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Anthropogenic pressure, such as urbanization and habitat loss, can wield many effects on wildlife that radiate through ecosystems. Large carnivores tend to experience these effects more severely than other species, diminishing their viability and altering ecosystem function by suppressing their role as an apex predator. Yet opportunistic carnivores that rely on an omnivorous diet can sometimes take advantage of anthropogenic food and improve their fitness prospects. We quantified the effect of phenotypic and ecological factors on female body mass of the American black bear (Ursus americanus) in New Jersey, USA. Habitat and reliable mast crops in New Jersey keep adult female black bear body mass and reproduction higher than many parts of the United States, and historically, female black bears in the mid‐Atlantic states tend to be larger than in other parts of their range. We used data collected from den surveys (n = 317) in northern New Jersey from 1984 to 2019 to examine the shared roles of climate, anthropogenic pressure (human food subsidies, harvest), habitat composition and configuration, natural food availability (hard mast production), and bear characteristics (age, history of human–black bear conflict) on female black bear body mass using generalized linear mixed models. Adult female body mass was heaviest with increased availability of cultivated crop and within low‐intensity developed land covers, suggesting anthropogenic food subsidies found in these 2 land cover types are contributing to female overall body mass. A history of conflict with humans explained heavier females, and a quadratic effect of age on body mass supported a senescent decline in adult female body mass later in life. Our results suggest that access to specific land cover types (i.e., crops, low‐intensity developments) that provide a diversity of food (e.g., corn, soft and hard mast) and support low human densities, explains female black bear body mass in a fragmented landscape. [ABSTRACT FROM AUTHOR]

ABSTRACT Harvest indices are used by state wildlife management agencies to monitor population trends and set harvest quotas for furbearer species. Although harvest indices may be readily collected from hunters, the reliability of harvest indices for monitoring demography and abundance of the harvested species is rarely examined, particularly amongst large carnivores. The overall objective of this study was to assess whether cougar ( Puma concolor) harvest statistics collected by wildlife managers were correlated with changes in cougar demography, mainly survival rates and abundance. We estimated key demographic parameters for 2 cougar populations in Utah over 17 years during which we monitored 235 radio-collared cougars. We then compared these demographic parameters to harvest statistics provided by the Utah Division of Wildlife Resources over the same time period for the Oquirrh-Stansbury (lightly harvested population) and Monroe (heavily harvested population) harvest management units. In the Oquirrh-Stansbury unit, the percent of harvested cougars >6 years old was positively correlated with annual survival, indicative of a population experiencing several years of high survival resulting in an older age structure. Percent of permits filled and cougar abundance were also significantly correlated, suggesting higher hunting success with increased density. In the Monroe management unit, the annual percent of permits filled was correlated with changes in overall annual survival and male and female annual survival. Of utmost importance, pursuit success (cougars treed/day) increased with the number of cougars on the unit suggesting that pursuit indices may be an informative metric for wildlife managers to determine cougar population trends. Because both management units were subjected to contrasting mortality regimes, results provided by this assessment could potentially be applied to additional management areas sharing similar ecological characteristics and harvest metrics. Published 2015. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Snowshoe hares ( Lepus americanus) are a primary prey species for Canada lynx ( Lynx canadensis) in western North America. Lynx management plans require knowledge of potential prey distribution and abundance in the western United States. Whether even-aged regenerating forests or multi-storied forests contain more snowshoe hares is currently unknown. During 2006-2008, we estimated snowshoe hare density in 3 classes of 30-70-year-old lodgepole pine ( Pinus contorta) and 4 classes of late seral multi-storied forest with a spruce ( Picea engelmannii)-fir ( Abies lasiocarpa) component in the Bridger-Teton National Forest, Wyoming. We recorded physiographic variables and forest structure characteristics to understand how these factors influence abundance of snowshoe hares. In many instances, snowshoe hares were more abundant in late seral multi-storied forests than regenerating even-aged forests. Forest attributes predicting hare abundance were often more prevalent in multi-storied forests. Late seral multi-storied forests with a spruce-fir component and dense horizontal cover, as well as 30-70-year-old lodgepole pine with high stem density, were disproportionately influential in explaining snowshoe hare densities in western Wyoming. In order to promote improved habitat conditions for snowshoe hares in this region, management agencies should consider shifting their focus towards maintaining, enhancing, and promoting multi-storied forests with dense horizontal cover, as well as developing 30-70-year-old lodgepole pine stands with high stem density that structurally mimic multi-storied forests. © 2012 The Wildlife Society. [ABSTRACT FROM AUTHOR]