Chronic wasting disease (CWD) is a fatal transmissible spongiform encephalopathy affecting white-tailed deer (Odocoileus virginianus), mule deer (Odocoileus hemionus), Rocky Mountain elk (Cervus elaphus nelsoni), and moose (Alces alces shirasi) in North America. In southeastern Wyoming average annual CWD prevalence in mule deer exceeds 20% and appears to contribute to regional population declines. We determined the effect of CWD on mule deer demography using age-specific, female-only, CWD transition matrix models to estimate the population growth rate (λ). Mule deer were captured from 2010–2014 in southern Converse County Wyoming, USA. Captured adult (≥ 1.5 years old) deer were tested ante-mortem for CWD using tonsil biopsies and monitored using radio telemetry. Mean annual survival rates of CWD-negative and CWD-positive deer were 0.76 and 0.32, respectively. Pregnancy and fawn recruitment were not observed to be influenced by CWD. We estimated λ = 0.79, indicating an annual population decline of 21% under current CWD prevalence levels. A model derived from the demography of only CWD-negative individuals yielded; λ = 1.00, indicating a stable population if CWD were absent. These findings support CWD as a significant contributor to mule deer population decline. Chronic wasting disease is difficult or impossible to eradicate with current tools, given significant environmental contamination, and at present our best recommendation for control of this disease is to minimize spread to new areas and naïve cervid populations.

Wildfires are increasing in size, frequency and severity due to climate change and fire suppression, but the direct and indirect effects on wildlife remain largely unresolved. Fire removes forest canopy, which can improve forage for ungulates but also reduce snow interception, leading to a deeper snowpack and potentially increased vulnerability to predation in winter. If ungulates exhibit predator‐mediated foraging, burns should generally be selected for in summer to access high‐quality forage and avoided in winter to reduce predation risk in deep snow. Fires also typically increase the amount of deadfall and initiate the growth of dense understory vegetation, creating obstacles that may confer a hunting advantage to stalking predators and a disadvantage to coursing predators. To minimize risk, ungulates may therefore avoid burns when and where stalking predators are most active, and use burns when and where coursing predators are most active. We used telemetry data from GPS‐collared mule deer (Odocoileus hemionus), cougars (Puma concolor) and wolves (Canis lupus) to develop step selection functions to examine how mule deer navigated species‐specific predation risk across a landscape in northern Washington, USA, that has experienced substantial wildfire activity during the past several decades. We considered a diverse array of wildfire impacts, accounting for both the severity of the fire and time since the burn (1–35 years) in our analyses. We observed support for the predator mediating foraging hypothesis: mule deer generally selected for burned areas in summer and avoided burns in winter. In addition, deer increased use of burned areas when and where wolf activity was high and avoided burns when and where cougar use was high in winter, suggesting the hunting mode of resident predators mediated the seasonal response of deer to burns. Deer were not more likely to die by predation in burned than in unburned areas, indicating that they adequately manage fire‐induced changes to predation risk. As fire activity increases with climate change, our findings indicate the impact on ungulates will depend on trade‐offs between enhanced summer forage and functionally reduced winter range, mediated by characteristics of the predator community.

Estimating habitat and spatial associations for wildlife is common across ecological studies and it is well known that individual traits can drive population dynamics and vice versa. Thus, it is commonly assumed that individual‐ and population‐level data should represent the same underlying processes, but few studies have directly compared contemporaneous data representing these different perspectives. We evaluated the circumstances under which data collected from Lagrangian (individual‐level) and Eulerian (population‐level) perspectives could yield comparable inference to understand how scalable information is from the individual to the population. We used Global Positioning System (GPS) collar (Lagrangian) and camera trap (Eulerian) data for seven species collected simultaneously in eastern Washington (2018–2020) to compare inferences made from different survey perspectives. We fit the respective data streams to resource selection functions (RSFs) and occupancy models and compared estimated habitat‐ and space‐use patterns for each species. Although previous studies have considered whether individual‐ and population‐level data generated comparable information, ours is the first to make this comparison for multiple species simultaneously and to specifically ask whether inferences from the two perspectives differed depending on the focal species. We found general agreement between the predicted spatial distributions for most paired analyses, although specific habitat relationships differed. We hypothesize the discrepancies arose due to differences in statistical power associated with camera and GPS‐collar sampling, as well as spatial mismatches in the data. Our research suggests data collected from individual‐based sampling methods can capture coarse population‐wide patterns for a diversity of species, but results differ when interpreting specific wildlife‐habitat relationships.

Quantification of basic demographic parameters such as survival rates and cause-specific mortality is important for effective species management. We conducted a 4-year study (during May 2005-June 2009) of elk Cervus canadensis calf survival and cause-specific mortality in Pennsylvania, USA. We captured and radio-collared 93 elk calves 7 days old and monitored them weekly to detect mortality and cause of death. Of the 93 radio-collared elk calves, 15 (16%) died during our study. Despite high black bear Ursus americanus and coyote Canis latrans densities, none of the mortalities were the result of predation. Causes of death included poaching (N ¼ 3), legal harvest (N ¼ 2), road kill (N ¼ 2), pneumonia (N ¼ 1) and rumen acidosis (N ¼ 1). We were unable to determine the cause of mortality for six of the elk calves; however, predation was eliminated as a possible source of mortality in all unknown cases. Survival probabilities were similar between sexes and among years. Summer survival (birth-31 October) was 0.92 (SE ¼ 0.03, N ¼ 93) and winter survival (1 November-1 April) was 0.90 (SE ¼ 0.04, N ¼ 79). Annual estimated elk calf survival was 0.82 (SE ¼ 0.04, N ¼ 93). Our findings suggest that Pennsylvania elk calves have a. 80% chance of survival to one-year of age, despite high densities of predators known to influence elk calf survival elsewhere. The high calf survival rates that we observed indicate the availability of high quality habitat leading to excellent physical condition of elk.

Across eastern North America, Rocky Mountain elk Cervus canadensis nelsoni have been reintroduced to 11 states and provinces that were previously occupied by the extinct eastern elk C. canadensis canadensis. Outside of Kentucky, these elk reintroductions have resulted in small populations, typically numbering fewer than 1,000 elk per state. Limited information is available about the demographics and habitat selection within these small eastern populations. The availability of high-quality habitat during the first weeks of life is important for promoting annual recruitment and the identification of these characteristics should aid in management efforts. We characterized habitat at two spatial scales surrounding the bedding sites of 83 elk calves ( 7 d old) in the Pennsylvania Elk Management Area during the annual calving seasons of [2005][2006][2007][2008]. A concurrent study found that calves in this area experienced high survival (92%) during the first 4 mo of life, despite occupying an area with high predator densities. At a local scale, bedding sites used by calves were closer to ecotones, had less leaf litter, and had greater density of vegetation below 1 m compared to random sites (n ¼ 82). At a landscape scale, calf habitat surrounding bedding sites had greater density of edges between forest and open vegetation and less coniferous forest compared to random areas. The selected habitats appear to balance the high energetic needs of lactating females at the landscape scale and the need for cover to conceal calves and reduce predation risk at a local scale. Conclusions drawn from our models suggest future habitat management include enhancements of transitional vegetation along ecotones between forest and herbaceous openings that address the needs of both lactating females and recently born calves. We recommend that managers periodically evaluate the availability of calf habitat and calf survival rates. These monitoring activities will provide insight necessary to adaptively manage elk and the habitats driving their population growth to maintain their viability in the central Appalachian Mountains.