water users.He also points out the major administrative developments which stem from the conflict between the use of ground and surface water and discusses the requirements of Fellhauer as well as subsequent decisions which deal with the promulgation of rules and regulations for the administration of waters of the state.He concludes by considering the case of United States v. District Court, wherein the Colorado Supreme Court found that the water rights of the United States were subject to the jurisdiction of the Colorado district courts under their plenary powers, and the case of Pikes Peak Golf Club, Inc. v. Kuiper, wherein the court held that nontributary water was not subject to administration by the state engineer.

Geology, Site Formation, and Geochronology - Brooke Morgan; Andrew R. Boehm; Mark Stiger; Brian N. Andrews (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

Predispersal Seed Predation Obscures the Detrimental Effect of Dust on Wildflower Reproduction - V. Ramirez; D. A. Lopez; C. Rosas; Nickolas M. Waser; Mary V. Price (International Journal of Plant Sciences, 2021)

Block A - Mark Stiger (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

Larval Feeding Ability on a Drought-Stressed Invasive Plant - K. Asselin (2021)
Native species are threatened by the introduction of non-native and invasive organisms.

Folsom Point Diggings: The Johnson Site in the Foothills of Larimer County, Colorado - Jason M. LaBelle; Kelton A. Meyer; Raymond V. Sumner (PaleoAmerica, 2021)
The Johnson site is a Folsom occupation in Larimer County, Colorado. T. Russell Johnson discovered the site in 1935, which led to excavations by the Colorado Museum of Natural History in 1936 and later work in 1960 by the University of Wyoming. Little is known of the site due to limited reporting of the excavation and the Folsom assemblage. Our examination of the site collections gathered between 1935 and 1936 reveals an assemblage of 96 items, consisting of Folsom points, preforms, and channel flakes, as well as other tools including end scrapers, gravers, bifaces, and flake tools. Technological analysis of the Folsom points and byproducts of hunting-tool production suggests that site occupants fluted and finished points made from preforms of non-local materials, while additional tools and a few points were made from materials locally available in the Front Range foothills. As such, Johnson represents at minimum a hunting-weaponry-replacement locale.

Habituation or sensitization? Long-term responses of yellow-bellied marmots to human disturbance - K. Uchida; Daniel T. Blumstein (Behavioral Ecology, 2021)
Abstract Continuous exposure to humans causes wildlife to either habituate or sensitize. Although increased tolerance may play an important role in coexistence with humans, the mechanisms and fitness outcomes of long-term changes of tolerance are not fully understood because only a few studies have assessed individual- and population-level responses over many years. We developed a novel predictive framework to study habituation and sensitization to humans and applied it to yellow-bellied marmots (Marmota flaviventer) in areas of high and low human disturbance. We focused on two antipredator behaviors—time allocation to vigilance during foraging to quantify baseline vigilance levels and flight initiation distance (FID)—to quantify subsequent responsiveness to threat. We used the rate of body mass gain during the active season as a fitness outcome. Assessing 15 years’ population and individual-level responses to human disturbances, marmots in highly disturbed colonies allocated more time to vigilance, but this did not change over time. FID decreased on average when they were approached more and also tended to decrease in highly disturbed colonies and over 15 years. Yet, there was individuality in FIDs; marmots that fled at greater distances became sensitized with repeated approaches. Additionally, the marmots in highly disturbed colonies gained less body mass over time compared to conspecifics in less disturbed colonies. These results suggested that, although marmots habituated to humans, long-term human disturbance has negative fitness consequences. Our framework should help wildlife managers evaluate the comprehensive impact of human activities on wildlife.

Understanding pollen specialization in mason bees: a case study of six species - S. Killingsworth; M. McAulay; Jessica R.K. Forrest (Oecologia, 2021)
Many bee species are dietary specialists and restrict their pollen foraging to a subset of the available flowers. However, the reasons for specialization—and the reasons certain plant taxa support numerous specialists—are often unclear. Many bees specialize on the plant family Asteraceae, despite evidence its pollen is a poor food for non-specialists. Here, we studied six mason bee (Osmia) species, including three Asteraceae specialists, to test whether observed pollen-usage patterns reflect larval nutritional requirements, to investigate what aspects of Asteraceae pollen make it unsuitable for non-specialists, and to understand how Asteraceae specialists tolerate their seemingly low-quality diet. We reared larval bees on host and nonhost pollen and found that Asteraceae specialists could develop on nonhost provisions, but that other bees could not survive on Asteraceae provisions. These effects did not seem related to nutritional deficiencies, since Asteraceae provisions were not amino acid deficient, and we found no consistent differences in digestive efficiency among pollen types. However, Aster- aceae specialists completed more foraging flights per larva, generally collected relatively larger provisions, and produced more frass (waste) than the other species, suggesting quantitative compensation for low food quality. Toxins, deficiencies in unmeasured nutrients, or aspects of pollen grain structure might explain poor survival of non-specialists on Asteraceae provisions. Our results suggest that floral host selection by specialist bees is not related to optimizing larval nutrition. We recommend further investigation of host-selection behaviour in adult bees and of pollen digestion in larvae to better under- stand the evolution of bee–flower associations.

Concentration-Discharge Relationships of Dissolved Rhenium in Alpine Catchments Reveal Its Use as a Tracer of Oxidative Weathering - C. R. Lawrence; A. Hayton; R. G. Hilton; M. Dellinger; J. M. Turowski; Patrick Schleppi; M. West; Matthew Winnick; Katharine Maher; Kenneth Hurst Williams (Water Resources Research, 2021)
Abstract Oxidative weathering of sedimentary rocks plays an important role in the global carbon cycle. Rhenium (Re) has been proposed as a tracer of rock organic carbon (OC petro ) oxidation. However, the sources of Re and its mobilization by hydrological processes remain poorly constrained. Here, we examine dissolved Re as a function of water discharge, using samples collected from three alpine catchments that drain sedimentary rocks in Switzerland (Erlenbach and Vogelbach) and Colorado, USA (East River). The Swiss catchments reveal a higher dissolved Re flux in the catchment with higher erosion rates, but have similar [Re]/[Na + ] and [Re]/[SO 4 2− ] ratios, which indicate a dominance of Re from OC petro . Despite differences in rock type and hydro‐climatic setting, the three catchments have a positive correlation between river water [Re]/[Na + ] and [Re]/[SO 4 2− ] and water discharge. We propose that this reflects preferential routing of Re from a near‐surface, oxidative weathering zone. The observations support the use of Re as a proxy to trace rock‐organic carbon oxidation, and suggest it may be a hydrological tracer of vadose zone processes. We apply the Re proxy and estimate CO 2 release by OC petro oxidation of 5.7 +6.6 / −2.0 tC km −2 yr −1 for the Erlenbach. The overall weathering intensity was ∼40%, meaning that the corresponding export of unweathered OC petro in river sediments is large, and the findings call for more measurements of OC petro oxidation in mountains and rivers as they cross floodplains.

Selection of floral traits by pollinators and seed predators during sequential life history stages - Paula Sosenski; Mascha Bischoff; Robert A. Raguso; Heather M. Briggs; Diane R. Campbell (American Naturalist, 2021)
AbstractOrganismal traits often influence fitness via interactions with multiple species. That selection is not necessarily predictable from pairwise interactions, such as when interactions occur during different life cycle stages. Theoretically, directional selection during two sequential episodes (e.g., pollination and seed survival) can generate quadratic or correlational selection for a set of traits that passes both selective filters. We compared strength of selection during pollination versus seed predation in the field and tested whether interactions with multiple species give rise to nonlinear selection on floral traits. We planted common gardens with seeds of two species of Ipomopsis and hybrids at sites where pollination was primarily by hummingbirds or also included hawk moths. We examined selection on six floral traits, including corolla width, sepal width, color, nectar, and two scent compounds. Female fitness (seeds) was broken down into fitness during (1) pollination (seeds initiated) and (2) seed predation (proportion of seeds escaping fly predation). All traits showed evidence of selection. Directional and quadratic selection were stronger during seed initiation than during seed predation. Correlational selection occurred mostly during seed initiation rather than arising from combining species interactions at two points in the life cycle. These results underscore how multispecies interactions can combine to exert selection on trait combinations.

