by Yank Moore, Director of Conservation, Joseph Colbert, Wildlife Biologist, and Michael Brennan, University of Georgia PhD student
Jekyll Island is a beautiful place full of wildlife, but for one special snake, life there can be tricky, especially during the cold winter months. The Eastern Diamondback Rattlesnake (EDB), the largest rattlesnake in the world, faces many challenges as it moves around the island. Each year, these snakes travel between their foraging areas in search of winter homes. Sometimes, roads and trails fragment their natural habitats, making movement risky.
In other parts of the United States, including New Jersey and Arizona, wildlife managers have found a clever solution: creating winter sheltering sites in areas that prevent snakes from crossing dangerous zones.
Artificial refugia are safe underground shelters that snakes and other native species can use when natural hiding spots are limited or hard to find. These shelters provide snakes, insects, and even mammals a place to rest and stay warm enough to survive the cold winter months. Until recently, no one had used artificial refugia in the Southeast until a generous donor recognized the importance of what the conservation department and UGA Ph.D. student Michael Brennan were trying to accomplish and gave the team a jumpstart to optimize different designs.
Working with UGA, the conservation team identified spots where snakes are most at risk from roads or human activity. At each site, they dig a shallow hole and build a small “snake bunker” by strategically placing cinder blocks and a protective wooden roof. Once finished, the team covers the bunkers with soil and plants native grasses on top to help them blend into the landscape. The bunkers have two entrance holes, ideally facing southwest and northeast, to let in the winter sun during the morning and afternoon. Cameras and temperature sensors have recently been installed to track how snakes use these shelters and to see what other species share these essential refugia in winter.
The team has already piloted multiple designs, with another scheduled for deployment in the coming weeks. The first was placed deep in the brush adjacent to salt marsh habitat on an elevated ridge to expose it to direct sun and prevent flooding from high tides. To the untrained eye, this bunker is invisible and blends flawlessly into the landscape. Snakes, opossums, and native rodents have already been seen using artificial refugia, and the conservation team is hopeful it will continue to be used as temperatures drop.
The second design was deployed out of necessity. One of our tracked snakes was found in an active construction zone this past winter. Under those conditions, it would not have been able to escape the area during such cold temperatures. The conservation team decided to move the snake to the nearest safe space outside the construction zone into a newly built artificial refugia. Because of the snake’s natural homing tendencies during warmer weather, the team also created a pen enclosure to prevent it from reentering the construction site. The snake was observed basking on top of the bunker on warm sunny days and staying near the openings on cooler days, exactly what the refugia components were designed for.
Since the last bunker was easier to access and offered a more controlled environment, researchers were able to closely monitor it and learn how to improve future designs. With that success in mind, the next new and improved design being deployed in the coming days will utilize corrugated culvert pipe cut to keep a natural bottom, connecting two smaller artificial refugia at different elevations. This mimics gopher tortoise burrows, which EDBs and other native species are well documented using. Gopher tortoise burrows support hundreds of species in winter, where animals and insects can enjoy 65-degree temperatures during the coldest months. UGA students and the conservation team will continually monitor these underground wildlife bunkers for years to come to see how many species use them and whether the same individuals return to these shelters as their winter retreat.
If successful, these safe winter shelters will be used effectively for priority wildlife residents year after year, and the designs will be shared broadly with wildlife managers across the Southeast to help protect rattlesnakes and other species. By giving Eastern Diamondbacks and other native species a few cozy, well-placed homes, we can help them stay safe and keep Jekyll Island’s ecosystems healthy for years to come.
