These water turtles are named for the diamond pattern on top of their shell, but the overall pattern and coloration varies greatly by species. Their shell coloring can vary from browns to greys, and their body color can be grey, brown, yellow, or white. All have a unique pattern of wiggly, black markings or spots on their body and head.

pet turtle - Diamondback terrapin pet turtle - juvenile Diamondback turtle / en.wikipedia.org

The species is sexually dimorphic in that the males grow to approximately 5 inches, while the females grow to an average of around 7.5 inches, though they are capable of growing larger. The largest female on record was just over 9 inches in length. Specimens from regions that are consistently warmer in temperature tend to be larger than those from cooler, more northern areas.

Historic uses
Terrapin is derived from an Algonquian Indian word torope meaning "edible turtle living in fresh or brackish water." Terrapin was so plentiful in the 1700s that Maryland slaves protested the excessive use of this food source as their main protein. Late in the 1800s, demand for turtle soup claimed a harvest of 89,150 pounds from Chesapeake Bay in one year. In 1899, terrapin was offered on the dinner menu of Delmonico's Restaurant in New York as the third most expensive item on the extensive menu. A patron could request either Maryland or Baltimore terrapin at a price of $2.50. Although demand was high, by 1920 the harvest of terrapin, during one year, reached only 823 pounds. The diamondback is also the official mascot of the University of Maryland, College Park. Adopted in 1932 at the urging of Dr. H. Curly Byrd, the diamondback replaced then-current mascot, "the Old Liners."

Life cycle
Adult diamondback terrapin mate in the early spring, and clutches of 5-12 eggs are laid in sand dunes in the early summer. They hatch in late summer or early fall. Maturity in males is reached in 2-3 years at around 4.5 inches in length; it takes longer for females: 6-7 years at a length of around 6.75 inches.

Turtle habitat
The habitat of the diamondback terrapin extends from Cape Cod to Texas along the Atlantic and Gulf coasts. It is believed to be the only turtle that survives in brackish water areas. Its predators include skunks, muskrats, raccoons and crows. These small aquatic turtles nest on land and require access to dry soft sand or soil to deposit their eggs. If this species of turtle is extirpated from its environment it would have a difficult time repopulating its former habitat.

Behavior

Normally active during the day, this species may haul out on rocks or the banks of tidal creeks to bask. Terrapins range widely while foraging for food; however, they are often found in the same small area over consecutive years. Adults hibernate communally on the muddy bottom of creek beds. In southern climates the water turtles may become active on warm winter days, but in northern populations they remain in dormancy.

Diet
The diamondback terrapin lives on a diet of mollusks, fiddler crabs, and occasionally small fish. The terrapin can crush mollusk shells due to the bony plates they have on their upper and lower mandibles.

Reproduction

The female is considerably larger than the male and may therefore choose her mate. In temperate regions, nesting occurs from mid-May to late July, but southern populations may nest as late as September. The females can store sperm in their oviducts for at least four years; however, fertility rates drop precipitously after the second year. The elongate eggs (1.0–1.7 in [26–42 mm] long and 0.6–1.1 in [16–27 mm] wide) have flexible shells. Two or more clutches of up to 20 eggs are deposited annually in the sandy dunes above the winter high tide mark. The eggs hatch after 61 to 104 days of incubation. Sex is dependent upon the incubation temperature; mostly males are produced from 77 to 84°F (25 to 29°C), however at 86°F (30°C) the hatchlings are all female. Most hatchlings emerge in the autumn and are presumed to hibernate aquatically, but some hatchlings may overwinter in the nest.

Subspecies
Carolina Diamondback Terrapin, Malaclemys terrapin centrata (Latreille, 1802)
Texas Diamondback Terrapin, Malaclemys terrapin littoralis (Hay, 1904)
North Atlantic Diamondback Terrapin, Malaclemys terrapin maximus (Tucker, 1986)
Ornate Diamondback Terrapin, Malaclemys terrapin macrospilota (Hay, 1904)
Mississippi Diamondback Terrapin, Malaclemys terrapin pileata (Wied-Neuwied, 1865)
Mangrove Diamondback Terrapin, Malaclemys terrapin rhizophorarum (Fowler, 1906)
East Coast Florida Diamondback Terrapin, Malaclemys terrapin tequesta (Schwartz, 1955)
Northern Diamondback Terrapin, Malaclemys terrapin terrapin (Schoepf, 1793)

Status
The diamondback terrapin is the state reptile of the U.S. state of Maryland and is the official mascot of the University of Maryland (the Maryland Terrapins or "Terps" for short). The species was once considered a delicacy to eat and was hunted almost to extinction. Due to this it is listed as an endangered species in Rhode Island, is considered a threatened species in Massachusetts, and is considered a "species of concern" in Georgia, Delaware, Louisiana, North Carolina, and Virginia, but it holds no federal status.

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