Diamondback Terrapin Research Team
"Terrapin" is a term from the Algonquian word, "torope" to describe edible turtles that live in fresh or brackish waters. One such species is Malaclemys terrapin, the diamondback terrapin, the only known U.S. turtle to inhabit estuaries, coastal rivers and mangrove swamps. It can be found from Cape Cod, its northernmost habitat, to Corpus Christi Texas. Its range is confined to the continental U.S. Seven subspecies have been identified along the Atlantic and Gulf coasts. The Northern Diamondback, M. terrapin terrapin, found from Cape Cod, MA to Cape Hatteras and the Carolinas, is the local resident subspecies that we are studying. The diamondback gets its name from the concentric rings formed on the scutes that comprise the shell or carapace.
The diamondback terrapin was once abundant. The species was first jeopardized as a result of its use as a food source. Terrapin soup became a very popular culinary item and about 100 years ago, diamondback terrapins were hunted to near extinction to be used in recipes for soups and stews. As tastes have changed and as legislation has been drafted to protect the species, there has been a gradual increase in their numbers. The diamondback terrapin is still faced with threats. Its natural predators, such as raccoons, skunks and crows, dig up nests, feed on eggs and eat hatchlings. Plant roots and maggots destroy eggs that contain developing hatchlings. Human activities pose additional hurdles for the species. Terrapin hunting is still legal in some states, although a license is required and the industry is regulated. Many females are hit by cars as they make their way across roads to lay their eggs. They drown in crab pots and are killed or injured by boat propellers. And as the shoreline has become a popular location for vacation homes and resorts, terrapins are losing important coastal marsh habitat needed for nesting.
Researchers at Massachusetts Audubon Society's Wellfleet Bay Wildlife Sanctuary (WBWS) have been conducting studies, gathering field data, protecting terrapins and educating the public about the species and its habitat for over 22 years. Wheaton College has partnered with WBWS to study and protect the species. At Wheaton, we have recruited interns, received grants and been actively involved in terrapin research and conservation for the past few years.
We have raised terrapins from hatchlings to study their early growth and behaviors. We are studying their responses to stimuli such as light and heat. Before the hatchlings are released in their natal marshes, we attach radio transmitters to follow their travels throughout their summer activity cycle.
Recently, modern molecular genetic methods have been employed to complement ecological studies. The molecular methods have the power to assess the genetic makeup of plant and animal species within and between populations in order to examine genetic diversity and answer questions about population substructure, gene flow, kinship, taxonomy and phylogenetic relationship. In our laboratory, we have begun to study the genetic diversity of terrapins within the Wellfleet Bay ecosystem and in the Cape Cod area. When coupled with the general population and habitat studies that are ongoing, a genetic profile of this population will be essential in assessing the population substructure.
View article and additional photos.
Contact information:
Barbara Brennessel, Ph.D.
bbrennes@wheatoncollege.edu
Phone: 508-286-3954
Biology Department
Wheaton College
Norton, MA 02766 USA