Responses of a forest-dwelling terrestrial turtle, Terrapene carolina, to prescribed fire in a Longleaf Pine ecosystem

Abstract

Prescribed fire is commonly used as a tool to meet a range of forest management goals. Owing to their limited movement abilities, terrestrial turtles are likely to be at high risk of injury and mortality, and to experience other fitness consequences with population-level implications from fire. Using radiotelemetry, we studied the responses of Eastern Box Turtles, Terrapene carolina carolina, to prescribed fire management in a sandhills Longleaf Pine forest system over a five-year period and compared our results to a nearby population in an unburned coastal plain location. Individual variation in turtle survival was strongly dependent on how frequently and extensively the areas were burned, with annual survival rates of 94.5% in unburned areas decreasing to 45.9% in the most extensively burned areas. Turtles at the fire-maintained sandhills site had annual survival rates 4.9% less than at the unburned coastal plain site, and females had annual survival rates 6.8% less than males. Survival varied seasonally, with greatest mortality rates in winter and spring, especially among females. Growth rates and body condition did not differ between sites, nor did they vary according to fire extent and frequency at the fire-maintained site. Although mortality was greater and spatially variable at the fire- maintained site, annual survival rates across the site (86–90% for females and males, respectively) were comparable to other stable populations of T. carolina. The lesser than expected mortality rate at the fire-maintained site was likely the result of turtles’ strong selection of mesic hardwood forests near bottomlands and streams – habitats that may serve as refugia from fire. In areas where T. carolina conservation is a priority, land managers should integrate maintenance of fire refuge habitats into burn planning to minimize unintended negative impacts to this imperiled species.