Displaced Gopher Tortoises Might Survive On Islands, Say Researchers

A UF study of gopher tortoises on small islands near St. Augustinecould reveal whether displaced colonies can be successfully relocatedto similar sites in Florida and other states, said Dana Ehret, adoctoral student with UF’s Institute of Food and Agricultural Sciences.

“Not much is known about gopher tortoise populations on smallislands, because researchers have pretty much overlooked them,” Ehretsaid. “For example, we don’t know how common these populations are, howthe tortoises cope with the constant exposure to salt or how theymanage to keep their burrows from being flooded by the higher watertable.”

Gopher tortoise burrows are a familiar sight in rural inland areasfrom Louisiana to South Carolina, the tortoise’s native range, he said.Marked by piles of sand at their entrances, the burrows can be 10 feetdeep and 40 feet long. More than 360 other species use the burrows forshelter.

The tortoises are protected by Florida law and developers haveseveral options when specimens are found in areas slated forconstruction, Ehret said. They can build at a distance from burrows,move tortoises to other parts of the same property, relocate tortoisesto distant properties or obtain permits allowing work to proceed inexchange for financial support of tortoise conservation.

The latter option preserves tortoises and habitat elsewhere, butanimals on the development site are often lost when burrows collapse,he said.

Developers often prefer to obtain the permits due to timeconstraints, Ehret said. Some tortoise experts consider the permits anacceptable – though not ideal – option, and believe present relocationefforts have not succeeded as a conservation measure.

“Relocation sounds like a great idea, but in practice it’s hadproblems,” Ehret said. “For developers, there’s a lot of work involvedin capturing tortoises and arranging for them to be placed on otherproperty. Researchers are concerned that if the new habitat isn’t justright the tortoises will leave, and may end up injured or killedanyway.”

Another drawback to current relocation efforts is that tortoisesplaced on privately owned land could be displaced again by futuredevelopment, said Mike Moulton, a UF associate professor of wildlifeecology and conservation and Ehret’s faculty adviser. The UFresearchers believe a better option may be to relocate tortoises onsmall islands likely to remain undeveloped, either due to governmentprotection or simply because they are unsuitable for development.

The UF study focuses on gopher tortoise populations on five smallislands in the Atlantic Intracoastal Waterway, he said. Despite thereptiles’ size – up to 15 pounds – and ponderous appearance, they floatand are sometimes observed swimming.

Hundreds of islands are found throughout the waterway, which is aseries of bays, estuaries and navigation channels reaching from Miami,Fla. to Norfolk, Va., Moulton said. Other islands along the Atlanticand Gulf coasts might also be suitable as tortoise habitat.

“We hope that with the right preparation, some of these islandscould serve as homes for gopher tortoises and possibly for beach mice,indigo snakes and other species impacted by development,” he said. “Itmight be possible to construct new islands specifically for thispurpose.”

This fall, Ehret will help monitor an experimental effort torelocate Florida gopher tortoises to an island home. A Flagler Countydeveloper has worked with state agencies for several years to arrangethe relocation, which is aimed at establishing a permanent tortoiserefuge, Ehret said.

“Just by coincidence, this project had been developing independentlyof our UF research and I jumped at the chance to get involved,” Ehretsaid. “By observing newly introduced tortoises in a coastal habitat wemay learn things that help us focus our own research.”

Gopher tortoise management efforts need to be stepped up throughoutthe Southeast, said Craig Guyer, a biological sciences professor atAuburn University in Auburn, Ala. Loss of habitat is the most seriousthreat facing gopher tortoise populations in all six states where theanimal is found.

“Florida is 10 years ahead of everyone else in terms of bumping intothis problem and being forced to come up with solutions,” Guyer said.“The idea of setting aside land for permanent gopher tortoise habitatis catching on here in Alabama and I’ll be interested to see if thatproves viable in coastal areas in Florida.”