2,570 results — type: Journal Article

Article

Three-Dimensional Surface Downwelling Longwave Radiation Clear-Sky Effects in the Upper Colorado River Basin

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

2022Geophysical Research LettersDOI: 10.1029/2021GL094605Cited 17 times
Article

Harvest rates and escape speeds in two coexisting species of montane ground squirrels

I measured harvest rates and maximum running-escape speeds of two species of ground-dwelling squirrels, the least chipmunk (Tamias minimus) and the golden-mantled ground squirrel (Spermophilus lateralis). Using seed trays in which foragers experienced diminishing returns, I found that S. lateralis h

1995Journal of MammalogyDOI: 10.2307/1382327Cited 17 times
Article

Plant–pollinator interaction niche broadens in response to severe drought perturbations

The composition of plant–pollinator interactions—i.e., who interacts with whom in diverse communities—is highly dynamic, and we have a very limited understanding of how interaction identities change in response to perturbations in nature. One prediction from niche and diet theory is that resource ni

2021OecologiaDOI: 10.1007/s00442-021-05036-0Cited 17 times
Article

Distance to a road is associated with reproductive success and physiological stress response in a migratory landbird

We investigated the impacts of an unpaved road on the distribution, reproduction, and stress physiology of Mountain White-crowned Sparrows (Zonotrichia leucophrys oriantha) in a high-elevation subalpine ecosystem. We found and monitored 152 sparrow nests over 3 years and captured 123 sparrows over 2

2013The Wilson Journal of OrnithologyDOI: 10.1676/11-201.1Cited 17 times
Article

Hummingbird foraging at experimental patches of flowers: evidence for weak risk-aversion

Hummingbirds foraging for nectar in mountains of the western USA encounter spatially-variable rewards under energetically-demanding environmental conditions. Previous workers have found that hummingbirds respond quickly to the average quantity and quality of reward; in addition, one might expect a r

1998Journal of Avian BiologyDOI: 10.2307/3677113Cited 16 times
Article

Inter- and intraspecific variation in the acoustic habitats of three marmot species

Closely related species often have remarkably different vocalizations. Some of the variation in acoustic structure may result from species adapting their calls to maximize transmission through their acoustic environ- ments. We document the relative magnitude of inter- and intraspecific variation in

1997EthologyDOI: 10.1111/j.1439-0310.1997.tb00022.xCited 16 times
Article

Delayed population explosion of an introduced butterfly

Summary The causes of lagged population and geographical range expansions after species introductions are poorly understood, and there are relatively few detailed case studies. We document the 29‐year history of population dynamics and structure for a population of Euphydryas gillettii Barnes that w

2006Journal of Animal EcologyDOI: 10.1111/j.1365-2656.2006.01067.xCited 16 times
Article

Quantifying Whitewater Recreation Opportunities in Cataract Canyon of the Colorado River, Utah: Aggregating Acceptable Flows and Hydrologic Data to Identify Boatable Days

AbstractThe structural norm approach was combined with the Potential for Conflict Index to define recreation streamflow needs for the Colorado River in Utah and Colorado. An online survey was completed by 128 commercial and non‐commercial boaters, who evaluated a range of flows for whitewater boatin

2017River Research and ApplicationsDOI: 10.1002/rra.3049Cited 16 times
Article

Variations in bedrock and vegetation cover modulate subsurface water flow dynamics of a mountainous hillslope

Abstract Predicting the hydrological response of watersheds to climate disturbances requires a detailed understanding of the processes connecting hillslopes and streams. Using a network of soil moisture and temperature sensors, electrical resistivity tomography monitoring, and a weather station we a

2024Water Resources ResearchDOI: 10.1029/2023WR036137Cited 16 times
Article

APPLICATIONS OF A GIS FOR MODELING THE SENSITIVITY OF WATER RESOURCES TO ALTERATIONS IN CLIMATE IN THE GUNNISON RIVER BASIN, COLORADO<sup>1</sup>

ABSTRACT: The Gunnison River drains a mountainous basin in western Colorado, and is a large contributor of water to the Colorado River. As part of a study to assess water resource sensitivity to alterations in climate in the Gunnison River basin, climatic and hydrologic processes are being modeled.