Hidden Processes During Seasonal Isolation of a High-Altitude Watershed - L. L. Lapham; Jessica Buser-Young; Fredrick Colwell; Andrew Thurber; Kenneth Hurst Williams (Frontiers in Earth Science, 2021)
Biogeochemical processes capable of altering global carbon systems occur frequently in Earth’s Critical Zone–the area spanning from vegetation canopy to saturated bedrock–yet many of these phenomena are difficult to detect. Observation of these processes is limited by the seasonal inaccessibility of remote ecosystems, such as those in mountainous, snow- and ice-dominated areas. This isolation leads to a distinct gap in biogeochemical knowledge that ultimately affects the accuracy and confidence with which these ecosystems can be computationally modeled for the purpose of projecting change under different climate scenarios. To examine a high-altitude, headwater ecosystem’s role in methanogenesis, sulfate reduction, and groundwater-surface water exchange, water samples were continuously collected from the river and hyporheic zones (HZ) during winter isolation in the East River (ER), CO watershed. Measurements of continuously collected ER surface water revealed up to 50 μM levels of dissolved methane in July through September, while samples from 12 cm deep in the hyporheic zone at the same location showed a spring to early summer peak in methane with a strong biogenic signature (<65 μM, δ13C-CH4, −60.76‰) before declining. Continuously collected δ 18 O-H 2 O and δ 2 H-H 2 O isotopes from the water column exhibited similar patterns to discrete measurements, while samples 12 cm deep in the hyporheic zone experienced distinct fluctuations in δ 18 O-H 2 O, alluding to significant groundwater interactions. Continuously collected microbial communities in the river in the late fall and early winter revealed diverse populations that reflect the taxonomic composition of ecologically similar river systems, including taxa indicative of methane cycling in this system. These measurements captured several biogeochemical components of the high-altitude watershed in response to seasonality, strengthening our understanding of these systems during the winter months.

Investigating the air temperatures of different taxa in an alpine plant community - M. Hensley (2021)
1. Ecology, like most science, is a rapidly progressing field in which new technologies are constantly being implemented in order to gain a wider and more holistic perspective on plant dynamics. 2. Plants can modulate their temperature via the process of transpiration and shading, which can also lead to modified air and surface temperatures. 3. One of the goals of this research was to investigate whether there is variation in air temperature modification across alpine plant taxa. Because climate change has been shown to have a larger effect on plants at higher elevations, we can use the information from this study to predict how plants will likely cluster in the future as their environment warms. 4. Our results showed minimal variation between the microclimate temperature of the plant and the microclimate temperature of the substrate. Consistently, the plants were in fact cooler than the bare substrate around them but there was no evidence suggesting that certain plant species were able to cool themselves better than others. 5. We didn’t get the results we would have liked to see however, there is still a lot of value and potential that this data holds. This was also a very good preliminary year of conducting thermal research.

Energy Fluxes of Terrestrial and Aquatic Invertebrates in the East River - B. Cleveland (2021)
Climate change is increasing temperatures globally including aquatic habitats like rivers, directly affecting the biology of many invertebrate species. In freshwater ecosystems, snow melt drives rivers in the Rocky Mountains of Colorado. Increasing river temperatures can result in increasing metabolism, and thus prey demand for riverine fishes. Climate change may also affect the temporal dynamics of prey availability by effects on aquatic insect development, which is accelerated under warm conditions, creating mismatching in prey demand and prey abundance. Trout may compensate be feeding on terrestrial prey. Energy flux change throughout the summer season in rivers the temporal dynamics of terrestrial invert fluxes to streams and comparing to the proportion of terrestrial inverts in trout diets. EPT (Ephemeroptera, Plecoptera, and Trichoptera) and Non-EPT (Coleoptera, Hymenoptera, Orthoptera ect.) had close measurements, potential conflicts were weather which was not to be expected. Benthic samples showed the opposite of what was expected because there was an increase over time due to diatom growth. The study is still in progress to become more knowledgeable on how energy fluxes can change River Food webs.

Block C - Brooke Morgan; Brian N. Andrews; David J. Meltzer (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

The Environmental Context - Cathy L Whitlock; Steven D. Emslie; Christy E. Briles; Brian N. Andrews; David J. Meltzer (University Press of Colorado eBooks, 2021)
which, following Aldenderfer (2006), we define as locations at elevations greater than 2,500 meters above sea level (e.g.,

Development of Keras image classification model for use with a study on the effects of recreational trail use on small mammal species richness and activity - D. Novoa (2021)
The recreational trails near the Rocky Mountain Biological Laboratory (RMBL) are an important resource for the community. They generate tourist income for the surrounding area. However, human activity can lead to behavioral and ecological changes in wildlife communities. Utilizing triggered camera traps for small mammals implemented from a study conducted in 2019 and 2020, along with trail cameras, we investigated the effects of recreational trails on small mammals along different habitats. This study developed a Keras image classification model for the rodent activity from bucket camera trapping. The Keras model successfully categorized the diurnal golden-mantled ground squirrel (Callospermophilus lateralis) and least chipmunk (Tamias minimus) but was unable to distinguish between the more similar deer mouse (Peromyscus maniculatus) and montane vole (Microtus montanus). We found that different levels of pedestrian and biker activity did not affect the presence of the small mammals overall. However, a more detailed analysis of the diurnal activity patterns of chipmunks and ground squirrels found that their activity near the trail decreases with increased pedestrian and biker activity. Closer attention should be put on smaller organisms found near trails to monitor how high human activity is leading to lowered small mammal activity.

The benefits of being dominant: Health correlates of male social rank and age in a marmot - S. A. Vydro; R. Ng; John Ward Smith; K. Uchida; Daniel T. Blumstein (Current Zoology, 2021)
The benefits of dominance may not come without costs, particularly for males. For example, the “immunocompetence handicap hypothesis” states that males with enhanced mating success allocate resources to enhance reproductive output at a cost to their current health, whereas the “resource quality hypothesis” predicts that high-ranking males may benefit from increased reproduction and good health. While the predictions from each have been well tested in captive animals and in a variety of highly social primates, fewer studies have been carried out in free-living, facultatively social animals. Using adult male yellow-bellied marmots (Marmota flaviventer), we evaluated predictions of these hypotheses by examining the relationship between social rank and two health indicators--fecal corticosterone metabolite (FCM) levels, and neutrophil/lymphocyte (N/L) ratios--after accounting for variation explained by age, body mass, and seasonality. We found that higher-ranking males tended to have a lower N/L ratio (reflecting good health) than lower-ranking individuals, whereas FCM levels were not significantly related to rank. In addition, heavier male marmots had lower N/L ratios, while body mass was not associated with FCM levels. We also found that older adult males had lower FCM levels (reflecting less physiological stress) but higher N/L ratios than younger adults. Finally, we found that FCM levels decreased as the active season progressed and FCM levels were associated with the time of the day. Overall, our results suggest that socially-dominant male marmots enjoyed better, not worse health in terms of lower N/L ratios. Key words: immunocompetence handicap hypothesis, life history trade-offs, N/L ratio, physiological stress, resource quality hypothesis

Bridging animal personality with space use and resource use in a free-ranging population of an asocial ground squirrel - N. A. Fangue; A. E. Todgham; B. E. Davis; J. R. Aliperti; D. H. Van Vuren (Animal Behaviour, 2021)

The influence of orbital parameters on the North American Monsoon system during the Last Interglacial Period - Nadja Insel; Max Berkelhammer (Journal of Quaternary Science, 2021)
ABSTRACTThe response of summer precipitation in the western United States to climate variability remains a subject of uncertainty. For example, palaeoclimate records indicate the North American Monsoon (NAM) was stronger and spatially more extensive during the Holocene, whereas recent modelling suggests a weakened NAM response to increasing temperatures. These illustrate diverging pictures of the NAM response to warming. Here, we examine summer precipitation in the southwestern US related to Last Interglacial insolation forcing. Using a high‐resolution climate model, we find that Eemian insolation forcing results in overall wetter conditions throughout most of the southwestern US, but significantly drier than present conditions over Arizona. The overall wetter conditions are associated with a northward shift of the anticyclonic circulation aloft and increased moisture in the lower and mid‐troposphere during the Eemian. Increased advection of Gulf of Mexico moisture is responsible for increasing precipitation in New Mexico and the northern edges of the NAM region. Drier conditions over Arizona are likely related to reduced local convection associated with reduced vertical moisture transport. These results highlight the spatial complexity of the NAM response to increasing radiative forcing and allow a better understanding of monsoon dynamics and variability in response to a warming climate.

