Managing yards for mammals: Mammal species richness peaks in the suburbs

Increased urbanization drives habitat loss, yet residential land-use represents significant habitat potential for mammals and could provide connectivity between patches of green spaces. Diverse mammal communities exist across urban gradients, but it is unclear how mammal community composition varies within residential lands. We conducted a camera trapping study in 36 residential yards across an urban gradient to assess the relative contributions of the degree of urbanization in the land-use context versus parcel habitat features, such as vegetation structure, on mammal community diversity and composition. We hypothesized that land-use context would more strongly influence mammal community metrics than parcel features, and that there would be species-specific differences in response. We detected 14 non-domesticated mammal species and found that species richness peaked in the suburbs and tapered off at the rural and urban ends of the gradient in accordance with patterns seen in other taxonomic groups, yet rarely quantified in mammals. Large-bodied interior forest species were associated with rural sites, urban-dwelling species were associated with urban sites, and suburban sites had an overlap of species types. Although composition of mammal species in residential yards appears to be strongly related to land-use context, which is often outside of residents' control, management of parcel habitat features such as retention of large mature trees may facilitate connectivity between patches of habitat across urbanizing landscapes. Informed residential yard management remains an important tool for urban wildlife management in an era of global change.