Habitat specialization by wildlife reduces pathogen spread in urbanizing landscapes

Urban areas are expanding globally, with far-reaching ecological
consequences, including for wildlife-pathogen interactions. Wildlife show
tremendous variation in their responses to urbanization; even within a
single population, some individuals can specialize on urban or natural
habitat types. This specialization could alter pathogen impacts on host
populations via changes to wildlife movement and aggregation. Here, we
build a mechanistic model to explore how habitat specialization in urban
landscapes affects interactions between a mobile host population and a
density-dependent specialist pathogen that confers no immunity. We model
movement on a network of resource-stable urban sites and
resource-fluctuating natural sites, where hosts are either urban
specialists, natural specialists, or generalists that use both patch
types. We find that, for generalists, natural and partially urban
landscapes produce the highest infection prevalence and mortality, driven
by high movement rates at natural sites and high densities at urban sites.
However, habitat specialization protects hosts from these negative effects
of partially urban landscapes by limiting movement between patch types.
These findings suggest that habitat specialization can benefit populations
by reducing infectious disease transmission, but by reducing movement
between habitat types could also carry the cost of reducing other
movement-related ecosystem functions such as seed dispersal and
pollination.