Birds and Burrows: Avifauna Use and Visitation of Burrows of Gopher Tortoises At Two Military Sites In the Florida Panhandle

The United States Department of Defense (DoD) has a dual mission of maintaining military readiness and stewardship of its natural resources. The DoD invests more than $334 million on land and species management on their properties, which support high levels of biodiversity and harbor a disproportionate number of threatened, endangered, and at-risk species. The gopher tortoise (Gopherus polyphemus) occurs on 28 DoD installations in the southeastern United States. Because more than 350 species have been documented to use their burrows, the gopher tortoise is considered a keystone species. However, few species of birds have previously been documented as burrow associates. In this study, we compare bird species richness, visitation frequency, and behaviors at gopher tortoise burrows at two Department of Navy properties (Santa Rosa County, Florida) that differed in size, training intensity, habitat diversity, and proportion of habitat suitable for gopher tortoises. We detected a total of 33 species of birds and documented previously unreported behaviors of foraging, dust bathing, and wing-flashing display behaviors at tortoise burrows. Although species richness between sites was not significantly different, frequency of visitation was greater at the site with less military training activity. Our findings underscore the importance of even small military installations in supporting local biodiversity and the need to further explore gopher tortoise burrows as a potential resource for avifauna.