Bay Critter Profile: Diamondback Terrapin

The beautiful Diamondback terrapin can thank Prohibition and the Great Depression for its continued existence. The female Diamondback terrapin was the main ingredient in "Terrapin Stew," all the rage in the late 1800s and early 1900s. After Prohibition went into effect in 1920, alcohol, a key ingredient in terrapin stew, was no longer readily available. At the same time, decades of unregulated over-harvesting of Diamondbacks had made them dangerously scarce, driving up prices and making them affordable only to the very wealthy. Much of that wealth disappeared with the Great Depression in 1929, and the era of the Diamondback terrapin as a culinary delicacy among the eastern elite came to an end.

Found locally along Long Island's shores, the Diamondback terrapin lives and breeds in the salt marshes and tidal tributaries along the Atlantic and Gulf coasts from Massachusetts to Texas. The Diamondback is the only North American turtle that lives exclusively in brackish water. They prefer unpolluted tidal areas (who doesn't?) and therefore are good indicators of healthy wetland systems.

The Diamondback terrapin population is slowly rebounding from the over-harvesting of a century ago. These days, human activity is its primary threat. The draining and filling of marshland to build houses and roads leaves the female Diamondback terrapin without a safe place to nest, forcing her to cross roads and highways as she searches for a suitable place to lay her eggs during the early summer nesting season. Shoreline bulkheads, increasingly common along our Peconic and South Shore bays, create insurmountable obstacles for the little Diamondback terrapin and are another hindrance to safe nesting. Raccoons, foxes, herons and other birds are natural threats to terrapins, particularly hatchlings.

Female Diamondback terrapins typically grow to be 8-9 inches long and mature later than males, who only grow to about 5-6 inches at adulthood. Their life expectancy varies from 25 to 40 years, though they can live as long as 50 years. The skin of terrapins is its fingerprint: markings on no two animals are alike. Black spots and dashed or curly lines create a unique design.

It is illegal to collect Diamondback terrapins without a license in New York State. If you are a boater, navigate carefully in tidal creeks and estuaries where terrapins gather in late spring to mate at the water's surface. While driving on coastal roads in June and July, look out for terrapins crossing the road to nest and do your best to avoid them and help the Diamondback’s comeback.