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Wildfire activity across the western United States has increased in recent decades, with wildfires burning at a higher severity and larger scale. The effect of wildfires on forest structure and wildlife habitat is largely influenced by wildfire severity; however, few studies have evaluated the effects of wildfire severity on resource selection of ungulates, particularly during hunting seasons, when knowledge of resource selection is essential for making informed management decisions. To fill this knowledge gap, we fit resource selection probability functions for female elk (Cervus canadensis) in years 2 and 3 post‐wildfire to evaluate the effects of wildfire severity and other environmental and anthropogenic factors on elk resource selection during 4 autumn periods with varying levels of hunter pressure (prehunt, archery‐only, backcountry rifle, and rifle). The probability of female elk selecting low‐severity burned forests during the prehunt, archery‐only, backcountry rifle, and rifle periods was 0.99 (95% credible interval [CrI] = 0.98–1.00), 0.99 (CrI = 0.97–1.00), 0.99 (CrI = 0.99–1.00), and 0.0010 (CrI = 0.00067–0.0015]), respectively, and did not strongly differ from the probability of selecting high‐severity burned forests. During the prehunt period, elk also selected areas with greater forage quality and areas farther from open roads. Elk selected similar resources during the archery period, and selected areas with higher hunter pressure. Elk started leaving hunting districts that had higher snowpack (i.e., snow water equivalent; β = −0.84, CrI = −0.96–−0.72) and allowed rifle hunting (β = −5.39, CrI = −5.80–−4.97) but still selected areas with higher hunter pressure (β = 0.92, CrI = 0.78–1.07) during the backcountry rifle period. During the rifle period, elk continued avoiding areas with high snowpack (β = −3.96, CrI = −4.22–−3.71) and started selecting areas with lower hunter pressure (β = −1.71, CrI = −1.79–−1.64) and lower canopy cover. Overall, wildfire affected elk distributions in early autumn 2 and 3 years after fire in our study area, with limited differences in resource selection between wildfire severity categories. By late autumn, hunter pressure and snowpack were the primary factors influencing elk distribution, and wildfire had little influence on selection. When estimating wildfire effects on elk movements during autumn and establishing appropriate hunting regulations, managers should consider the hunting season, hunter pressure, timing and amount of snowpack, location of traditional winter range, and the seasonal elk range burned, as all these factors may contribute to how elk use the landscape in autumn. [ABSTRACT FROM AUTHOR]

Brucellosis is a disease caused by the bacterium Brucella abortus that infects elk (Cervus canadensis) and cattle (Bos taurus). There is the potential for transmission from wildlife to livestock through contact with infected material shed during abortions or live births. To understand the impact of exposure on pregnancy rates we captured 30–100 elk per year from 2011 through 2020, testing their blood for serologic exposure to B. abortus. Predicted pregnancy rates for seropositive animals were 9.6% lower in prime-age (2.5–15.5 yr; 85%, 95% confidence interval [CI]: 74–91%) and 37.7% lower in old (>15.5 yr; 43%, 95% CI: 19–71%) elk as compared with seronegative animals. To understand the risk of seropositive elk shedding B. abortus bacteria and the effects of exposure on elk reproductive performance, we conducted a 5-yr longitudinal study monitoring 30 seropositive elk. We estimated the annual probability of a seropositive elk having an abortion as 0.06 (95% CI: 0.02–0.15). We detected B. abortus at three abortions and two live births, using a combination of culture and PCR testing. The predicted probability of a pregnant seropositive elk shedding B. abortus during an abortion or live birth was 0.08 (95% CI: 0.04–0.19). To understand what proportion of seropositive elk harbored live B. abortus bacteria in their tissues, we euthanized seropositive elk at the end of 5 yr of monitoring and sampled tissues for B. abortus. Assuming perfect detection, the predicted probability of a seropositive elk having B. abortus in at least one tissue was 0.18 (95% CI: 0.06–0.43). The transmission risk seropositive elk pose is mitigated by decreased pregnancy rates, low probability of abortion events, low probability of shedding at live birth events, and reasonably low probability of B. abortus in tissues. [ABSTRACT FROM AUTHOR]

Changes in ungulate distribution can alter competitive interactions, plant communities, risks of zoonotic disease transmission, and availability of animals for harvest. We used annual aerial survey data for northern Yellowstone elk in Montana and Wyoming, USA to evaluate factors influencing distribution and group sizes during 1987- 2009 in four sectors of elk winter range corresponding to river watersheds with different minimum elevations and snowpacks. Our best logistic regression model suggested the proportion of elk occupying the upper elevation sector decreased following wolf restoration and increased snowpack. The proportion of elk occupying the lower elevation sector increased following wolf restoration and as snowpack increased at higher elevations. Linear regression suggested group sizes increased in the lower elevation sector after wolves were restored. Concurrent demographic and movement studies suggest these changes resulted primarily from the attrition of elk from high snow areas in Yellowstone National Park due to predation, and increased survival and recruitment of elk in lower snow areas outside the Park in Montana following a substantial reduction in hunter harvest. Fitness trade-offs between foraging conditions and the risks of predation (or harvest) as constrained by snow vary considerably among elk populations in the Yellowstone ecosystem., INTRODUCTION Understanding elk (Cervus elaphus) responses to changes in climate, land use, and predation risk is necessary because such responses may have significant ecological consequences, including changes in prey distributions, [...]