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Intracranial abscessation is a cause of natural mortality among free-ranging white-tailed deer (Odocoileus virginianus) across portions of the United States and Canada. Intracranial abscesses caused by Arcanobacterium pyogenes disproportionately affect adult male white-tailed deer. From 2003-08, we evaluated the occurrence of intracranial abscessation among adult (> or = 2.5 yr) radiocollared male white-tailed deer (n=33) at a large private property in Kent County, Maryland, USA. We documented mortality and necropsied 26 (79%) of the 33 deer. In 2007, we collected swabs from the antler bases and nasopharyngeal membranes of living male white-tailed deer in Maryland, USA (n=9), and Texas, USA (n=10), and from freshly rubbed (n=7) and unrubbed (n=7) trees in Maryland, USA. Swabs were cultured for the presence or absence of A. pyogenes. In Maryland, USA, nine (35%) of the 26 necropsied radiocollared male deer had intracranial abscesses. Five (56%) of nine Maryland, USA, males, and none (0%) of 10 Texas, USA, males cultured positive for A. pyogenes. No rubbed or unrubbed trees at the Maryland site cultured positive for A. pyogenes. The rate of intracranial abscess among adult male white-tailed deer at the Maryland, USA, site (35%) exceeds reported rates for other regions of the United States (9%).

Successful management of exploited wildlife populations is contingent upon understanding what variables most affect mortality rates (e.g., legal harvest mortality) and adopting regulations that directly address those factors in a manner that accomplishes desired outcomes. We tested biological, ecological, and sociocultural variables related to female white-tailed deer (Odocoileus virginianus) harvest densities in Ohio, USA, during 2007USA, during -2012. At the county level, the proportion of farmland (standardized-b ¼ À0.37, P < 0.001), the proportion of noncrop cover types within farmland (standardized-b ¼ 0.46, P < 0.001), and per capita deer permit sales (hunting pressure; standardized-b ¼ 0.32, P < 0.001) explained 76% of the variance in female white-tailed deer harvest density. Available habitat likely influences harvest density through the direct relationship of deer abundance and forage availability and indirectly through the effect of cover on deer vulnerability and hunter access. The proxy for hunting pressure also was positively related to female deer harvest density, thereby underscoring the important role of hunters in Ohio's white-tailed deer management. Understanding how county-level factors are related to female deer harvest densities is a first step toward basing deer management units and management actions on a solid understanding of landscapeharvest dynamics. Ó

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Decisions concerning the appropriate listing status of species under the U.S. Endangered Species Act (ESA) can be controversial even among conservationists. These decisions may determine whether a species persists in the near term and have long-lasting social and political ramifications. Given the ESA's mandate that such decisions be based on the best available science, it is important to examine what factors contribute to experts' judgments concerning the listing of species. We examined how a variety of factors (such as risk perception, value orientations, and norms) influenced experts' judgments concerning the appropriate listing status of the grizzly bear (Ursus arctos horribilis) population in the Greater Yellowstone Ecosystem. Experts were invited to complete an online survey examining their perceptions of the threats grizzly bears face and their listing recommendation. Although experts' assessments of the threats to this species were strongly correlated with their recommendations for listing status, this relationship did not exist when other cognitive factors were included in the model. Specifically, values related to human use of wildlife and norms (i.e., a respondent's expectation of peers' assessments) were most influential in listing status recommendations. These results suggest that experts' decisions about listing, like all human decisions, are subject to the use of heuristics (i.e., decision shortcuts). An understanding of how heuristics and related biases affect decisions under uncertainty can help inform decision making about threatened and endangered species and may be useful in designing effective processes for protection of imperiled species.