Diamondback Terrapin (Malaclemys terrapin)


Class: Reptilia
Order: Chelonia
Family:    Emydidae
Size:    Length: 4 to 9 inches (10 to 23 cm)
Weight: Up to 2 pounds (0.9 kg)
Diet: Snails, crustaceans, fish, insects and the shoots of water plants
Distribution: North America
Young:  4 to 18 eggs, several times per year
Animal Predators:  Raccoons and dogs; skunks, crows and muskrats go after hatchlings
IUCN Status: Lower Risk, Near Threatened
Terms: Young: Hatchling
Lifespan: Up to 40 years or longer



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

·       Terrapin is a Native Algonquian word meaning edible turtles that live in fresh or brackish water.

·       Turtles are the only reptiles that do not have teeth, as well as being the only reptiles with hard shells.

·       In the 1700s, slaves on Maryland’s eastern shore were fed so much terrapin meat that they protested.



Diamondback terrapins are named for the diamond-shaped patterns on their upper shell. The upper shell is light brown to black in colour, while the underside of the shell is yellow to greenish grey. Their whitish skin is speckled with black spots. Females are larger than males. 



Diamondback terrapins are found along the eastern coast of the United States from Massachusetts to the Florida Keys, and along the Gulf Coast from Florida to Texas. They inhabit marshes, lagoons, channels, tidal flats and coastlines. Terrapins are at home in saltwater, fresh or brackish water, but need fresh water to drink. 


Feeding Habits

They eat snails, crustaceans, fish, insects and the shoots of water plants. Their powerful jaws have ridges that allow them to open the shells of their prey. 



Terrapins mate while in water. The female later climbs up on the bank and digs a hole in the sand or mud, where she lays up to 18 light pink, leathery eggs and covers them with mud to keep them warm. She may lay several more clutches per season. The eggs are incubated for two to three months. Colder temperatures (26°C/78.8°F) seem to produce mostly male offspring, while warmer temperatures (32°C/89.6°F) produce females. Hatchlings are approximately one inch (2.5 cm) long and often fall victim to predators such as raccoons, skunks, crows and muskrats. Males reach sexual maturity at three to four years, but females are not fully mature until they reach six or seven.  



Diamondback terrapins are shy turtles that spend most of their time in the water, coming out only when they want to bask in the sun, or when it is time for them to lay their eggs. They are sociable amongst their own species and even lie on top of each other. A female may lie on top of a male, although she can be up to twice his size. They are quick and efficient swimmers and will re-enter the water if disturbed. In the northern areas of their range, they hibernate by congregating in mud holes. Terrapins in the southerly ranges do not hibernate, but are active year round. 



In the 1900s, diamondback terrapins were close to extinction, but many American states put laws into force to protect them from being over-harvested, as they were popular gourmet food. Some states have even created laws to protect the beach grass that surrounds the nesting area of the terrapins. Threats to diamondbacks now include estuarine pollution, automobiles and commercial and recreational crab traps, in which they may get caught and drown. 













Diamondback Terrapin Wildlife Fact File, IM Pub, US