Recent studies in snowmelt-dominated catchments have documented changes in nitrogen (N) retention over time, such as declines in watershed exports of N, though there is a limited understanding of the controlling processes driving these trends. Working in the mountainous headwater East River Colorado

• Premise of the study: Climate change threatens to alter the timing and magnitude of abiotic cues that synchronize mast flowering, such as temperature and precipitation. Climate change may therefore alter the frequency of masting, in turn affecting species in the community that use pulsed resources

Yellow-bellied marmots express considerable individuality as measured by behavior in a maze, mirror-image stimulation (MIS), and social behavior in the field, suggesting that marmot have individual behavioral phenotypes that are expressed in their social interactions with their conspecifics.

In the East Brush Creek area a calcareous siltstone bed contains numerous cylindrical structures normal to the bedding. The bed is 35 feet above the "Shinarump" conglomerate of other workers in the region. The conglomerate is here considered Permian(?) rather than Triassic, because the Shinarump of

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 kno

Abstract Shales contain high levels of organic carbon (OC) and represent a large fraction of the Earth's reduced carbon stocks. While recent evidence suggests that shale‐derived OC may be actively cycled in riverine systems, this process is poorly understood and not currently considered in global C

Phytophagous insects that deposit eggs directly on hosts confront a plant world of variable quality. Some studies to date provide evidence for positive relationships between the site of oviposition and offspring success, as expected if females choose sites of high quality or if they or their offspri

A number of hypotheses are presented to explain why the parasite causes increased predation on its host, including the large size of the parasite affecting the sensory abilities of the host, the larger energetic costs of escape behavior for parasitized individuals, and natural selection from fish pr

The analysis indicated that λ was proportionately more sensitive to survival than recruitment, and the annual fluctuation in litter size, abetted by the breeding probabilities, accounted for most of the temporal variation in λ.

Projections of greenhouse gas concentrations over the twenty-first century generally rely on two optimistic, but questionable, assumptions about the carbon cycle: 1) that elevated atmospheric CO2 concentrations will enhance terrestrial carbon storage and 2) that plant migration will be fast relative

Journal Article Food Supply and Nest Timing of Broad-Tailed Hummingbirds in the Rocky Mountains Get access Nickolas M. Waser Nickolas M. Waser Department of Ecology and Evolutionary Biology, University of Arizona, Tuscan, Arizona 85721 and Rocky Mountain Biological Laboratory, Crested Butte, Colorad

Species' geographic range shifts toward higher latitudes and elevations are among the most frequently reported consequences of climate change. However, the role of species interactions in setting range margins remains poorly understood. We used cage experiments in ponds to test competing hypotheses

The results suggest that elevated baseline FGM levels failed to mediate reproductive suppression in marmots, highlighting the importance of social status, body condition and predator abundance on determining reproductive success in highly seasonal breeders.

Observational and experimental results show the importance of multitrophic species interactions for predicting the effect of climate change on the abundances of herbivores.

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

Estimation of the number of species at spatial scales too large to census directly is a long- standing ecological challenge. A recent comprehensive census of tropical arthropods and trees in Panama provides a unique opportunity to apply an inference procedure for up-scal- ing species richness and th

Background: Trait evolution and plasticity are expected to interactively influence responses to climate change, but rapid changes in and increased variability of temperature may limit evolutionary responses. We use historical specimens to document changes in the size and thermoregulatory traits of a

A key characteristic of host–parasite interactions is the theft of host nutrients by the parasite, yet we lack a general framework for understanding and predicting the interplay of host and parasite nutrition that applies across biological levels of organization. The elemental nutrients (C, N, P, Fe

A fluorescent-dye technique permitted the mating success of male checkerspot butterflies aggregating on a ridge to be compared with that of males on the slope below. Unexpectedly, the males on the ridge had about one-half the mating success of those on the slope. We suggest that formation of this an

Yellow-bellied marmots Marmota flaviventris were live-trapped and marked in the East River Valley of Colorado from 1962 to 1998. For females, static life tables were calculated each year from 1967, when ages were well known, to 1997. Population density was determined, and from life tables calculatio