The diamondback terrapin is a medium-sized turtle which lives in salt marshes and tidal rivers along the eastern coast of the United States from Florida to Cape Cod, Massachusetts. The turtles with which we work are all from Sandy Neck Beach, located on the northern coast of Cape Cod.
In late spring and early summer, the female terrapins leave the salt marsh and nest on the nearby sand dunes. Females dig nests in the sand and lay an average of 8-12 eggs. The location where a female chooses to lay her eggs is critical to the survival of her offspring.
Currently, diamondback terrapins are protected under the Massachusetts Endangered Species Act as “threatened.” A threatened species is defined by the Commonwealth of Massachusetts as “native species which are likely to become endangered in the foreseeable future, or which are declining or rare as determined by biological research and inventory.”
Two major causes have been identified as the reasons for the dwindled populations of diamondback terrapins in Massachusetts. In the early 1900s, they were considered a culinary delicacy and were harvested in large numbers. Needless to say, since receiving environmental protection, terrapins are no longer harvested in Massachusetts. However, the terrapin populations have still not recovered to numbers that existed prior to the early 1900s. The second major reason for the terrapins’ threatened status is due to the development or modification of their habitat by humans, which occurs even today regardless of their protected status.
On average, less than "20%" of turtle eggs laid survive through the first year. One of the main reasons turtles don’t survive is that they are preyed upon by skunks, raccoons, crows, seagulls, large fish, coyotes, and other predators. However, as turtles get older and larger, fewer animals can eat them and therefore they are more likely to survive.
By rearing captive young turtles, or headstarting them, we hope to give vulnerable hatchlings a second chance at survival. Hatchling diamondback terrapins are about the size of a quarter. In the wild, hatchling turtles emerge from their nests beneath the sand, and walk to the salt marsh. Many don’t make it. Those that do, will brumate (or hibernate) for the winter, not beginning to grow until the following spring. In contrast, the headstarted turtles are kept warm and fed over the winter. When they are released in the spring, they will have reached a body size comparable to a three or four year-old terrapin in the wild. Although there is still a danger that they may be preyed upon, it is reduced because the turtles will be too large for some of their predators.
Although the primary purpose of this project is to give these hatchling turtles a head start, it also provides a great opportunity to study the behavior of these young turtles. Very little is known about turtle life history from the time they hatch until they become large enough to be captured in nets. This accounts for the first seven years of their lives, nicknamed “the lost years” by well known turtle biologist, Archie Carr. By having these turtles in the lab, it affords us a unique opportunity to study them.