Burrowing for Data: Surveying Gopher Tortoises in Hillsborough County Nature Preserves

Gopher tortoise peering out of its shell

If you’ve ever been hiking on a Hillsborough County Nature Preserve, there’s a good chance you’ve seen a gopher tortoise munching some grass, sunning near the trail, or peering out of a burrow. The only tortoise native to the southeastern U.S., these slow-growing and long-lived reptiles are found in many dry upland areas of Hillsborough County. Gopher tortoises are a keystone species, meaning they have a disproportionately large effect on the ecosystem because hundreds of mammal, bird, reptile, and insect species find shelter in their burrows. Without these burrows to use as hiding spots, shade, and protection from fire, many sensitive and important species would not be able to survive. Sadly, development and suburban sprawl have fractured and degraded their upland habitat so much that gopher tortoises are now listed as a threatened species in Florida. 

To keep our gopher tortoise populations healthy and thriving, it’s important for the Conservation and Environmental Lands Management Department to know how our land management practices are affecting tortoises. That’s why the department's Research and Data have been surveying gopher tortoises in nature preserves with the help of other Conservation and Environmental Lands Management staff.

Gopher tortoise burrow

When the team surveys nature preserves for gopher tortoise, they aren’t looking for the tortoises themselves, but rather for their burrows. Making their way in orderly transects through vines, brush and undergrowth, surveyors scan the ground on either side for the telltale signs of gopher tortoise presence. They lift palmetto leaves, check under vines, and poke through groundcover in search of burrows, trails, and freshly dug sand. Once one team member finds a burrow, they determine whether or not the burrow is actively being used by a tortoise and carefully mark its location with a GPS unit. The Research and Data team then uses survey data to determine the area’s current distribution of gopher tortoise burrows.

Survey crew beginning a transect

Restoration projects, hardwood reduction, and the re-introduction of prescribed fire all benefit gopher tortoises by reducing the overgrowth of brushy groundcover plants and opening up overgrown areas, allowing tortoises to move, graze, and dig their burrows more easily. Surveying gopher tortoise populations before and after land management projects allows us to track how gopher tortoise populations are affected by changes in land management practices. 

Gopher tortoise surveys are just one important way in which the Research and Data team is gathering data on county nature preserves. The data collected by these tortoise surveys, as well as other wildlife and plant surveys, will give us important feedback on the effectiveness of land management projects and help inform the department’s goals and methods in the future.

Gopher tortoise grazing early in the morning