1993JAWRA Journal of the American Water Resources AssociationDOI: 10.1111/j.1752-1688.1993.tb03265.xCited 16 times
Article

The shape of a species\\\' spatial abundance distribution

ABSTRACTAim The shape of a species' spatial abundance distribution may change with spatial scale. We predict that the shape will typically change from strictly downward‐sloping (falling) to humped (rising then falling) as the spatial scale increases. The prediction, motivated in part by central limi

2012Global Ecology and BiogeographyDOI: 10.1111/j.1466-8238.2011.00755.xCited 16 times
Article

Reproduction in Polymonium: a five year study of seed production and implications for competition for pollinator service

Conditions necessary for intraspecific competition for pollinator service, but not intraspecific competition itself, have previously been reported for a population of Polemonium foliossisimum Gray. As in most recent work of this sort, this conclusion was based, in part, on seed set differentials amo

1984OikosDOI: 10.2307/3544797Cited 16 times
Article

Adaptation of heart and lung weight to high altitude in the robin

Journal Article Adaptation of Heart and Lung Weight to High Altitude in the Robin Get access William A. Dunson William A. Dunson Department of Biology, Yale University, New Haven, Connecticut Present address: Department of Zoology, University of Michigan, Ann Arbor, Michigan Search for other works b

1965CondorDOI: 10.2307/1365399Cited 16 times
Article

Resting and field metabolic rates of adult male yellow-bellied marmots, Marmota flaviventris

Total RMR and field metabolic rate of wild-caught males were estimated from oxygen consumption and the doubly-labeled water method and neither total RMR nor specific FMR were significantly related to time.

1994Comparative Biochemistry and PhysiologyDOI: 10.1016/0300-9629(94)90343-3Cited 16 times
Article

Flower behavior in Linum lewisii: some ecological and physiological factors in opening and abscission of petals

Fredrick T. Addicott, Flower Behavior in Linum lewisii: Some Ecological and Physiological Factors in Opening and Abscission of Petals, The American Midland Naturalist, Vol. 97, No. 2 (Apr., 1977), pp. 321-332

1977American Midland NaturalistDOI: 10.2307/2425097Cited 16 times
Article

The amino acids of extrafloral nectar from Helianthella quinquenervis (Asteraceae)

The extrafloral nectar from involucral bracts of Helianthella quinquenervis has more nonprotein (5) and total (24) amino acids than have been reported for any other extrafloral nectar. Seven to twelve additional unknowns, probably nonprotein amino acids, were also found. The concentrations of amino

1980American Journal of BotanyDOI: 10.1002/j.1537-2197.1980.tb07772.xCited 16 times
Article

Climate forcing controls on carbon terrestrial fluxes during shale weathering

Climate influences near-surface biogeochemical processes and thereby determines the partitioning of carbon dioxide (CO 2 ) in shale, and yet the controls on carbon (C) weathering fluxes remain poorly constrained. Using a dataset that characterizes biogeochemical responses to climate forcing in shale

2024Proceedings of the National Academy of SciencesDOI: 10.1073/pnas.2400230121Cited 16 times
Article

Discriminating Quartzite Sources Petrographically in the Upper Gunnison Basin, Colorado: Implications for Paleoamerican Lithic-Procurement Studies

Archaeologists lack a protocol for systematically attributing quartzite artifacts to particular geologic sources of the material. This paper, in an effort to begin to remedy that situation, reports the preliminary results of a petrographic study of quartzite samples from the Upper Gunnison Basin (UG

2016PaleoAmericaDOI: 10.1080/20555563.2015.1137684Cited 16 times
Article

From Grain to Floodplain: Evaluating heterogeneity of floodplain hydrostatigraphy using sedimentology, geophysics, and remote sensing.

AbstractStratigraphy is a fundamental component of floodplain heterogeneity and hydraulic conductivity and connectivity of alluvial aquifers, which affect hydrologic processes such as groundwater flow and hyporheic exchange. Watershed‐scale hydrological models commonly simplify the sedimentology and

2019Earth Surface Processes and LandformsDOI: 10.1002/esp.4613Cited 16 times
Article

Mixed support for state maintaining risky personality traits in yellow-bellied marmots

In a variety of taxa, individuals behave in consistently different ways. However, there are relatively few studies that empirically test the potential mechanisms underlying the causes and maintenance of these personality differences. Several hypotheses for the causes and maintenance of risky persona

2019Animal BehaviourDOI: 10.1016/j.anbehav.2019.02.008Cited 16 times