Texas Diamondback Terrapin (Malaclemys terrapin littoralis)

Description
Shell length of the Texas diamondback terrapin ranges from 4-5.5 inches (10 to 14 cm) in males to 6-9 inches (15 to 22 cm) in females. Distinguishing characteristics include a dark carapace (upper shell) and pale plasteron (lower shell), diamond-shaped scutes (plates that form the carapace), and strongly webbed feet and unusually large back feet.
Life History
Texas diamondback terrapins are solitary except when breeding. Its predators include humans, raccoons, skunks and crows. An individual female breeds every four years or so. Mating season is in the spring. After mating in the water, females come ashore and dig a tear-shaped nest in the sand above the high-tide line and lay four to 18 eggs. If temperatures are warmer, her nest will produce more females; if temperatures are cooler, then the nest will produce more males. Eggs incubate 60 to 100 days depending on local conditions, especially temperature. If the eggs do not hatch before winter sets in, the hatchlings will spend the winter in the nest and will emerge when the weather warms. Males reach sexual maturity at three years, females at six years. The Texas diamondback terrapin can live up to up to 40 years.

Occasionally, adult diamondbacks may dig into the mud to hibernate over the cold winter months. During the day terrapins spend most of their time in the water or basking in the sun. At night terrapins bury themselves in mud. Crabs, shrimp, bivalves, fish and insects make up the diet of the Texas diamondback terrapin. Diamondbacks can adjust their water needs depending on how salty the water is. When their systems become too salty, diamondbacks secrete salt from their tear ducts to help regulate their salt levels. Texas diamondbacks are one of seven subspecies of Malaclemys terrapin recognized by scientists.
Habitat
Diamondback terrapins prefer brackish or salt water. They are the only turtle found in estuaries, tidal creeks, and saltwater marshes where the salinity comes close to that of the ocean.
Distribution
This species is found from Louisiana to Corpus Christi Bay.
Other
Texas diamondback terrapins were once hunted to the brink of extinction because many people thought that they were especially delicious in soup. Some believe that Prohibition helped save terrapins. Turtle soup was made with wine during the 1920s. When Prohibition laws made possessing wine illegal, turtle soup fell out of favor and thousands of trapped turtles were released into the ocean. Today, most terrapins are killed by speeding cars or become trapped in baited blue crab traps and drown.