By Dan Quinn, Natural Resources Manager
Diamondback Terrapins: Diamondback terrapins are the only turtles in the U.S. that spend their entire lives in estuarine or brackish environments—waters where salt and freshwater mix. Each summer, female terrapins crawl up to the Jekyll Island Causeway looking for high ground to lay their eggs and many are hit and killed by cars while searching for nesting sites.
Since 2008, the Jekyll Island Authority has monitored the causeway during nesting season to track population trends, with the intention of reducing road mortality and developing new conservation strategies. In 2022, JIA installed a barrier fence, with the help of the Jekyll Island Foundation (JIF) and Animex, at one of the busiest crossing spots at the western end of the causeway. The results were dramatic: road mortalities at this site dropped from an average of 12.7 terrapins per year to just 2.3. Instead of crossing the road, most terrapins were stopped by the barrier fence and promptly nested alongside the fence instead.
However, this success led to a new challenge—raccoons and other predators quickly began targeting these concentrated nesting sites, resulting in heavy egg losses. To address this, in 2025 the conservation team added a 235-foot electric wire along the marsh side of the fence to deter raccoons. The fence was set up to allow terrapins to pass through and nest under the electric fence. This simple addition proved highly effective: of 109 nests found plundered, only one (0.9%) was located beneath the electric wire. The team plans to expand this project in the future and are seeking funding opportunities. To help with this goal, click here.
