Multiscale burrow site selection of gopher tortoises (Gopherus polyphemus) in coastal sand dune habitat

The gopher tortoise (Gopherus polyphemus) is a keystone species in upland sandhill ecosystems of the SE United States, and its habitat requirements have been well documented. Few studies have been conducted on populations that occur in coastal sand dunes. Because of close proximately to the ocean and highly fragmented linear habitat, coastal populations of gopher tortoises are affected by unique landscape factors that are not observed in upland contiguous populations. In this study, burrow site selection of gopher tortoises in a coastal sand dune site was quantitatively modeled. Significant biological, environmental, and anthropogenic factors that may influence burrow site selection at fine and coarse spatial scales were identified. Land cover type, distance to edge, soil resistance, percentage of herbaceous cover, slope angle, and number of tortoise burrows have significant influences on burrow site selection probability. Factors that influence burrow locations in coastal populations thus might differ in importance from those that influence burrow locations in more spatially contiguous upland populations. Our results indicate that coastal gopher tortoise populations require sitespecific management that focuses on the limited availability of optimal burrow construction sites.