This is a map of temporal variability in spring accumulated freezing potential (freezing degree days, FDD) for the Upper Gunnison domain, derived from daily minimum temperature maps interpolated from weather station and microclimate sensor data. The original daily maps are also available. Freezing d

This is a map of spring accumulated freezing potential (freezing degree days, FDD) for the Upper Gunnison domain, derived from daily minimum temperature maps interpolated from weather station and microclimate sensor data. The original daily maps are also available. Freezing degree-days were accumula

W. B. Watt, C. Kremen, P. Carter, Testing the `Mimicry' Explanation for the Colias `alba' Polymorphism: Patterns of Co-Occurrence of Colias and Pierine Butterflies, Functional Ecology, Vol. 3, No. 2 (1989), pp. 193-199

Restricted gene flow and localized selection should establish a correlation between physical proximity and genetic similarity in many plant populations. Given this situation, fitness may decline in crosses between nearby plants (inbreeding depression), and in crosses between more widely separated pl

I implanted radio transmitters in 183 yellow-bellied marmots (Marmota flaviventris); transmitters were replaced -<6 times in 73 animals, for 300 surgeries. Surgical procedures were simple, effective, and largely trouble-free. Survival 30 days later was -98%, and growth rates (21 g/day) were the same

EvolutionVolume 43, Issue 1 p. 220-223 Note and CommentFree Access GERMINATION SCHEDULES OF POLLEN GRAINS: IMPLICATIONS FOR POLLEN SELECTION James D. Thomson, James D. Thomson Department of Ecology and Evolution, State University of New York at Stony Brook, Stony Brook, NY, 11794 Rocky Mountain Biol

This study is the first to document the use of hydrodynamic cues by stream-dwelling predators for discrimination of prey from nonprey and provides a mechanism to explain selective predation by stoneflies on Baetis in nature.

Behavior of Baetis bicaudatus (Ephemeroptera; Baetidae) was video taped in a western Colorado, USA stream to identify the specific stimuli eliciting noncontact responses to predatory stoneflies (Kogotus modestus; Plecoptera; Perlodidae). In situ behavioral and feeding trial experiments were also con

Energy intake, daily energy expenditure (DEE), and energy available for production were determined for yellow-bellied marmots (Marmota flaviventris) at three study sites in the Elk Mountains of southwestern Colorado. Energy intake, estimated from tritiated-water turnover rates and the water and ener

C. Ley, W. B. Watt, Testing the `Mimicry' Explanation for the Colias `alba' Polymorphism: Palatability of Colias and Other Butterflies to Wild Bird Predators, Functional Ecology, Vol. 3, No. 2 (1989), pp. 183-192

There is growing evidence of nonrandom reproductive success in plants. The potential evolutionary effect of these patterns depends on the extent to which they reflect nonrandom transmission of genes between generations. A recent tendency has been to examine these patterns in the context of sexual se

Abstract: To investigate possible biological effects of acidic deposition in the western United States, we performed population censuses and dose‐response experiments at a subalpine watershed in the Rocky Mountains of Colorado, An adult tiger salamander (Ambystoma tigrinum nebulosum) population decl

Blood samples were obtained in the field by femoral vein puncture in bushy-tailed woodrats (Neotoma cinerea) and yellow-bellied marmots (Marmota flaviventris) that had been injected intramuscularly with ketamine hydrochloride. Dosages ranged from 50 mg/kg for marmots to 30 to 110 mg/kg for woodrats.

Yellow-bellied marmots (Marmota flaviventris) eat a wide variety of grasses, forbs, and seeds, but do not feed on all items in proportion to their abundance in the environment. In this study, relationships between the marmot diet and estimated protein, water, caloric value, relative biomass, and tox