The impacts of urbanization on wildlife in North America's largest urban forest

Abstract

Urbanization endangers more species in the United States than any other human activity as it dramatically modifies natural landscapes, fragments previously intact habitats, and is spreading rapidly. Species with specialized habitat requirements are more severely impacted by urbanization than other species and are usually absent from habitat fragments surrounded by an urban matrix. I studied the impacts of urbanization on a diverse wildlife community in the Great Trinity Forest Dallas, Texas, the largest urban forest in the United States. I used species distribution models to study the impacts of urbanization on swamp rabbit (Sylvilagus aquaticus) distribution. I used a landscape genetics approach to study the impact of urbanization on dispersal and gene flow in the swamp rabbit. I also studied the impact of urbanization on occupancy of breeding birds. The distribution of swamp rabbits was negatively associated with invasive species, but did not respond to other impacts of urbanization. I found that urbanization and highways significantly limited swamp rabbit gene flow and dispersal. And finally, I found that the avian community responded to anthropogenic impacts of urbanization in the matrix in diverse ways. To conserve urban avoiding species in urban habitat fragments it may be necessary to maintain large habitat tracts with uniform shapes that are not bisected by highways, and mitigate for the indirect effects of the matrix like noise and invasive species.