Winter denning behaviour of striped skunks and interspecific den activity at their dens: implications for pathogen transmission

Abstract Context. Striped skunks (Mephitis mephitis) occur across a wide range of habitats in North America and co-occur with many wildlife that use similar denning structures. Few studies have quantified interspecific activity at striped skunk dens despite the concomitant implications for pathogen transmission due to direct and indirect contact at shared dens. Further, no studies have examined differences in striped skunk denning behaviour across an urban–rural gradient with various forms and degrees of human modification. Aims. Our study described striped skunk denning behaviour in the lower Midwestern United States and assessed interspecific activity at dens. Methods. We used radiotelemetry and camera traps to observe winter denning behaviour of radiocollared striped skunks and other sympatric species across an urban–rural gradient in southern Illinois, USA, during November–February 2018–2021. We examined correlations between striped skunks and other species captured in photos at dens. We tested for an effect of human modification on the number of dens used by striped skunks, and the effects of weather and landscape variables on striped skunk denning duration. Key results. Striped skunks used 3–21 unique dens during a single winter and denned consecutively in one location for 2–59 days. All individuals were observed denning for ≥8 consecutive days. Three striped skunks participated in communal denning, and ≤3 striped skunks were observed at a den concurrently. Eleven mammalian species were observed at striped skunk dens, and other species were present in 35.3% of photos. Striped skunk presence at a den was positively associated with Virginia opossum (Didelphis virginiana) presence. Human modification had no significant effect on the number of dens used by a striped skunk. Human modification, distance to stream/shoreline, and mean daily temperature had significant negative effects on striped skunk denning duration. Conclusions. We demonstrated that winter denning behaviour of striped skunks in southern Illinois, USA, fits into a latitudinal gradient of behaviour across North America, and dens are a shared resource where direct and indirect intraspecific and interspecific interactions occur. Implications. Weather and landscape features influenced winter denning behaviour of striped skunks and ultimately pathogen transmission potential at dens, trends that could potentially be seen in other urban-adapted species.