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Eric M Gese

Publications and source records attributed to Eric M Gese.

3 recordsLinked to original sources

Kit foxes demonstrate adaptive compromise characteristics under intraguild predation pressure by coyotes in the Great Basin desert

Coyotes ( Canis latrans ) are believed to contribute to declining kit fox ( Vulpes macrotis ) numbers in the Great Basin desert through intraguild predation. Intraguild prey have been shown to exhibit adaptive compromise, whereby an animal increases selection for risky, but food-rich areas during times of food stress (i.e. winter). We evaluated the habitat selection of kit foxes in the Great Basin desert to elucidate if they demonstrated adaptive compromise as a method of coexisting with coyotes. We created 2nd order resource selection functions to analyze kit fox habitat selection associated with coyote relative probability of use (RPU), prey abundance, and type of soil substrate. In the summer, we found that kit fox selection for areas of relatively more abundant prey was not significant, and there was a small positive selection for coyote RPU. In the winter, we found a positive relationship between kit fox selection and prey abundance as well as a stronger selection for coyote RPU. These findings do follow the pattern of adaptive compromise. We also found kit foxes selected for silty and sandy soils, which are conducive to den construction, as they use dens seasonally for breeding but also year-round for multiple uses, including refugia from predators and extreme heat. Soil substrate appeared to be an important factor impacting kit fox habitat selection.

Utah

Survey and monitoring methods for furbearers

There is a continuing need to assess the state (distribution and abundance) of furbearer populations throughout North America for state and provincial agencies to properly manage furbearers. With an expanding human population and continued changes in land-use practices, habitat loss and fragmentation, declines in natural prey, increases in disease transmission from domestic species, and increased competition with other species, many wildlife agencies have placed the management and conservation of some furbearer species as a top priority. Paramount to making informed decisions regarding management of furbearer populations is accurate information on their current distribution and population status.

Book chapter

Use of subsistence-harvested whale carcasses by polar bears in the southern Beaufort Sea

The availability of a food subsidy has the potential to influence the condition, behavior, fitness, and population dynamics of a species. Since the early 2000s, monitoring efforts along the coast of northern Alaska indicated a higher proportion of polar bears (Ursus maritimus) of the southern Beaufort Sea (SB) subpopulation come onshore and feed at subsistence-harvested bowhead whale (Balaena mysticetus) carcasses during the fall and early winter seasons. This increase in onshore usage by polar bears is a consequence of decreasing sea ice coverage. Concurrently, Indigenous communities annually hunt bowhead whale and deposit the unused remains at localized “bone piles” creating the potential for human-bear interactions. Our objective was to determine the annual number of polar bears feeding at the bone pile near Kaktovik, Alaska. Using a hair snag surrounding the bone pile, we collected hair samples to identify individual bears via microsatellite genotypes during 2011-2014. We used capture-mark-recapture data in the POPAN open-population model to estimate the number of bears visiting the bone pile. We estimated that 146 (SE = 21) bears (sexes combined) used the bone pile in 2012, which represents approximately 16% of the SB polar bear subpopulation. Our results indicated that numerous SB polar bears, males and females, visited the bone pile within a given year. Thus, it will be important to monitor the number of bears using the bone pile and subsequent human-bear interactions and conflicts along the northern coast of Alaska. This is particularly important if polar sea ice continues to recede, which will likely result in increasing numbers of polar bears using the bone pile as a food subsidy.

Alaska