Analysis of the Potential for Events Similar to the Deadly West Salt Creek Landslide, Grand Mesa Area, Colorado - Paul Michael Santi; Omid Arabnia; Emily Sparks; Edward Emmens (SSRN Electronic Journal, 2021)

Global Warming, Advancing Bloom and Evidence for Pollinator Plasticity from Long-Term Bee Emergence Monitoring - J. Cane (Insects, 2021)
Global warming is extending growing seasons in temperate zones, yielding earlier wildflower blooms. Short-term field experiments with non-social bees showed that adult emergence is responsive to nest substrate temperatures. Nonetheless, some posit that global warming will decouple bee flight and host bloom periods, leading to pollination shortfalls and bee declines. Resolving these competing scenarios requires evidence for bees’ natural plasticity in their annual emergence schedules. This study reports direct observations spanning 12–24 years for annual variation in the earliest nesting or foraging activities by 1–4 populations of four native ground-nesting bees: Andrena fulva (Andrenidae), Halictus rubicundus (Halictidae), Habropoda laboriosa and Eucera (Peponapis) pruinosa (Apidae). Calendar dates of earliest annual bee activity ranged across 25 to 45 days, approximating reported multi-decadal ranges for published wildflower bloom dates. Within a given year, the bee H. rubicundus emerged in close synchrony at multiple local aggregations, explicable if meteorological factors cue emergence. Emergence dates were relatable to thermal cues, such as degree day accumulation, soil temperature at nesting depth, and the first pulse of warm spring air temperatures. Similar seasonal flexibilities in bee emergence and wildflower bloom schedules bodes well for bees and bloom to generally retain synchrony despite a warming climate. Future monitoring studies can benefit from several simple methodological improvements.

Tests for Elevational Gradients in Herbivore Abundance and Plant Resistance in the Rocky Mountain Ecosystem - G. Klens; Kailen A. Mooney (2021)
Community interactions are shaped by the species’ traits dependent on an array of biotic and abiotic factors, yet relatively little is understood about the importance of these factors. Plants have been shown to adapt based on in situ herbivore pressure and abiotic conditions. As herbivore density is theorized to decrease with elevation, plant resistance to herbivores should thus decrease in response. We surveyed grasshopper communities to document changes in herbivore abundance along an elevational gradient and quantified associated shifts in plant palatability through feeding bioassays with grasshoppers. We related grasshopper abundance to elevation at the community level by surveying at 10 sites along an elevational gradient of 488m and related plant palatability to elevation at the species level through feeding bioassays in the lab. In congruence with the decrease in herbivore abundance with elevation, we observed that high elevation plants experienced almost double the herbivore damage as their low elevation counterparts. Our results suggest that high elevation plant communities are less resistant to herbivores and that this shift in palatability may thus be an outcome of the relaxation to local herbivore density and changes in abiotic conditions associated with elevation.

The Colorado East River Community Observatory Data Collection - Erek Alper; David W. Johnson; M. Henderson; Zarine Kakalia; Madison Burrus; Valerie Hendrix; Roelof Versteeg; D. S. Christianson; Eoin L. Brodie; Deb Agarwal; Charuleka Varadharajan; Wenming Dong; et al. (Hydrologic Processes, 2021)
Abstract The U.S. Department of Energy's (DOE) Colorado East River Community Observatory (ER) in the Upper Colorado River Basin was established in 2015 as a representative mountainous, snow‐dominated watershed to study hydrobiogeochemical responses to hydrological perturbations in headwater systems. The ER is characterized by steep elevation, geologic, hydrologic and vegetation gradients along floodplain, montane, subalpine, and alpine life zones, which makes it an ideal location for researchers to understand how different mountain subsystems contribute to overall watershed behaviour. The ER has both long‐term and spatially‐extensive observations and experimental campaigns carried out by the Watershed Function Scientific Focus Area (SFA), led by Lawrence Berkeley National Laboratory, and researchers from over 30 organizations who conduct cross‐disciplinary process‐based investigations and modelling of watershed behaviour. The heterogeneous data generated at the ER include hydrological, genomic, biogeochemical, climate, vegetation, geological, and remote sensing data, which combined with model inputs and outputs comprise a collection of datasets and value‐added products within a mountainous watershed that span multiple spatiotemporal scales, compartments, and life zones. Within 5 years of collection, these datasets have revealed insights into numerous aspects of watershed function such as factors influencing snow accumulation and melt timing, water balance partitioning, and impacts of floodplain biogeochemistry and hillslope ecohydrology on riverine geochemical exports. Data generated by the SFA are managed and curated through its Data Management Framework. The SFA has an open data policy, and over 70 ER datasets are publicly available through relevant data repositories. A public interactive map of data collection sites run by the SFA is available to inform the broader community about SFA field activities. Here, we describe the ER and the SFA measurement network, present the public data collection generated by the SFA and partner institutions, and highlight the value of collecting multidisciplinary multiscale measurements in representative catchment observatories.

How social behaviour and life-history traits change with age and in the year prior to death in female yellow-bellied marmots - Svenja B. Kroeger; Julien G. A. Martin; Daniel T. Blumstein (Philosophical Transactions B, 2021)
Studies in natural populations are essential to understand the evolutionary ecology of senescence and terminal allocation. While there are an increasing number of studies investigating late-life variation in different life-history traits of wild populations, little is known about these patterns in social behaviour. We used long-term individual based data on yellow-bellied marmots (Marmota flaviventer) to quantify how affiliative social behaviours and different life-history traits vary with age and in the last year of life, and how patterns compare between the two. We found that some social behaviours and all life-history traits varied with age, whereas terminal last year of life effects were only observed in life-history traits. Our results imply that affiliative social behaviours do not act as a mechanism to adjust allocation among traits when close to death, and highlight the importance of adopting an integrative approach, studying late-life variation and senescence across multiple different traits, to allow the identification of potential trade-offs. This article is part of the theme issue 'Ageing and sociality: why, when and how does sociality change ageing patterns?'

Modeling geogenic and atmospheric nitrogen through the East River Watershed, Colorado Rocky Mountains - James E. Sample; Taylor Maavara; Fadji Maina; Reed M. Maxwell; K. Dana Chadwick; Michelle Newcomer; Nicholas J. Bouskill; Carl I. Steefel; Wenming Dong; Erica R. Siirila-Woodburn; Kenneth Hurst Williams (PloS one, 2021)
There is a growing understanding of the role that bedrock weathering can play as a source of nitrogen (N) to soils, groundwater and river systems. The significance is particularly apparent in mountainous environments where weathering fluxes can be large. However, our understanding of the relative contributions of rock-derived, or geogenic, N to the total N supply of mountainous watersheds remains poorly understood. In this study, we develop the High-Altitude Nitrogen Suite of Models (HAN-SoMo), a watershed-scale ensemble of process-based models to quantify the relative sources, transformations, and sinks of geogenic and atmospheric N through a mountain watershed. Our study is based in the East River Watershed (ERW) in the Upper Colorado River Basin. The East River is a near-pristine headwater watershed underlain primarily by an N-rich Mancos Shale bedrock, enabling the timing and magnitude of geogenic and atmospheric contributions to watershed scale dissolved N-exports to be quantified. Several calibration scenarios were developed to explore equifinality using >1600 N concentration measurements from streams, groundwater, and vadose zone samples collected over the course of four years across the watershed. When accounting for recycling of N through plant litter turnover, rock weathering accounts for approximately 12% of the annual dissolved N sources to the watershed in the most probable calibration scenario (0–31% in other scenarios), and 21% (0–44% in other scenarios) when considering only “new” N sources (i.e. geogenic and atmospheric). On an annual scale, instream dissolved N elimination, plant turnover (including cattle grazing) and atmospheric deposition are the most important controls on N cycling.

Sources of Controversy in the Law of the Colorado River: An Upper Basin View - Lawrence J. MacDonnell (SSRN Electronic Journal, 2021)

High-discharge disturbance does not alter the seasonal trajectory of nutrient uptake in a montane stream - D. C. West; B. W. Taylor; J. A. Balik (Hydrobiologia, 2021)

Power of place and landscape - J.M. Scott (2021)
This chapter presents and compares three military landscapes encountered by the United States (US) Army’s Second World War 10th Mountain Division, the only wartime US formation dedicated to mountain warfare. The Division’s training in the Rocky Mountains was more than adequate for their task of scaling mountain heights at the centre of the German Wehrmacht Gothic Line in 1945. This chapter is concerned with the military landscapes of specialized mountain training and mountain battle-zones. It proceeds from the view that landscapes are not just a material concept but exist also as memories which can be recalled to navigate physical as well as social landscapes. Signs and symbols associated with and found within the landscape are rarely universal; their meanings are culturally, contextually, and temporally determined.

