Herpetology/Crocodilians and Turtles

This page contains information on members of Crocodylia and Testudines (Chelonia) on the Herpetology List. For more general information about the event, see Herpetology.

Order Crocodylia

There are 3 families of Crocodylia, with 23 species total. These families are:

• Gavialidae (2 species: gharials and false gharials)
• Crocodylidae (crocodiles, with 14 species in 3 genera)
• Alligatoridae (alligators and caimans, 7 species in 4 genera)

Alternate names	(alternate names)
Etymology	(etymology)
Physical Appearance	(physical appearance)
Life Cycle	(life cycle)
Ecology, Habitat and Diet	(ecology)
Behavior and Locomotion	(behavior)
Conservation Status and Efforts	(conservation status/efforts)
Distribution	(distribution)
Miscellaneous Information	(miscellaneous)

Family Crocodylidae (crocodiles)

Alternate names	True crocodiles
Etymology	From the Greek word krokodilos (krokē "pebble" + drilos "worm").
Physical Appearance	Differences from alligators: Have narrow and long heads with V-shaped snouts (as opposed to wide and short heads with obtuse snouts in alligators). The upper and lower jaws are the same width. The lower teeth are visible when the mouth is closed, but the lower jaw's large fourth tooth fits into a pocket in the upper jaw. There is more webbing on the toes of the hind feet (as opposed to webbing going halfway to the toe tip), and crocodiles are more tolerant to saltwater due to specialized glands for filtering out salt, which are present but nonfunctional in alligators. Aquatic adaptations: Have a streamlined body, webbed feet, and a palatal flap, which blocks water from entering the mouth. There is a special path from the nostril to the glottis in the palate which skips the mouth. Nostrils are closed while submerged. A third eyelid (nictitating membrane) protects the eyes underwater. Have vibration sensors and touch receptors that help find prey underwater. Can hold their breaths for 4-15 minutes. Size: Sizes range from 1.5-1.9 m (dwarf crocodiles) to over 7 m and 1000 kg (saltwater crocodiles). Eating: Have 80 teeth. Teeth are set in sockets. Are polyphyodonts, able to replace each tooth up to 50 times (a small replacement tooth and odontogenic stem cell is next to each full grown tooth). Teeth are sharp, suited for piercing and holding onto flesh, not tearing flesh off of animals. Strongest bite of any animal by far – in the wild, a Nile crocodile measured 22,000 N (compare to 3,600 N by a hyena), and in a laboratory setting, a saltwater crocodile measured 16,000 N. Have stiff jaw muscles, with large amounts of space inside the skull for the jaw muscle. Adapted for clamping down but not for opening. Have gizzards (grind up food before it enters the stomach). Senses: Eyes, ears, and nostrils on top of heads, which lets crocodiles stay almost completely submerged. Very good night vision. Very developed olfactory (smell) senses. Good hearing senses.
Life Cycle	Live for 35-75 years. Egg: Nests are usually holes in soil or mounds of soil elevated well above the water level. Around 30-60 eggs are hatched. Incubation takes 9-10 weeks. Sex is temperature-dependent. Young: The babies break through the eggshells with their egg teeth and begin making high-pitched noises to tell the mother to remove the vegetation. The adults pick their young up in their mouths and carry them to the water (swallowing the remaining shells), and they are left to fend for themselves. There is a high mortality rate: young crocodiles can fall prey to raccoons, birds, etc. Crocodiles mature after 2-8 years. Adult: Male American crocodiles start courtship in January/February by slapping their heads quickly and repeatedly until a female raises her tail and snout, inviting the male. The male then vibrates his body in the water. The mother places vegetation on top of the next to hide and incubate the eggs.
Ecology, Habitat and Diet	Habitat: Semi-aquatic. Live in tropical environments. Most prefer freshwater wetland environments with rivers and ponds, but some prefer saltwater. Relationship with environment: Build dams and holes that trap water. Clean up the river by eating animal carcasses. Help ensure the rivers are functioning and well-balanced in their habitats. Diet: Carnivorous: usually feed on vertebrates (fish, reptiles, birds, mammals, etc.). Some also feed on invertebrates such as mollusks and crustaceans. Crocodiles can go months without feeding if their body temperatures remain low.
Behavior and Locomotion	Sensitive to cold (unlike alligators). Higher levels of aggression than other crocodilians. Systematically patrol their territory. Spend night in the water. Bask in the sun or cool off in shade during daylight. May remain underwater for up to two hours not moving (adapted to high levels of lactic acid in their blood). Often rest with their mouth gaping to cool themselves down (although it may also have a social function). Young crocodiles (siblings) wrestle with each other. Prey by ambushing. Estivate during summer. Locomotion: Easily exhausted on land. Can move quickly over short distances. Land speed record 17 km/h by an Australian freshwater crocodile galloping. Some species can gallop. Crocodiles can reach 10-11 km/h by "belly running". Crocodiles can also "high walk", holding legs straight and upright under the body (can reach up to 5 km/h like this).
Conservation Status and Efforts	Some species are critically endangered due to habitat loss being destroyed by logging and industry. Poaching for hides also contributes to the declining population. Crocodile farms are being set up to reduce poaching and repopulate endangered species. Status by species: American crocodile (Crocodylus acutus) Vulnerable (Moved from threatened to endangered by USWS on March 20, 2007) Slender-snouted crocodile (C. cataphractus) Critically Endangered Orinoco crocodile (C. intermedius) Critically Endangered Freshwater crocodile (C. johnsoni) Least Concern Philippine crocodile (C. mindorensis) Critically Endangered Morelet's crocodile (C. moreletti) Least Concern Nile crocodile (C. niloticus) Least Concern New Guinea crocodile (C. novaeguineae) Least Concern Mugger crocodile (C. palustris) Vulnerable Saltwater crocodile (C. porosus) Least Concern Cuban crocodile (C. rhombiter) Critically Endangered Siamese crocodile (C. siamensis) Critically Endangered West African crocodile (C. suchus) ? Dwarf crocodile (Osteolaemus tetraspis) Vulnerable
Distribution
Miscellaneous Information	Unable to stick out their tongues due to a membrane restricting tongue movement. Record time for a crocodile spent underwater is eight hours in freezing conditions. Crocodiles are the only reptile to have a four-chambered heart (others have three-chambered hearts).

