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James W Cain

The responses of individual species to environmental changes can be manifested at multiple levels that range from individual-level (i.e., behavioral responses) to population-level (i.e., demographic) impacts. Major environmental changes that ultimately result in population level impacts are often first detected as individual-level responses. For example, herbivores respond to limited forage availability during drought periods by increasing the duration of foraging periods and expanding home range areas to compensate for the reduction in forage. However, if the individual-level responses are not sufficient to compensate for reduced forage availability, reduced survival and reproductive rates may result. We studied...
The elk (Cervus canadensis) of the Jemez herd reside primarily in and around the Valles Caldera National Preserve, west of Los Alamos, NM and along the mesa tops to the north and west of the Valles Caldera. The area has experienced two wildfires, the stand replacing Las Conchas Fire and the mixed severity Thompson Ridge fire, within the last decade, burning a total of 180,555 acres. The data used in this report was collected to examine the responses of elk to these wildfires and forest restoration treatments. The Jemez herd is only partially migratory, with residents that consistently remain on the Valles Caldera and individuals that travel to the surrounding lower elevation slopes depending on the year and snowpack...
The mule deer (Odocoileus hemionus) of the Jemez Springs herd winter in the southwestern Jemez Mountains, south and east of the town of Jemez Springs. The area has experienced two severe wildfires, the Las Conchas and Thompson Ridge fires, within the last decade, burning a total of 180,555 acres. The data used in this report was collected to examine the responses of mule deer to these wildfires and forest restoration treatments. The winter range is located among the foothills of the Jemez Mountains, consisting primarily of pinyon-juniper woodlands. Individuals migrated an average of 26.1 miles, either to the western edge of the Jemez Mountains, near Blue Bird Mesa, or to the Valles Caldera. The central migration...
Abstract (from http://www.esajournals.org/doi/abs/10.1890/ES15-00266.1): Climate often drives ungulate population dynamics, and as climates change, some areas may become unsuitable for species persistence. Unraveling the relationships between climate and population dynamics, and projecting them across time, advances ecological understanding that informs and steers sustainable conservation for species. Using pronghorn ( Antilocapra americana) as an ecological model, we used a Bayesian approach to analyze long-term population, precipitation, and temperature data from 18 populations in the southwestern United States. We determined which long-term (12 and 24 months) or short-term (gestation trimester and lactation period)...
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Feral burros (Equus asinus) and horses (E. ferus caballus) inhabiting public land in the western United States are intended to be managed at population levels established to promote a thriving, natural ecological balance. Like many large ungulate populations, management agencies employ aerial surveys to obtain estimates of horse and burro population sizes. Double-observer sightability (MDS) models perform well for estimating feral horse abundances, yet the effectiveness of these models for use in burro populations is less understood and may be different due to the smaller size, stoic behavior, and cryptic pelage of burros. These models help minimize detection bias, yet bias can be further reduced with models that...
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