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JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.Abstract: Management of high-density suburban deer populations requires knowledge of survival and movement to predict population trends. However, natural and human-induced influences on survival and movement of suburban deer are poorly understood. Therefore, we marked 208 (60 bucks, 148 does) white-tailed deer (Odocoileus virginianus) from forest preserves in Chicago, Illinois, USA (1994-1998). Seasonal and annual survivorship was >0.80 for 114 does and 13 bucks. Deer-auto collisions produced the highest mortality rates, 0.10 (95% CI 0.06 to 0.14) and 0.17 (95% CI 0.0 to 0.37). Spring dispersal for does was 7% (3 of 41) for fawns and 6% (5 of 83) for yearlings and adults; and for bucks it was 50% (8 of 16) for fawns and 7% (2 of 30) for yearlings and adults. All dispersals were <9 km, except for 1 parous doe that moved 33.9 km. Doe home ranges averaged 51 (95% CI 40.5 to 61.5), 26 (95% CI 22.0 to 30.0), and 32 (95% CI 19.6 to 44.4) ha for winter-spring, summer, and fall, respectively. A priori, we developed a set of 10 logistic regression models for suburban doe survival relative to home range size and traffic exposure indices. Using Akaike's Information Criterion (AIC), the best models included covariates reflecting home range size and traffic exposure. Inference across a 290% confidence set of survival models indicated substantial spatial heterogeneity in mortality risk for suburban does. High survival and philopatry by suburban deer apparently contribute to their overabundance in metropolitan areas. JOURNAL OF WILDLIFE MANAGEMENT 66(2):500-510

Free-roaming cats are a common element of urban landscapes worldwide, often causing controversy regarding their impacts on ecological systems and public health. We monitored cats within natural habitat fragments in the Chicago metropolitan area to characterize population demographics, disease prevalence, movement patterns and habitat selection, in addition to assessing the possible influence of coyotes on cats. The population was dominated by adults of both sexes, and 24% of adults were in reproductive condition. Annual survival rate was relatively high (S=0.70, SE=0.10), with vehicles and predation the primary causes of death. Size of annual home range varied by sex, but not reproductive status or body weight. We observed partitioning of the landscape by cats and coyotes, with little interspecific overlap between core areas of activity. Coyotes selected for natural habitats whereas cats selected for developed areas such as residences. Free-roaming cats were in better condition than we predicted, but their use of natural habitat fragments, and presumably their ecological impact, appeared to be limited by coyotes through intraguild competition.

Coyotes appear to be one of the few mammalian carnivores that occur in urban areas, although their true relationship with urbanization remains poorly understood. We summarize results from a long-term study of the urban ecology of coyotes in the Chicago metropolitan area to determine the degree of synanthropy for this species and discuss the subsequent management implications for human-coyote conflicts. Local population densities were slightly higher, and survival rates for pups were five times higher compared to rural populations. In contrast to demographic patterns, behavioral responses to urbanization, including home range size, avoidance of developed land cover, activity budget, and diet, were not consistent with synanthropy, even for coyotes located in the urban matrix. We discuss the management implications of the paradoxical relationship coyotes have with people and cities.

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Neonatal survival influences growth of unhunted populations of suburban white-tailed deer ( Odocoileus virginianus (Zimmerman, 1780)). Understanding the interaction of habitat and survival may inform conservation efforts and studies of life history of cervids at high density. We chose two forest preserves representative of forests in suburban Chicago. We radio-marked 56 neonates (1999–2001) to investigate mortality and habitat use. Through 1 July, 21 of 29 (72%) neonates and 6 of 22 (27%) died mostly because of predation by coyotes ( Canis latrans Say, 1823). Akaike’s information criterion suggested that optimal mark–recapture models of survival contained covariates reflecting differences by preserve and timing chosen to coincide with behavioral change from hiding to accompanying the doe. Survival was lower during early parturition (0.26–0.78) relative to the latter part (0.90–0.96). Early fawns (hiders) at one site had lower survival (0.26–0.29) than fawns at the other (0.78). Lower survival associated with larger home ranges, greater movement, and reduced understory cover, suggesting that hiding cover may mediate fawn survival in the presence of predators. Our study demonstrates spatial heterogeneity in population biology of suburban deer and suggests that site-specific differences may influence neonate survival in the face of coyote predation.

Raccoons (Procyon lotor) are considered synanthropic, with high densities reported from urban landscapes. However, little information is available on population density and demography within the urban matrix. To better understand how urban land-use patterns influence raccoon density and demographic patterns, we sampled raccoons at multiple, replicated sites across an urban landscape. Density differed by land-use type (F 2,17 ¼ 4.66, P ¼ 0.027): urbanized sites, x ¼ 4.96 AE 2.64 raccoons/km 2 , range ¼ 1.25-10.00 raccoons/km 2 ; urban open sites, x ¼ 14.84 AE 6.35 raccoons/km 2 , range ¼ 3.00-29.25 raccoons/ km 2 ; rural open sites, x ¼ 15.50 AE 4.66 raccoons/km 2 , range ¼ 13.00-20.25. Although we found no clear patterns in sex ratio, reproductive condition, or body condition, we observed differences in age structure among urban open, rural open, and urbanized sites. The most striking difference was the absence of older animals at urbanized sites and relatively low numbers of young individuals at urban open sites. Raccoons were the dominant mesocarnivore in open fragments, but less so in the urban matrix. Spatial variation in density across urban landscapes is likely influenced by site level differences in abundance of anthropogenic resources and differences in habitat quality. Furthermore, the association between changes in land-use and population age structure may have reflected different mortality sources across the landscape. Our results illustrate that wildlife species considered synanthropic may have complex relationships with urban landscapes. ß 2012 The Wildlife Society.