Yampa River-Colorado River Drainage Divide Origin Determined from Topographic Map Evidence, Southern Routt County, Colorado, USA - Eric Clausen (Open Journal of Geology, 2021)
Detailed topographic map evidence and a new Cenozoic geologic and glacial history paradigm are used to determine the previously unexplained Yampa River-Colorado River drainage divide origin. The Yampa River now flows in a north direction away from the Colorado River (between the Park Range to the east and the Flat Tops region to the west) before turning in a west direction to reach the Unita Mountains where it joins the south-oriented Green River, which eventually joins the southwest-oriented Colorado River. Topographic maps show the Yampa-Colorado River drainage divide is asymmetric with steeper slopes leading to the Colorado River, barbed (south-oriented) tributaries leading to north-oriented Yampa River headwaters (especially near the Yampa River turn to the west), and evidence of a large north-to-south oriented diverging and converging channel complex that preceded present-day drainage routes. Map evidence is interpreted to mean massive south-oriented floods flowed through what are now north-oriented Yampa River headwaters valleys and that headward erosion of a deep west-oriented valley beheaded and reversed those south-oriented flood flow channels to create the north-oriented Yampa River headwaters and the Egeria Park area Yampa-Colorado River drainage divide seen today. Large south-oriented floods leading to the Colorado River (while regional uplift was occurring) are inconsistent with accepted Cenozoic geologic and glacial history paradigm predictions, but are predicted by a newly proposed Cenozoic geologic and glacial history paradigm in which a thick continental ice sheet created a deep “hole” by eroding underlying bedrock and also by causing crustal warping that raised the present-day northern Colorado east-west continental divide as immense south-oriented meltwater floods flowed across it.

From tree to tap: The impacts of climate change on biogeochemical processes during conifer needle distribution and broader implications for water quality in Colorado - Laura T. Leonard (2021)
Recent climate change has contributed to large-scale tree mortality across forested regions in Colorado. As forest health declines, concern for associated terrestrial biogeochemical and hydrologic shifts is mounting. These shifts are related to reduced tree canopy cover, cessation of belowground rhizospheric processes, and increased organic inputs to the system. This can in turn affect terrestrial carbon and nitrogen cycling at the tree scale and downstream water quality. These processes within the forest are complex, however, and the observed changes in soil and stream chemistry can vary across watersheds depending on the land cover, local climate, and location. This dissertation explores biogeochemical processes associated with conifer litter decomposition, a source of terrestrial organic matter contributions, and more broadly the associations between forest health and water quality in Colorado. This work includes field-based experiments beginning at the tree-scale and concludes more broadly with watershed-scale evaluations of water quality. Results revealed the inherent chemistry associated with tree species has a significant influence on soil biogeochemistry during isolated needle decomposition. Further, biogeochemical shifts observed with bark beetle impact are likely driven by other changes (e.g., the cessation of rhizospheric processes and tree canopy loss). Comparisons of the roles of elevation, soil type, seasonal shifts in soil moisture, and snowmelt timing on litter decomposition processes revealed needle presence and seasonal variability of soil moisture are influential in soil carbon release and magnitude. In addition, soil carbon fluxes returned the greatest release associated with more bioavailable litter. Microbial community structure was a key variable that demonstrated sensitivity but also resilience to climate shifts. Extended work beyond the field using historical drinking water reports revealed increased organic disinfection byproducts (DBPs) across certain municipalities of Colorado. The trends correlated with climate variables of reduced total annual days of frost and ice conditions. Closer inspection of these trends in a town of interest revealed long-term decadal and seasonal trends of DBPs associated with spring snowmelt events. This work reveals that as terrestrial-sourced organic matter increases under a changing climate, drinking water facilities should monitor the watershed landscape and source water chemistry to proactively respond to heightened DBP production. iii

Improving predictions of stream CO2 concentrations and fluxes using a stream network model: A case study in the East River watershed, CO, USA - Brian Saccardi Saccardi; Matthew Winnick (Global Biogeochemical Cycles, 2021)
Abstract Inland waters are an important component of the global carbon budget. However, our ability to predict carbon fluxes from stream systems remains uncertain, as p CO 2 varies within streams at scales of 1–100 m. This makes direct monitoring of large‐scale CO 2 fluxes impractical. We incorporate CO 2 input and output fluxes into a stream network advection‐reaction model, representing the first process‐based representation of stream CO 2 dynamics at watershed scales. This model includes groundwater (GW) CO 2 inputs, water column (WC), benthic hyporheic zone (BHZ) respiration, downstream advection, and atmospheric exchange. We evaluate this model against existing statistical methods including upscaling and multiple linear regressions through comparisons to high‐resolution stream p CO 2 data collected across the East River Watershed in the Colorado Rocky Mountains (USA). The stream network model accurately captures GW, evasion, and respiration‐driven p CO 2 variability and significantly outperforms multiple linear regressions for predicting p CO 2 . Further, the model provides estimates of CO 2 contributions from internal versus external sources suggesting that streams transition from GW‐ to BHZ‐dominated sources between 3rd and 4th Strahler orders, with GW, BHZ, and WC accounting for 49.3%, 50.6%, and 0.1% of CO 2 fluxes from the watershed, respectively. Lastly, stream network model atmospheric CO 2 fluxes are 4‐12x times smaller than upscaling technique predictions, largely due to relationships between stream p CO 2 and gas exchange velocities. Taken together, this stream network model improves our ability to predict stream CO 2 dynamics and efflux. Furthermore, future applications to regional and global scales may result in a significant downward revision of global flux estimates.

Cold adaptation drives population genomic divergence in the ecological specialist, Drosophila montana - M. Kankare; R. A. W. Wiberg; V. Tyukmaeva; M. G. Ritchie; A. Hoikkala (Molecular Ecology, 2021)

Seasonal habitat suitability models for a threatened species: the Gunnison sage-grouse - Mindy B. Rice; Kevin Aagaard; Scott Wait; Evan Phillips; Julie R. Stiver; Daniel J. Neubaum; Nathan W. Seward (Wildlife Research, 2021)
Abstract Context The Gunnison sage-grouse (Centrocercus minimus) has experienced range-wide declines and has been listed as Threatened by the USA Fish and Wildlife Service to receive protections under the USA Endangered Species Act. A draft Recovery Plan was recently completed. No seasonal habitat models have been developed for the small isolated populations. Aims To develop a habitat suitability model that was collaboratively developed between modellers and conservation practitioners to predict the probability of use by Gunnison sage-grouse during the breeding and summer seasons in designated occupied critical habitat, and extrapolate to adjacent designated unoccupied critical habitat. Methods We captured, marked and tracked Gunnison sage-grouse in nine different studies spanning 25 years. We used a suite of biotic, abiotic and vegetation local-level and population-scale covariates in a use-available resource selection function to develop models that predict the probability of use by Gunnison sage-grouse. Key results We used 9140 Gunnison sage-grouse locations from 406 individual birds to develop nine resource selection models for occupied habitat and extrapolated model predictions to adjacent unoccupied critical habitat in five small isolated Gunnison sage-grouse populations. A majority of our models validated well. Conclusions We report the first two-season resource use-based habitat suitability models for five of six small isolated Gunnison sage-grouse populations. Because of the unique habitat use by Gunnison sage-grouse in each population, we recommend that resource managers strategically target management actions in individual populations and avoid ‘one-size-fits-all’ habitat management prescriptions. Implications Our models will assist managers in the identification of seasonal habitats within populations to target management actions for Gunnison sage-grouse recovery.

Preface - John Harner (University Press of Colorado eBooks, 2021)

Empirical studies of escape behavior find mixed support for the race for life model - K. Wrensford; W. E. Cooper; J. Gutierrez; Daniel T. Blumstein (Current Zoology, 2021)
Escape theory has been exceptionally successful in conceptualizing and accurately predicting effects of numerous factors that affect predation risk and explaining variation in flight initiation distance (FID, predator-prey distance when escape begins). Less explored is the relative orientation of an approaching predator, prey, and its eventual refuge. The relationship between an approaching threat and its refuge can be expressed as an angle we call the “interpath angle” or “Φ”, which describes the angle between the paths of predator and prey to the prey’s refuge and thus expresses the degree to which prey must run towards an approaching predator. In general, we might expect that prey would escape at greater distances if they must flee toward a predator to reach its burrow. The ‘race for life’ model makes formal predictions about how interpath angle should affect FID. We evaluated the model by studying escape decisions in yellow-bellied marmots Marmota flaviventer, a species which flees to burrows. We found support for some of the model’s predictions, yet the relationship between interpath angle and FID was less clear. Marmots may not assess interpath angle in a continuous fashion; but we found that binning angle into four 45° bins explained a similar amount of variation as models that analyzed angle continuously. Future studies of interpath angle, especially those that focus on how different species perceive relative orientation, will likely enhance our understanding of its importance in flight decisions. Key words: escape behavior, escape trajectory, escape theory, antipredator behavior, race for life model

Variation of Pollen Mass Across Species, Habitat Types, and Time - K. Flores (2021)
Bumble bees are crucial pollinators in both agricultural and wild ecosystems, and as pollinators they rely almost exclusively on floral resources as a source of food. However, in many natural and agricultural areas there has been a decrease in floral diversity and abundance, which in turn has caused nutritional stress for wild pollinators. As a result, many wild bumble bee populations are declining. Therefore, scientists are beginning to research the nutritional requirements of wild bumble bees and the nutrients available in the pollen and nectar they collect. However, there has yet to be any research attempting to quantify the mass of pollen available at the landscape-scale. We addressed this knowledge gap by looking into the variation of pollen mass per flower across species, habitat types, and time. The study was done by collecting flower anthers that have not undergone dehiscence and weighing them out wet and dry to get an estimation of pollen mass. We found that there was significant variation in the pollen mass between species and across the different flowering seasons, but not between habitats. We also found a significant difference in weight between wet and dry anthers, indicating that a majority of anthers consist of mostly water. This research provides a critical but understudied component of pollinator nutritional ecology by quantifying anther mass as an estimate for pollen quantity in the landscape. This research will be used along with pollen macronutrient analyses in the future to build a nutrient landscape available to foraging bees.

