From backyard to backcountry: changes in mammal communities across an urbanization gradient.

This article focuses on the effects of urbanization, measured by housing density, on medium- to large-bodied mammal communities along a gradient from wilderness to suburban areas in Missoula, Montana. Using 178 motion-activated trail cameras deployed from 2019 to 2020, the study applied multispecies occupancy models, Poisson count models, and analyses of diel activity patterns to assess how urbanization influences mammal occupancy, species richness, relative abundance, and temporal behavior. Results showed a linear decline in species richness with increasing housing density, stronger negative occupancy effects on larger-bodied mammals, and highest relative abundance in suburban areas driven mainly by White-tailed Deer. Additionally, urbanization altered nocturnal activity patterns in some species, with Black Bear and White-tailed Deer becoming more nocturnal, while Red Fox and Northern Raccoon became less nocturnal, underscoring the importance of preserving wild areas to maintain diverse mammal communities.