Urban and periurban mammal communities and its importance to conservation

Chupp, A. D., Roder, A. M., Battaglia, L. L., & Pagels, J. F. (2013). A case study of urban and peri-urban mammal communities: Implications for the management of National Park Service areas. Northeastern Naturalist, 20(4), 631-654.

The primary objective of this study was to compare urban and peri-urban mammal assemblages and relate variation in these communities to local differences in vegetation. We surveyed 15 locations in both urban and peri-urban habitats (n = 30). Boundaries of our survey areas coincided with those of National Park Service (NPS) areas in central Virginia. Over a 14-month period, we used five trap-types to document species in three guilds. A total of 9 and 15 species were documented at urban and peri-urban locations, respectively. Top predators Canis latrans (Coyote) and Felis rufus (Bobcat) were undetected at urban sites, while mesopredators were consistently more abundant. The absence of four small prey species and reduced abundances of the most common native generalist, Peromyscus leucopus (White-footed Mouse), were also associated with urban locations. Multivariate analyses of relative abundance data indicated significantly dissimilar mammal communities in urban and peri-urban locations. Shrub cover was highest in peri-urban locations, while grass cover was highest in urban sites—a pattern that was only marginally significant due to greater variability among these sites. The exotic grass Microstegium vimineum (Japanese Stiltgrass) was present at several urban sites and contributed to the complex relationship between percent grass cover and the small-mammal assemblages that we surveyed. Our results suggest that disturbances that reduce the recruitment of shrubs and other native plants and promote the spread of invasive grasses may have severe consequences for small-mammal communities. In addition, culturally preserved areas within both survey sites (i.e., battlefields planted with fescue grasses) were inhospitable to most small-mammal species and wildlife in general. In many NPS areas, there is great opportunity for development of adaptive management strategies that integrate ongoing NPS efforts to control invasive plant species with the enhancement of wildlife habitat in both culturally and naturally preserved areas. There is an urgent need for the conservation of native habitat in NPS areas and non-park sites threatened by urbanization. The primary focus of these efforts should include the control of exotic species and mesopredators, facilitation of native shrub recruitment, and, in many of these areas, the ecological restoration of historic sites. NPS lands in urbanized areas offer unique conditions for wildlife management and abundant opportunities for conserving native communities.