Abundance and elevational range shifts of three species of burying beetle in Gunnison County, Colorado and importance of stridulation during reproduction in burying beetles - A. Rawinski (2021)

Testing how density affects caddisfly distribution along a detritus quality gradient - A. E. Adams (2021)
As ecosystems continue to change, the ability to find high-quality habitats is becoming a valuable skill. Caddisflies are often found in pond environments with a variety of habitat qualities, such as food (detritus) quality. Asynarchus nigriculus, being highly mobile and having a unique dietary need for protein are a prime subject for testing the ability of caddisflies to find high-quality habitats when given a range of detritus qualities. A. nigriculus showed a preference for high-quality habitats both individually and in groups. Density was a relatively insignificant factor in their distribution, and aggressive interactions did not increase with density. This indicates that their distribution is based more on the availability of resources than on intraspecific interference interactions.

Comparative study on pollinator visits to high elevation plant communities in Virginia Basin, Gothic, Colorado - D. Gascon (2021)
Plant-pollinator networks are intricate systems that can give insight on a location’s biodiversity and response to environmental changes. By studying pollination networks at different elevations, researchers can evaluate how varying environmental conditions influence how plant and pollinator species interact with one another. In this project, I assessed two plant- pollinator communities in the Virginia Basin at 3500m and at 3350m. Plant-pollinator interactions were recorded by sampling 20x1m transects at each site while censusing flower abundance for five weeks during the summer of 2021. When looking at the overall abundance of flowers at both sites there was no difference between sites abundance or mean visitation per abundance. However, when analyzing the plant species found at both site there was a significant difference between the mean visitation, with plants at the mid site receiving more visits. This difference may be due to harsh conditions at the higher site or the greater plant diversity there, which results in the dilution of visits to each plant species. Further studies could look into how other factors like weather variables and climate change affect these plant-pollinator communities.

Water - John Harner (University Press of Colorado eBooks, 2021)

How do humans impact yellow-bellied marmots? An integrative analysis - J. Nelson; E. Foli; R. Monclus; L. Chunwang; A. Morgan; Daniel T. Blumstein (Applied Animal Behaviour Science, 2021)
While many studies document specific human impacts on the behaviour and physiological responses of wildlife to humans

The genome of the Margined White butterfly (Pieris macdunnoughii): sex chromosome insights and the power of polishing with PoolSeq data - Y. Okamura; Hans Ulrich Vogel; C. W. Wheat; Rachel A Steward; Carol L. Boggs (Genome Biology and Evolution, 2021)
We report a chromosome-level assembly for Pieris macdunnoughii, a North American butterfly whose involvement in an evolutionary trap imposed by an invasive Eurasian mustard has made it an emerging model system for studying maladaptation in plant-insect interactions. Assembled Downloaded from https://academic.oup.com/gbe/advance-article/doi/10.1093/gbe/evab053/6178793 by guest on 15 April 2021 using nearly 100X coverage of Oxford Nanopore long reads, the contig-level assembly comprised 106 contigs totaling 316,549,294 bases, with an N50 of 5.2Mb. We polished the assembly with PoolSeq Illumina short-read data, demonstrating for the first time the comparable performance of individual and pooled short reads as polishing datasets. Extensive synteny between the reported contig-level assembly and a published, chromosome-level assembly of the European butterfly Pieris napi allowed us to generate a pseudo-chromosomal assembly of 47 contigs, placing 91.1% of our 317 Mbp genome into a chromosomal framework. Additionally, we found support for a Z chromosome arrangement in P. napi, showing that the fusion event leading to this rearrangement predates the split between European and North American lineages of Pieris butterflies. This genome assembly and its functional annotation lay the groundwork for future research into the genetic basis of adaptive and maladaptive egg-laying behavior by P. macdunnoughii, contributing to our understanding of the susceptibility and responses of insects to evolutionary traps.

Experimental Validation of Biophysical Models of Tiger Salamanders ( Ambystoma mavortium nebulosum ) - L. Rowley; K. E. Reider (2021)
Arizona tiger salamanders (Ambystoma mavortium nebulosum) can thrive in a large variety of environments including high elevation ecosystems where climate change conditions are most drastic. Accurate biophysical models of the water loss and operative temperature for A. m. nebulosum can be used as tools to investigate two major environmental constraints faced by amphibians under climate change: exposure to water loss and extreme temperatures. The purpose of this study was to validate plaster biophysical models to use in future Arizona tiger salamander ecophysiology research. Objective 1 was to construct a constant humidity chamber for the biophysical model validation experiments. The chamber maintained a 55 ± 5% relative humidity at 17 ℃ with a saturated magnesium chloride solution. Objective 2 was to compare model water loss and temperature to live tiger salamanders in the constant humidity chamber. A model and a live salamander were placed into individual mesh containers in the constant humidity chamber. The water loss and temperature change of models and salamanders were tracked during the 150- minute trials. The loss of water rate proved to be insignificant between the models and salamanders validating this biophysical model. Future field experiments will be able to use these models, but modifications to the models can be used to improve upon their design.

Changes in hunting season regulations (1870s–2019) reduce harvest exposure on greater and Gunnison sage-grouse - Jacob D. Hennig; Courtney J. Duchardt; Jeffrey L. Beck; Jonathan B. Dinkins (PLOS ONE, 2021)
Hunter harvest is a potential factor contributing to population declines of sage-grouse (Centrocercus spp.). As a result, wildlife agencies throughout western North America have set increasingly more conservative harvest regulations over the past 25 years to reduce or eliminate hunter success and concomitant numbers of harvested greater (C.urophasianus) and Gunnison (C.minimus) sage-grouse. Sage-grouse hunting has varied widely over time and space, which has made a comprehensive summary of hunting management challenging. We compiled data on harvest regulations among 11 western U.S. states and 2 Canadian provinces from 1870–2019 to create a timeline representative of hunting regulations. We compared annual harvest boundaries and area-weighted average hunting regulations, 1995–2018, relative to administrative boundaries and areas of high probability of sage-grouse occupation. We also summarized estimated numbers of birds harvested and hunters afield, 1995–2018, across both species’ ranges. From 1995–2018, there was a 30% reduction in administrative harvest boundaries across the greater sage-grouse range compared to a 16.6% reduction in area open to harvest within 8 km from active leks. Temporary closures occurred in response to wildfires, disease outbreaks, low population numbers, and two research projects; whereas, permanent closures primarily occurred in small populations and areas on the periphery of the species distribution. Similarly, area-weighted possession limits and season length for greater sage-grouse decreased 52.6% and 61.0%, respectively, while season start date stayed relatively stable (mean start date ~259 [mid-September]). In contrast, hunting of the now federally-threatened Gunnison sage-grouse ended after 1999. While restrictions in harvest regulations were large in area, closures near areas of high greater sage-grouse occupancy were relatively smaller with the same trend for Gunnison sage-grouse until hunting ceased. For greater sage-grouse, most states reduced bag and possession limits and appeared to adhere to recommendations for later and shorter hunting seasons, reducing potential for additive mortality.

Producer-scrounger relationships in yellow-bellied marmots - A. W. Evans; Dana M. Williams; Daniel T. Blumstein (Animal Behaviour, 2021)

How does incorporating microclimate data into ecological niche models change our estimates of the climatic niche of vascular plant species? - A. Wells (2021)

Experimental test of the ability of plants to regulate their temperatures under climate change: Using transplanted communities, thermal imaging, and arcGIS across an elevation gradient - S. Buchholtz (2021)
The question of thermoregulation in plants is increasingly important in a rapidly changing climate. Plants have long been considered poikilotherms, where internal temperatures are decided by the external environment. However, observations show that plants have some ability to thermoregulate. If plants are heterotherms, then they have the potential to be more resilient to the warming climate. This project seeks to examine thermoregulation through technology, specifically FLIR imagery. At three different sites in Washington Gulch, plants were moved to examine the effects of a warmer or cooler environment. This project will use thermal imagery on those transplants in order to study how the temperature of plant communities change when moved to a new climate.

