TIMES-UNION (Jacksonville, Florida) 15 April 07 Studies aimed at helping turtles (Teresa Stepzinski)
Brunswick: A small turtle with a big role in the Coastal Georgia ecosystem is the focus of two new scientific studies and a voluntary pilot program to prevent it from drowning in crab traps.
The diamondback terrapin is unique to the coast, and protected by Georgia law as an "unusual species."
The terrapins are unique because they are the only ones in the United States that live their entire lives in the salt marshes and estuary, said Brad Winn, senior wildlife biologist with the Georgia Department of Natural Resources.
The department is coordinating two studies involving the University of Georgia and volunteers from Chatham County.
Diamondback terrapins and two studies, including a voluntary pilot program examining the effectiveness of Terrapin Excluder Devices in crab traps, will be the subject of a public meeting from 6 to 8 p.m. Monday at the Tybee gymnasium on Tybee Island.
For more information, call the Georgia Department of Natural Resources Coastal Resources Division at (912) 264-7218 or go to the department's Web site, www.gadnr.org, and click on Coastal Resources.
The studies are intended to gather information about the size and range of the diamondback terrapin population, which varies throughout Georgia's coastal creeks and 400,000 acres of salt marsh, Winn said.
"Some areas will be chock-full of them and others are devoid of them," Winn said.
Information collected in the studies also will help biologists gauge threats facing the terrapins, Winn said.
In addition to the danger from natural predators such as raccoons, the terrapins get run over as they cross roadways to nesting sites and are hurt from water pollution and loss of habitat, Winn said.
The crab trap threat
The program could help eliminate at least one man-made hazard for the turtles: drowning in crab traps.
A voluntary program based at Tybee Island will investigate the effectiveness of Terrapin Excluder Devices designed to prevent the turtles from entering crab traps.
The program, aimed at recreational crabbers, was requested by Paul Wolff, a member of the Tybee Island City Council who also is a member of the natural resources department's Coastal Advisory Council.
Terrapin excluders are mandated by law in New Jersey and Delaware. Other states are looking at the idea, marine fisheries officials said.
Crabbers don't want the terrapins in their traps because they limit the catch, Winn said.
The 2-foot by 2-foot wire traps have four entrances that blue crabs crawl through to get at the bait in the center.
"Crabbers don't like them because if terrapins get into a trap, they act like a deterrent to the crabs and the crabs won't go in," Winn said.
The DNR is certain that a lot of terrapins die in crab traps, he said.
"The terrapin are attracted to the traps by the bait, but once inside they cannot escape and are drowned," he said.
Pilot program
Terrapins tend to live in small, narrow creeks close to uplands that are also increasingly popular sites for waterfront homes with private docks.
Many people use commercial-style crab traps from those docks, said Doug Haymans, special projects coordinator for the department's Coastal Resources Division.
The department plans to distribute 2,000 Terrapin Excluder Devices - enough for 250 traps - to crabbers who participate in the pilot program. Although the study is based on Tybee Island and focused on recreational crabbers, others statewide would be welcome to participate in the program, he said.
A public meeting will be held Monday night on Tybee Island to discuss the studies and crab trap program.
Although much remains unknown about the diamondback terrapin, biologists do know it has a vital role in the coastal ecosystem.
"As long as diamondback terrapin are out there, you can be pretty sure that the rest of the system is functioning as it should be," said Mark Dodd, a department wildlife biologist and turtle researcher. "It's important because it is a good indicator species that lets us know about the overall health of the ecosystem."
The terrapin was one of the species studied at the former LCP chemical plant in Brunswick to identify and determine the extent of toxins released into the adjacent salt marsh, he said.
Here are some quick facts about the animal:
- Diamondback terrapins are protected under Georgia law as an "unusual species."
- It is illegal to kill or possess one in Georgia.
- The terrapin has been documented from Maine to Texas along the Atlantic and Gulf coasts.
- Considered a gourmet delicacy, it was nearly wiped out in the 1700s and 1800s because of over-harvesting.
- It is distinguished by the diamond-shaped pattern on its shell.
- The terrapin has whitish or light gray skin with black spots and wiggly marks. It also appears to have a "grin" on its face.
- The animal spends most of its time in the water. It comes on land to bask in the sun and to lay eggs.
- Females have a shell averaging about 71/2 inches.
- Males have a shell averaging about 5 inches.
- Mature females generally lay about four to 20 eggs in sand above the high tide line from late April through early July.
- The babies generally hatch after three months, and measure about 1 inch when they emerge from the nest.
- Diamondback terrapins eat insects, snails, clams, small crabs and some salt marsh plants.
- Threats include: habitat destruction; being struck by cars as they cross roads to nest; drowning in crab traps; predators such as raccoons, skunks, muskrats and crows.
- Sources: Georgia Department of Natural Resources, University of Georgia and University of Delaware Graduate College of Marine Studies.
Studies aimed at helping turtles