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Diamondback Terrapin
Malaclemys terrapin

Photo of an adult female Diamondback Terrapin courtesy of Mike Haramis, USGS.Named for the patterns on its top shell, the diamond back terrapin ranges along the Atlantic and Gulf coasts, from Cape Cod to Texas. It is believed to be the world’s only turtle that lives exclusively in brackish water, such as tidal marshes, estuaries and lagoons.

The diamondback shell is covered with scales or plates called scutes that bear deep, diamond-shaped growth rings. Black spots and wiggly marks, in patterns unique to each turtle, appear on its whitish skin. At about 7.5 inches, females are much larger than males which average 5 inches for the male. The terrapin dines mostly on snails, clams, crabs and marsh plants.

Photo of Diamondback terrapin courtesy of John WhiteFemales terrapins do not reproduce until they are 8 to 13 years old, moving from marsh creeks onto beaches and dunes in summer months to lay their pinkish-white eggs in 6-inch-deep nests in the sand. After 60 to 120 days, inch-long hatchlings emerge from the nest and enter the nearest waterway.

As the chief ingredient in terrapin soup, the species was decimated in the 1700s and 1800s. And while protective legislation is now in place, the species still faces many threats: The destruction of coastal marsh habitat, automobile traffic (while crossing the road to lay eggs), boat propellers, and other wildlife species that raid terrapin nests for eggs.

The diamondback terrapin is Maryland’s state reptile and the official mascot of the University of Maryland.

Photo of an adult female Diamondback Terrapin
caught in Tangier Sound, Chesapeake Bay, courtesy of Mike Haramis, USGS.

Photo of Diamondback terrapin in water courtesy of John White

For more information:
Turtles in Maryland

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