Investigating the comparison between bird diversity and apex aquatic predators in sub-alpine beaver ponds - A. Haeseler (2021)
Predation of native salamanders by non-native trout in Colorado is a wildlife concern. Understanding the dynamics of how the different species interact is important. Cascade effects in the environment are caused by declines of species in a community. Birds, fish, and amphibians are deeply connected, therefore observing birds may help understand the ecosystem. Bird diversity is a crucial indicator to understand environmental changes and health. The research focused on the effects of different apex aquatic predators and the number of different bird species near beaver ponds. Point counts were conducted to observe birds visually and aurally for 15 minutes. The comparison between pond type and number of different species was significant, suggesting that different aquatic predators may affect bird communities. In future research, analyzing the tree canopy and pond depth would provide a useful distinction of each pond.

Chemical Variation among Castes, Female Life Stages and Populations of the Facultative Eusocial Sweat Bee Halictus rubicundus (Hymenoptera: Halictidae) - R. J. Paxton; S. Schulz; I. Steitz; M. Ayasse; I. Steitz; S. Schulz; M. Ayasse; R. J. Paxton (Journal of Chemical Ecology, 2021)
In eusocial insects, chemical communication is crucial for mediating many aspects of social activities, especially the regulation of reproduction. Though queen signals are known to decrease ovarian activation of workers in highly eusocial species, little is known about their evolution. In contrast, some primitively eusocial species are thought to control worker reproduction through physical aggression by the queen rather than via pheromones, suggesting the evolutionary establishment of chemical signals with more derived sociality. However, studies supporting this hypothesis are largely missing. Socially polymorphic halictid bees, such as Halictus rubicundus, with social and solitary populations in both Europe and North America, offer excellent opportunities to illuminate the evolution of caste-specific signals. Here we compared the chemical profiles of social and solitary populations from both continents and tested whether (i) population or social level affect chemical dissimilarity and whether (ii) caste-specific patterns reflect a conserved queen signal. Our results demonstrate unique odor profiles of European and North American populations, mainly due to different isomers of n-alkenes and macrocyclic lactones; chemical differences may be indicative of phylogeographic drift in odor profiles. We also found common compounds overproduced in queens compared to workers in both populations, indicating a potential conserved queen signal. However, North American populations have a lower caste-specific chemical dissimilarity than European populations which raises the question if both use different mechanisms of regulating reproductive division of labor. Therefore, our study gives new insights into the evolution of eusocial behavior and the role of chemical communication in the inhibition of reproduction.

Developing Parameter Constraints for Radar-based SWE Retrievals (UWSpace (University of Waterloo), 2021)
Terrestrial snow is an important freshwater reservoir with significant influence on the climate and energy balance. It exhibits natural spatiotemporal variability which has been enhanced by climate change, thus it is important to monitor on a large scale. Active microwave, or radar remote sensing has shown frequency-dependent promise in this regard, however, interpretation remains a challenge. The aim of this thesis was to develop constraints for radar based SWE retrievals which characterize and limit uncertainty with a focus on the underlying physical processes, snowpack stratigraphy, the influence of vegetation, and effects of background scattering.
\nThe University of Waterloo Scatterometer (UWScat) was used to make measurements at 9.6 and 17.2 GHz of snow and bare ground in a series of field-based campaigns in Maryhill and Englehart, ON, Grand Mesa, CO (NASA SnowEx campaign, year 1), and Trail Valley Creek, NT. Additional measurements from Tobermory, ON, and Churchill, MB (Canadian Snow and Ice Experiment) were included. The Microwave Emission Model for Layered Snowpacks, Version 3, adapted for backscattering (MEMLS3&a) was used to explore snowpack parameterization and SWE retrieval and the Freeman-Durden three component decomposition (FD3c) was used to leverage the polarimetric response.
\nPhysical processes in the snow accumulation environment demonstrated influence on regional snowpack parameterization and constraints in a SWE retrieval context with a single-layer snowpack parameterization for Maryhill, ON and a two-layer snowpack parameterization for Englehart, ON resulting in a retrieval RMSE of 21.9 mm SWE and 24.6 mm SWE, respectively. Use of in situ snow depths improved RMSE to 12.0 mm SWE and 10.9 mm SWE, while accounting for soil scattering effects further improved RMSE by up to 6.3 mm SWE. At sites with vegetation and ice lenses, RMSE improved from 60.4 mm SWE to 21.1 mm SWE when in situ snow depths were used. These results compare favorably with the common accuracy requirement of RMSE ≤ 30 mm and underscore the importance of understanding the driving physical processes in a snow accumulation environment and the utility of their regional manifestation in a SWE retrieval context. A relationship between wind slab thickness and the double-bounce component of the FD3c in a tundra snowpack was introduced for incidence angles ≥ 46° and wind slab thickness ≥ 19 cm. Estimates of wind slab thickness and SWE resulted in an RMSE of 6.0 cm and 5.5 mm, respectively. The increased double-bounce scattering was associated with path length increase within a growing wind slab layer. Signal attenuation in a sub-canopy SWE retrieval was also explored. The volume scattering component of the FD3c yielded similar performance to forest fraction in the retrieval with several distinct advantages including a real-time description of forest condition, accounting for canopy geometry without ancillary information, and providing coincident information on forest canopy in remote locations.
\nOverall, this work demonstrated how physical processes can manifest regional outcomes, it quantified effects of natural inclusions and background scattering on SWE retrievals, it provided a means to constrain wind slab thickness in a tundra environment, and it improved characterization of coniferous forest in a sub-canopy SWE retrieval context. Future work should focus on identifying ice and vegetation conditions prior to SWE retrieval, testing the spatiotemporal validity of the methods developed herein, and finally, improving the integration of snowpack attenuation within retrieval efforts.

Topographic Map Analysis of the North Platte River-South Platte River Drainage Divide Area, Western Larimer County, Colorado, USA Eric Clausen - Eric Clausen (Earth Science Research, 2021)
The United States Supreme Court settled legal disputes concerning four different Larimer County (Colorado) locations where water is moved by gravity across the high elevation North Platte-South Platte River drainage divide, which begins as a triple drainage divide with the Colorado River at Thunder Mountain (on the east-west continental divide and near Colorado River headwaters) and proceeds in roughly a north and northeast direction across deep mountain passes and other low points (divide crossings) first as the Michigan River (in the North Platte watershed)-Cache la Poudre River (in the South Platte watershed) drainage divide and then as the Laramie River (in the North Platte watershed)-Cache la Poudre River drainage divide. The mountain passes and nearby valley and drainage route orientations and other unusual erosional features can be explained if enormous and prolonged volumes of south-oriented water moved along today’s north-oriented North Platte and Laramie River alignments into what must have been a rising mountain region to reach south-oriented Colorado River headwaters. Mountain uplift in time forced a flow reversal in the Laramie River valley while flow continued in a south direction along the North Platte River alignment only to be forced to flow around the Medicine Bow Mountains south end and then to flow northward in the Laramie River valley and later to be captured by headward erosion of the east-oriented Cache la Poudre River-Joe Wright Creek valley (aided by a steeper gradient and less resistant bedrock). Continued uplift next reversed flow on the North Platte River alignment to create drainage routes seen today. While explaining Larimer County North Platte-South Platte drainage divide area topographic map drainage system and erosional landform evidence this interpretation requires a completely different Cenozoic history than the geologic history geologists usually describe.

Demographic Consequences of Phenological Shifts in Response to Climate Change - E. Post; Jessica R.K. Forrest; Amy M. Iler; Paul J. CaraDonna (Annual Review of Ecology, Evolution, and Systematics, 2021)

Do microorganisms obey macroecological rules? - S. E. Turner; A. Padukone; D. Yaffar; K. S. Sheldon; R. Swenie; C. Winfrey; J. Dickey; K. K. Beals; Stephanie N. Kivlin (Authorea, 2021)
Understanding the factors controlling the relative abundance, distribution, and diversity of organisms is a fundamental challenge in ecology. For plants and animals, macroecological rules have been developed that describe these large-scale distributional patterns and attempt to explain the underlying physiological and ecological processes behind them. Similarly, microorganisms exhibit patterns in relative abundance, distribution, and diversity across space and time, yet it remains unclear the extent to which microorganisms follow macroecological rules initially developed for macroorganisms. With rapid advancements in sequencing technology, we have seen a recent increase in microbial studies that utilize macroecological frameworks. Here we review and synthesize these macroecological microbial studies with two main objectives: (1) to determine to what extent macroecological rules explain the distribution of host-associated and free-living microorganisms, and (2) to understand which environmental factors and stochastic processes may explain these patterns among microbial clades (archaea, bacteria, fungi, protists) and habitats (host-associated and free living; terrestrial and aquatic). Our review is the first, to our knowledge, that examines whether or not the same environmental drivers contribute to similar trends to macroecological studies when rules are upheld for microorganisms. Further, we outline several outstanding questions and recommendations for future studies in microbial ecology.

