Status of Historical Translocations of Gopher Tortoises Outside of Their Geographic Range in Central Alabama

Abstract

The gopher tortoise (Gopherus polyphemus) is a species of concern in the southeastern United States, and its distribution is within the range of the longleaf pine (Pinus palustris). One conservation strategy within the state of Alabama has been translocation of adult tortoises to other areas with longleaf pine and sandy soils, including areas outside the current accepted species’ range. Prior examples of such tortoise translocations occurred in two counties in central Alabama: one in the 1960s in Macon County and another in the 1980s in Autauga County. Both introductions occurred near the Coastal Plain fall-line, which is deemed the northernmost landmark designation that tortoises were historically presumed to reside. The status of these translocated tortoise populations had not been recently assessed. Therefore, we surveyed the two locations, captured individuals, and qualitatively examined the minimum known number of alive adult tortoises. We found populations of tortoises at both translocation sites, including evidence of reproduction and recruitment. Notably, we found two marked tortoises (one at each of the two relocation sites) from the original translocations, indicating that translocated tortoises survived in these new areas for 30 and 49–56 years, respectively. Although inference about translocation success is limited by overall low tortoise projected densities, our results suggest tortoise populations can persist in areas of Alabama outside their mapped geographic range, including on soil types not documented previously.