City divided: Unveiling family ties and genetic structuring of coyotes
in Seattle
Abstract
Linear barriers pose significant challenges for wildlife gene flow,
impacting species persistence, adaptation, and evolution. While numerous
studies have examined the effects of linear barriers (e.g., fences,
roadways) on partitioning urban and non-urban areas, understanding their
influence on gene flow within cities remains limited. Here, we
investigated the impact of linear barriers on coyote (Canis latrans)
population structure in Seattle, Washington, where major barriers (i.e.,
interstate highways and bodies of water) divide the city into distinct
quadrants. Notably, private allele analysis underscored limited
interbreeding among quadrants. When comparing one quadrant to the next,
there were up to 16 private alleles within a single quadrant,
representing nearly 22% of the population allelic diversity. Our
analysis revealed weak isolation by distance, and despite being a highly
mobile species, genetic structuring was apparent between quadrants even
with extremely short geographic distance between individual coyotes,
implying that Interstate 5 and the Ship Canal act as major barriers.
Lack of gene flow may stem from the perceived risk of crossing these
barriers, as even despite the presence of structural connectivity
features (e.g., bridges and underpasses), functional connectivity may
remain limited. Urban areas provide refuge and resources for wildlife
but come with tradeoffs, as evidenced by restricted gene flow and
potential long-term impacts on population viability and evolution. This
study advances our understanding of gene flow and its consequences in
cities, a crucial component for bolstering wildlife conservation and
management in rapidly urbanizing environments.