Biotic interactions at species’ range limits in a changing climate - I. D. Shepard (2021)

Effects of early snowmelt on plant phenophase timing and duration across an elevation gradient - Chelsea Wilmer (2021)
EFFECTS OF EARLY SNOWMELT ON PLANT PHENOPHASE TIMING AND DURATION ACROSS AN

The Influence of Summer Precipitation and Temperature on Golden Mantled Ground Squirrel Pup Foraging. - M. Nickson (2021)
Golden-mantled ground squirrels (GMGS) at the Rocky Mountain Biological Laboratory (RMBL) spend the majority of the year, from October to May, hibernating in order to save energy during the winter seasons in Gothic, Colorado. Once the winter season is over, the squirrels emerge from their burrows and spend spring and summer foraging in preparation for next winter. Foraging behavior is highly important during these months since food only starts to become available when snow melts, stimulating green vegetation growth. However, vegetation quality may depend on weather conditions: drier years may decrease vegetation quality, while wetter years may increase vegetation quality. Though behavioral flexibility is one of the most common modes of response across most mammal species, there is a lack of knowledge on how acute climate stress changes animals’ foraging behavior. Behavioral flexibility is the ability of having diverse behavioral traits, which is important for species to adapt to any changes and survive in their environment. In conclusion, small mammals such as the golden-mantled ground squirrel, must constantly balance foraging and avoiding factors that increase mortality, including disadvantageous weather conditions. They can modify foraging patterns and overall daily activity when the weather changes (Stokes, 2001). Foraging activity was greatly affected by precipitation and temperatures in the month of July. With hotter temperatures more common in the future, I expect this effect to cause a negative shift in the pups foraging behavior, causing them to have to adapt in new ways. Key Words: Golden-Mantled Ground Squirrel, Temperature, Precipitation, Behavioral Flexibility, Dry/Wet Years

Open-top warming chambers reduce animal pollination of two subalpine herbs - C. Adamson; Amy M. Iler (Journal of Pollination Ecology, 2021)
Open top chambers (OTCs) are a popular method for studying the biological effects of climate change through passive heating, but their effects on biotic interactions are poorly understood, especially for pollination. Here we use the subalpine plants Delphinium nuttallianum and Potentilla pulcherrima to examine the possibility that the effects of OTCs on plant reproduction are not the result of warming but rather OTCs acting as barriers to pollinator movement. Pollinator observations were conducted and stigmas collected from plants inside and outside of OTCs in a meadow in the Rocky Mountains of Colorado, USA. Very few visitors were observed inside of OTCs, which led to severe reductions in visitation rates, by 92% in Delphinium and 85% in Potentilla. The number of conspecific pollen grains on stigmas was 73% lower in OTCs for Delphinium but not Potentilla, likely because it is capable of autogamous self-pollination. This study clearly shows that OTCs can reduce animal pollination, which is also likely to reduce plant reproductive output of outcrossing plants via decreases in the quantity or quality of pollen. OTCs may therefore confound effects of warming on plant reproduction with pollination effects. Although the unintended effects of OTCs on abiotic conditions are well-studied, this study highlights that their effects on biotic interactions require further investigation.

Estimation of Evapotranspiration Rates and Root Water Uptake Profiles From Soil Moisture Sensor Array Data - W. Li; H. Zhou; D. M. Tartakovsky; Qina Yan; Roelof Versteeg; Yuxin Wu; Haruko M. Wainwright; Baptiste Dafflon (Water Resources Research, 2021)
AbstractEvapotranspiration is arguably the least quantified component of the hydrologic cycle. We propose two complementary strategies for estimation of evapotranspiration rates and root water uptake profiles from soil‐moisture sensor‐array data. One is our implementation of ensemble Kalman filter (EnKF); it treats the evapotranspiration sink term in the Richards equation, rather than soil moisture, as the observable to update. The other is a maximum likelihood estimator (MLE) applied to the same observable; it is supplemented with the Fisher information matrix to quantify uncertainty in its predictions. We use numerical experiments to demonstrate the accuracy and computational efficiency of these techniques. We found our EnKF implementation to be two orders of magnitude faster than either the standard EnKF or MLE, and our MLE procedure to require an order of magnitude fewer iterations to converge than its counterpart applied to soil moisture. These findings render our methodologies a viable and practical tool for estimation of the root water uptake profiles and evaporation rates, with the MLE technique to be used when the prior knowledge about evapotranspiration at the site is elusive.

Probabilistic Evaluation of Geoscientific Hypotheses With Geophysical Data. Application to Electrical Resistivity Imaging of a Fractured Bedrock Zone - Alex Miltenberger; T. Mukerji; Lijing Wang; Sebastian Uhlemann; Baptiste Dafflon; Haruko M. Wainwright; Kenneth Hurst Williams (Journal of Geophysical Research, 2021)
AbstractAs climate changes and populations grow, groundwater sustainability is becoming increasingly important. Hydrogeologic models, which are based on a conceptual understanding of the subsurface, are crucial tools for informing decisions. Conceptual models of the subsurface incorporate knowledge of geological processes, and, frequently, observations from geophysical data into a common subsurface parameterization where the parameters may still be uncertain. Many methods exist to test how different conceptual subsurface parameterizations compare to geophysical data, but a frequent problem in hydrogeologic model development occurs when multiple geological phenomena could explain a single subsurface parameterization. In this work, we present a framework for testing geological hypotheses in conditions where a geological feature is observed in geophysical data, but its physical characteristics are uncertain. The framework uses Popper‐Bayes methods developed in previous studies, and is applied to study a fractured bedrock zone in a mountainous watershed in southwest Colorado. First, we propose six hypotheses based on the geological history of the watershed. Then, using the proposed Popper‐Bayes approach, we demonstrate that two of the hypotheses are inconsistent with the electrical resistivity tomography data. Finally, we discuss the importance of the prior model, and in what other scenarios the framework can be applied to.

DynaMETE: a hybrid MaxEnt-plus-mechanism theory of dynamic macroecology - M. Brush; K. Umemura; John Harte (Ecology Letters, 2021)
John Harte,1,2,3* The Maximum Entropy Theory of Ecology (METE) predicts the shapes of macroecological met- Kaito Umemura4 and rics in relatively static ecosystems, across spatial scales, taxonomic categories and habitats, using Micah Brush5 constraints imposed by static state variables. In disturbed ecosystems, however, with time-varying state variables, its predictions often fail. We extend macroecological theory from static to dynamic by combining the MaxEnt inference procedure with explicit mechanisms governing disturbance. In the static limit, the resulting theory, DynaMETE, reduces to METE but also predicts a new scaling relationship among static state variables. Under disturbances, expressed as shifts in demo- graphic, ontogenic growth or migration rates, DynaMETE predicts the time trajectories of the state variables as well as the time-varying shapes of macroecological metrics such as the species abundance distribution and the distribution of metabolic rates over individuals. An iterative pro- cedure for solving the dynamic theory is presented. Characteristic signatures of the deviation from static predictions of macroecological patterns are shown to result from different kinds of distur- bance. By combining MaxEnt inference with explicit dynamical mechanisms of disturbance, Dyna- METE is a candidate theory of macroecology for ecosystems responding to anthropogenic or natural disturbances.

The influence of human recreational trail use has on rodent and predator activity using motion triggered cameras - V. Rodriguez (2021)
The recreational trails in Gunnison County, Colorado near the Rocky Mountain Biological Laboratory (RMBL) are a valuable resource for the community. RMBL is a prominent field station surrounded by a largely intact ecosystem whose diverse native plants and animals are key to its scientific research and education programs. Human recreation near these areas generates touristic income for the surrounding cities. However, human recreation can lead to behavioral changes in wild animals. Knowing whether the current regulations being implemented on the trails are sufficient to protect the wildlife is imperative. Utilizing methods from RMBL studies conducted in 2019 and 2020, we studied the effects of human use of recreational trails on small mammals and predators. This three-part study used motion triggered cameras to (1) compare the effectiveness of the non-invasive bucket camera traps with live rodent trapping, (2) measure the impact that human activity on trails has on rodents, and (3) measure the impact that human activity on trails has on predators. We found that bucket traps and live-trapping both capture the same nocturnal species, but bucket traps also capture diurnal species. We determined that human recreation (hiking, biking, dogs) had no significant negative impact on rodents (either nocturnal or diurnal) or on the number of predators. There was a marginally significant increase of predators at Deer Creek Trail with human recreation, but no relationship between predator numbers and rodent numbers. We conclude that recreation in the vicinity of RMBL is not having a detectable negative effect on wildlife species diversity or activity.

