Growth and adult survival rates were estimated for the endangered Colorado squawfish Ptychocheilus lucius inhabiting the upper Colorado River by using data from fish captured during 1990–1995. Mean annual growth rates of fish aged 3–6 years ranged from 32.2 (age 6) to 82.0 (age 3) mm/year. Growth ra

Abstract Water is a critical resource that causes significant challenges to inhabitants of the western United States. These challenges are likely to intensify as the result of expanding population and climate-related changes that act to reduce runoff in areas of complex terrain. To better understand

Nectar robbers are often assumed to be plant antagonists; however, empirical data show that the impacts of these animals range from negative to positive depending on the system and ecological conditions. We experimentally evaluated the combined effects of nectar robbing and ant visitation on three i

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. Al

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

Individuals of many species produce distinctive vocalizations that may relay potential information about the signaller. The alarm calls of some species have been reported to be individually specific, and this distinctiveness may allow individuals to access the reliability or kinship of callers. Whil

It is concluded that, even for species with qualitatively similar life histories, differences in physiological, behavioral and environmental tradeoffs or constraints may strongly influence optimal allocation schedules and produce variation in mortality patterns and life expectancy.

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

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.

Research on floral volatiles has grown substantially in the last 20 years, which has generated insights into their diversity and prevalence. These studies have paved the way for new research that explores the evolutionary origins and ecological consequences of different types of variation in floral

The dynamics of soil organic carbon (SOC) storage and turnover are a critical component of the global carbon cycle. Mechanistic models seeking to represent these complex dynamics require detailed SOC compositions, which are currently difficult to characterize quantitatively. Here, we address this ch

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

-Field tests quantifying the behavioral responses of ants to the seeds of twenty Rocky Mountain species were conducted in Gunnison County, Colorado. The results indicate that Claytonia lanceolata Pursh, Corydalis aurea Willd., C. caseana A. Gray., Delphinium nelsoni Greene, and Viola nuttallii Pursh

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

-Analysis of contents of 395 coyote (Canis latrans) scats collected for 6 yr at a subalpine locality in Colorado showed that yellow-bellied marmots (Marmota flaviventris) were a regular and frequent prey of coyotes during summer. There was no evidence that marmots were especially vulnerable to preda

It is concluded that bees prefer to visit magenta-coloured flowers with a sparkling surface, which has implications for the idea of ‘pollination syndromes’, whereby certain plants are thought to be adapted to attract particular pollinators.

The results suggest that a mother's life history stage interacts with stress to influence offspring personality, a personality trait, and can have long lasting effects on an individual's docility throughout life.

Abstract Snow is a vital part of water resources, and sublimation may remove 10%–90% of snowfall from the system. To improve our understanding of the physics that govern sublimation rates, as well as how those rates might change with the climate, we deployed an array of four towers with over 100 ins