Landscape genetics of the New England cottontail: Effects of habitat fragmentation on population genetic structure and dispersal

The New England cottontail (Sylvilagus transitionalis) is a species of conservation concern. Population recovery will require knowledge of genetic structure and dispersal patterns. To this end, I used microsatellite loci to assess genetic structure at two spatial scales: across the entire range (broadscale) and within the northernmost population (finescale). Range-wide, cottontails are separated into five distinct populations. There was little evidence of gene flow among populations and they have experienced extensive genetic drift. Several populations had comparatively reduced genetic diversity. Intensive fine-scale surveys revealed four genetically differentiated populations. Interstate-95 is a dispersal barrier, though other major roads did not impact gene flow. Greater fragmentation resulted in stronger spatial genetic structure. Dispersal is female-biased, yet female dispersal may be limited by patch isolation. Management efforts should focus on increasing habitat and restoring connectivity. Additional surveys may be needed across the range to identify population-specific dispersal barriers that may require special mitigation