Chemical Variation among Castes, Female Life Stages and Populations of the Facultative Eusocial Sweat Bee Halictus rubicundus (Hymenoptera: Halictidae) (Journal of Chemical Ecology, 2021)
In eusocial insects, chemical communication is crucial for mediating many aspects of social activities, especially the regulation of reproduction. Though queen signals are known to decrease ovarian activation of workers in highly eusocial species, little is known about their evolution. In contrast, some primitively eusocial species are thought to control worker reproduction through physical aggression by the queen rather than via pheromones, suggesting the evolutionary establishment of chemical signals with more derived sociality. However, studies supporting this hypothesis are largely missing. Socially polymorphic halictid bees, such as Halictus rubicundus, with social and solitary populations in both Europe and North America, offer excellent opportunities to illuminate the evolution of caste-specific signals. Here we compared the chemical profiles of social and solitary populations from both continents and tested whether (i) population or social level affect chemical dissimilarity and whether (ii) caste-specific patterns reflect a conserved queen signal. Our results demonstrate unique odor profiles of European and North American populations, mainly due to different isomers of n-alkenes and macrocyclic lactones; chemical differences may be indicative of phylogeographic drift in odor profiles. We also found common compounds overproduced in queens compared to workers in both populations, indicating a potential conserved queen signal. However, North American populations have a lower caste-specific chemical dissimilarity than European populations which raises the question if both use different mechanisms of regulating reproductive division of labor. Therefore, our study gives new insights into the evolution of eusocial behavior and the role of chemical communication in the inhibition of reproduction.

Nanda-Hamner Curves Show Huge Latitudinal Variation but No Circadian Components in Drosophila Montana Photoperiodism - P. Lankinen; C. Kastally; A. Hoikkala (Journal of Biological Rhythms, 2021)

Firmicutes and Bacteroidetes explain mass gain variation in an obligate hibernator (bioRxiv, 2021)
Abstract Body condition is an important life history challenge that directly impacts individual fitness and is particularly important for hibernating animals, whose maintenance of adequate body fat and mass is essential for survival. It is well documented that symbiotic microorganisms play a vital role in animal physiology and behaviour. Recent work demonstrates that gut microbes are associated with fat accumulation and obesity; Firmicutes is consistently associated with obesity while Bacteroidetes is associated with leanness both in humans and other animals. The focus of most microbiome studies has been on human health or involved lab reared animals used as a model system. However, these microbes likely are important for individual fitness in wild populations and provide potential mechanistic insights into the adaptability and survival of wildlife. Here we test whether symbiotic microorganisms within the phyla of Firmicutes and Bacteroidetes are associated with summer mass gain in an exceptionally well-studied wild population of yellow-bellied marmots ( Marmota flaviventer ) by quantifying microbial abundance over five years of fecal samples (2015 – 2019) collected during their summer active season. Results show that marmots with higher mass gain rates have a greater abundance of Firmicutes . In contrast, higher abundance of Bacteroidetes was associated with lower mass gain rates, but only for marmots living in harsher environments. Similar patterns were found at the family level where Ruminococcaceae , a member of Firmicutes , was associated with higher mass gain rates, and Muribaculaceae , a member of Bacteroidetes , was associated with lower mass gain rates, and similarly in harsher environments. Although correlative, these results highlight the importance of symbiotic gut microbiota to mass gain in the wild, a trait associated with survival and fitness in many taxonomic groups.

Green Light for Adaptive Policies on the Colorado River - Jacob A. Fleck; Anne J. Castle (Water, 2021)
The Colorado River is a critical source of water supply for 40 million people in nine states spanning two nations in western North America. Overallocated in the 20th century, its problems have been compounded by climate change in the 21st century. We review the basin’s hydrologic and water management history in order to identify opportunities for adaptive governance to respond to the challenge of reduced system flows and distill the ingredients of past successes. While significant advances have been made in the first two decades of the 21st century, these past actions have not been sufficient to halt the declines in the basin’s reservoirs. We find that the mix of federal, state, and local responsibility creates challenges for adaptation but that progress can be made through a combination of detailed policy option development followed by quick action at hydrologically driven moments of opportunity. The role of directives and deadlines from federal authorities in facilitating difficult compromises is noted. The current state of dramatically decreased overall flows has opened a window of opportunity for the adoption of water management actions that move the river system toward sustainability. Specific measures, based on the existing institutional framework and on policy proposals that have circulated within the Colorado River community, are suggested.

Meanders as a scaling motif for understanding of floodplain soil microbiome and biogeochemical potential at the watershed scale - S. Diamond; M. R. Olm; A. D. Thomas; R. Meéheust; A. Sharrar; S. Lei; P. B. M. Carnevali; A. Lavy; A. Crits-Christoph; Jillian F. Banfield; Michelle Newcomer; Nicholas J. Bouskill; et al. (Microbiome, 2021)
Abstract Biogeochemical exports of C, N, S and H 2 from watersheds are modulated by the activity of microorganisms that function over micron scales. This disparity of scales presents a substantial challenge for development of predictive models describing watershed function. Here, we tested the hypothesis that meander-bound regions exhibit patterns of microbial metabolic potential that are broadly predictive of biogeochemical processes in floodplain soils along a river corridor. We intensively sampled floodplain soils located in the upper, middle, and lower reaches of the East River in Colorado and reconstructed 248 draft quality genomes representative at a sub-species level. Approximately one third of the representative genomes were detected across all three locations with similar levels of abundance, and despite the very high microbial diversity and complexity of the soils, ~15% of species were detected in two consecutive years. A core floodplain microbiome was enriched in bacterial capacities for aerobic respiration, aerobic CO oxidation, and thiosulfate oxidation with the formation of elemental sulfur. We did not detect systematic patterns of gene abundance based on sampling position relative to the river. However, at the watershed scale meander-bound floodplains appear to serve as scaling motifs that predict aggregate capacities for biogeochemical transformations in floodplain soils. Given this, we conducted a transcriptomic analysis of the middle site. Overall, the most highly transcribed genes were amoCAB and nxrAB (for nitrification) followed by genes involved in methanol and formate oxidation, and nitrogen and CO 2 fixation. Low soil organic carbon correlated with high activity of genes involved in methanol, formate, sulfide, hydrogen, and ammonia oxidation, nitrite oxidoreduction, and nitrate and nitrite reduction. Thus, widely represented genetic capacities did not predict in situ activity at one time point, but rather they define a reservoir of biogeochemical potential available as conditions change.

How worthwhile are pollination networks? - James D. Thomson (Journal of Pollination Ecology, 2021)

The Mountaineer Site: A Folsom Winter Camp in the Rockies - David J. Meltzer; Mark Stiger; Brian N. Andrews (University Press of Colorado eBooks, 2021)
A decade's worth of archaeological research conducted at Mountaineer, a Paleoindian campsite in Colorado's Upper Gunnison Basin. Extensively excavated, long-term Folsom occupations with evidence of built structures. The site provides a record of stone tool manufacture and use offering insight into adaptive strategies from a region in a waning Ice Age.--Provided by publisher.

Porewater Lead Concentrations Limited by Particulate Organic Matter Coupled With Ephemeral Iron(III) and Sulfide Phases during Redox Cycles Within Contaminated Floodplain Soils - Christian Dewey; John R. Bargar; Scott Fendorf (Environmental Science & Technology, 2021)
Lead contamination in soils and sediments is a major threat to water quality. In surface and near-surface environments, Pb is not redox active; however, common Pb hosts, including Fe(III)-(hydr)oxides and sulfides, dissolve and precipitate as redox conditions change. Dissolution of Pb hosts may release Pb to porewater, leading to spikes in dissolved Pb concentrations and potential transport into surface or groundwater. Here, we examine the impacts of hydrologically coupled redox transitions on Pb partitioning in contaminated floodplain soils. We find that the affinity of Pb for particulate organic matter (POM), inclusive of mineral-associated organic matter, ensures that across redox transitions Pb is retained in the solid phase, despite host-phase (Fe(III)-(hydr)oxide and sulfide) dissolution. As seasonal hydrologic dynamics shift porewater redox conditions, Pb-bearing Fe(III)-(hydr)oxides (Pb-HFO) and sulfides (PbS) are dissolved and (re)precipitated. However, despite these shifts in redox conditions and associated host-phase transformations, Pb retention on POM, coupled with the formation of PbS and Pb-HFO, maintains dissolved Pb concentrations below 17 μg L-1. Importantly, the predominance of Pb adsorbed on POM alongside low dissolved Pb concentrations indicates that Pb released from HFO and PbS is retained by POM. Thus, despite host-phase dissolution during redox transitions, partitioning of Pb to the aqueous phase is minimal and, therefore, transport of dissolved Pb is unlikely.