Magle S.B.,Urban Wildlife Institute |
Salamack K.A.,Wildlife Habitat Council |
Crooks K.R.,Colorado State University |
Reading R.P.,Denver Zoological Foundation
Biodiversity and Conservation | Year: 2012
Urbanization and habitat fragmentation have the potential to influence bird communities. In addition, these phenomena, as well as ongoing lethal control measures, have also greatly reduced the range of the black-tailed prairie dog (Cynomys ludovicianus) since the beginning of the 20th century. Although prairie dogs are highly interactive species that can influence avian communities, few studies have investigated whether these interactions persist in urban settings. Our goal was to investigate the relative impacts of habitat fragmentation and prairie dogs on bird communities within an urban matrix. We performed bird surveys on 20 habitat fragments (10 colonized by prairie dogs, 10 uncolonized by prairie dogs) distributed throughout the Denver metropolitan area, and calculated Shannon-Weiner diversity and richness of all birds and native species, as well as total counts of grassland birds and raptors. Diversity, richness, and counts of many species increased with increasing fragment connectivity, and decreased on fragments isolated for longer periods of time. Avian diversity and richness did not differ between fragments with and without prairie dogs, suggesting that this element of the ecological role of prairie dogs is not fully retained in urban habitat. Future studies of the role of prairie dogs as keystone species in urban systems should include other taxa as well as consider the influence of the urban matrix surrounding prairie dog habitat. Our results emphasize that conservation of urban avian diversity should focus on landscape connectivity as well as local habitat features. © 2012 Springer Science+Business Media B.V.
Ricketts T.H.,University of Vermont |
Lonsdorf E.,Urban Wildlife Institute
Ecological Applications | Year: 2013
Natural ecosystems benefit human communities by providing ecosystem services such as water purification and crop pollination. Mapping ecosystem service values has become popular, but most are static snapshots of average value. Estimating instead the economic impacts of specific ecosystem changes can better inform typical resource decisions. Here we develop an approach to mapping marginal values, those resulting from the next unit of ecosystem change, across landscapes. We demonstrate the approach with a recent model of crop pollination services in Costa Rica, simulating deforestation events to predict resulting marginal changes in pollination services to coffee farms. We find that marginal losses from deforestation vary from zero to US$700/ha across the landscape. Financial risks for farmers from these losses and marginal benefits of forest restoration show similar spatial variation. Marginal values are concentrated in relatively few forest parcels not identified using average value. These parcels lack substitutes: nearby forest parcels that can supply services in the event of loss. Indeed, the marginal value of forest parcels declines exponentially with the density of surrounding forest cover. The approach we develop is applicable to any ecosystem service. Combined with information on costs, it can help target conservation or restoration efforts to optimize benefits to people and biodiversity. © 2013 by the Ecological Society of America.
Moore C.T.,U.S. Geological Survey |
Lonsdorf E.V.,Urban Wildlife Institute |
Knutson M.G.,U.S. Fish and Wildlife Service |
Laskowski H.P.,U.S. Fish and Wildlife Service |
Lor S.K.,U.S. Fish and Wildlife Service
Journal of Environmental Management | Year: 2011
Adaptive management is an approach to recurrent decision making in which uncertainty about the decision is reduced over time through comparison of outcomes predicted by competing models against observed values of those outcomes. The National Wildlife Refuge System (NWRS) of the U.S. Fish and Wildlife Service is a large land management program charged with making natural resource management decisions, which often are made under considerable uncertainty, severe operational constraints, and conditions that limit ability to precisely carry out actions as intended. The NWRS presents outstanding opportunities for the application of adaptive management, but also difficult challenges. We describe two cooperative programs between the Fish and Wildlife Service and the U.S. Geological Survey to implement adaptive management at scales ranging from small, single refuge applications to large, multi-refuge, multi-region projects. Our experience to date suggests three important attributes common to successful implementation: a vigorous multi-partner collaboration, practical and informative decision framework components, and a sustained commitment to the process. Administrators in both agencies should consider these attributes when developing programs to promote the use and acceptance of adaptive management in the NWRS. © 2010 .
Lehrer E.W.,Urbana University |
Lehrer E.W.,Urban Wildlife Institute |
Schooley R.L.,Urbana University |
Whittington J.K.,Urbana University
Canadian Journal of Zoology | Year: 2012
Understanding effects of urbanization on biodiversity requires integrated assessments of demographic and behavioral responses by species, including urban-adapter species. Past research on mammalian responses to urbanization has emphasized predators, but prey species could respond to additional factors including variation in predation risk. We examined spatial heterogeneity in real and perceived risk across an urbanization gradient by comparing survival rates, causes of mortality, and antipredator behavior of adult woodchucks (Marmota monax (L., 1758)) within an agricultural landscape in Illinois from 2007 to 2009. Survival rates were higher, and effects of urbanization were stronger, during the inactive season. Rural woodchucks primarily died from predation or costs associated with hibernation, whereas urban woodchucks mainly died from vehicle collisions or unknown reasons. Mean levels of antipredator behavior were unrelated to urbanization, but among-individual variation in vigilance levels increased in urban areas, which may reflect increased spatial variation in disturbance levels within urban environments. Distances from burrows while foraging and flight initiation distances also were unrelated to urbanization, suggesting that urban woodchucks were not strongly habituated to humans. Our research provides insights into demographic and behavioral responses to urbanization, and constraints to responses, by an urban-adapter species.
Magle S.B.,Urban Wildlife Institute |
Samuel M.D.,U.S. Geological Survey |
Van Deelen T.R.,University of Wisconsin - Madison |
Robinson S.J.,University of Wisconsin - Madison |
Mathews N.E.,University of Wisconsin - Madison
PLoS ONE | Year: 2013
Wildlife disease transmission, at a local scale, can occur from interactions between infected and susceptible conspecifics or from a contaminated environment. Thus, the degree of spatial overlap and rate of contact among deer is likely to impact both direct and indirect transmission of infectious diseases such chronic wasting disease (CWD) or bovine tuberculosis. We identified a strong relationship between degree of spatial overlap (volume of intersection) and genetic relatedness for female white-tailed deer in Wisconsin's area of highest CWD prevalence. We used volume of intersection as a surrogate for contact rates between deer and concluded that related deer are more likely to have contact, which may drive disease transmission dynamics. In addition, we found that age of deer influences overlap, with fawns exhibiting the highest degree of overlap with other deer. Our results further support the finding that female social groups have higher contact among related deer which can result in transmission of infectious diseases. We suggest that control of large social groups comprised of closely related deer may be an effective strategy in slowing the transmission of infectious pathogens, and CWD in particular. © 2013 Magle et al.