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A few weeks ago we were fortunate to find a Northern Diamondback Terrapin turtle hatchling on the Beekman Beach. The Diamondback turtles is the only turtle that inhabits coastal marshes with brackish water (mix of salt and fresh water) for their entire life. The northern diamondback is a medium-sized turtle that varies in length from only 4 to 5.5” in males to 6 to 9” in females. Females have a short, narrow tail while males have a relatively long, thick tail. Terrapin coloration varies highly between individuals, but all have a gray, brown, or black carapace (top of shell) and a lighter plastron (bottom of shell), which is a greenish-yellow. The skin is light to dark gray with black spots and other dark markings. Both sexes have a light colored upper mandible. They are named for their diamond shaped pattern on their carapace. Adult terrapins primarily eat mollusks and crustaceans, including snails, fiddler crabs, and mussels. They also eat blue crabs, green crabs, marine worms, fish, and carrion. Terrapins are more active during high tide, or when the marsh is often flooded. Northern diamondback terrapins exclusively inhabit coastal salt marshes, estuaries, tidal creeks and ditches with brackish water (a mix of both salt and freshwater) which is bordered by spartina grass. They are the only turtle in the world that is specially adapted to spend its entire life in this type of water. Studies have shown that terrapins exhibit a high level of site fidelity or they return to the same territory year. They also have a very small home range and some occupy the same small creeks year after year. Northern diamondbacks range from Cape Cod, Mass. to Cape Hatteras, N.C. Terrapins are cold-blooded or ectothermic. They hibernate during the winter and bury themselves at the bottom of or in the banks of creeks and ditches. They always have some mud covering them. Adult terrapins mate in early spring. Females lay clutches of 8-12 eggs from early June into mid-July in sandy beaches and other upland gravel areas that are above the high tide line. The eggs hatch in 61-104 days. The warmer the soil, the faster they hatch. The sex of hatchlings is determined by the temperature of the soil, the warmer the soil, the more females that are produced. This is known as temperature dependent sex determination. Hatchlings sometimes overwinter in nests and emerge the next year. After hatching they immediately head for vegetation, which helps provide cover and protection from predators, like gulls and crows. Males reach maturity at 5-8 years in age or when they are around 3-3.5″ in length, while females do not reach sexual maturity until they are approximately 9-10 years in age or are 6.5″ in length and weigh 2.3lbs. There are 6 other subspecies of terrapins the Carolina Diamondback Terrapin (M.t. centrata), the Florida East Coast Diamondback Terrapin (M.t. tequesta), the Mangrove Diamondback Terrapin (M.t. rhizophorarum), the Ornate Diamondback Terrapin (M.t. macrospilota), the Mississippi Diamondback Terrapin (M.t. pileata) and the Texas Diamondback Terrapin (M.t. littoralis). The species ranges from New England south to Florida and into Texas along the Gulf of Mexico. Today several major threats still threaten the survival of terrapins in New York. habitat loss, mortality from being drowned in crab traps, road mortality, and illegal collection all pose major threats to the health of the population. Hundreds of acres of terrapin habitat have been destroyed or altered by coastal development. Bulkheads restrict their natural movement and mosquito ditches have altered the tidal flow on our salt marshes. Roads all throughout the coastal area bisect terrapin habitat. Females are drawn to road shoulders because they mimic natural nest sites and in turn many are hit-by-car and killed each year while attempting to nest. High levels of contaminants have been found in the livers of terrapins. It is not clear how exactly they are affected by contaminants. Old, abandoned “ghost” traps create death traps for juvenile and male terrapins for years. It is unknown how many die from “ghost” traps. Human development has created ideal conditions for increased numbers of raccoons and skunks in coastal areas and increased predation of terrapin nests.