Family Alligatoridae (alligators and caiman)

There are two extant species of alligator: Alligator mississippiensis (the American alligator) and A. sinensis (the Chinese/Yangtze alligator). There are six extant species of caiman: Caiman yacare (the Yacare caiman), C. crocodilus (the spectacled caiman), C. latirostris (the broad-snouted caiman), Melanosuchus niger (the black caiman), Paleosuchus palpebrosus (Cuvier’s dwarf caiman), and Paleosuchus trigonatus (the smooth-fronted caiman).

Etymology	From the Spanish el lagarto (the lizard).
Physical Appearance	Aligators: Have a slow metabolism. Most of the muscle in jaw is evolved to bite and grip prey (muscles for closing are exceptionally powerful, and muscles for opening are very weak, able to be held shut using several rolls of duct tape for transportation). Gizzard stones often found in stomachs. Unidirectional movement of air through the lungs (like fish and birds) while most other amniotes have bidirectional/tidal breathing (air moves in one direction through the parabronchi, exits lung through inner branch, oxygen exchange takes place in extensive vasculature around the parabronchi). Have muscular, flat tails that propel them while swimming. Two kinds of white alligators are albino and leucistic: they are practically impossible to find in the wild and survive only in captivity (e.g. Aquarium of the Americas; New Orleans has leucistic alligators that were found in a Louisiana swamp in 1917). The Chinese alligator is fully armored (including the belly). Differences from crocodiles: See #Family Crocodylidae (crocodiles) Size: Average adult American alligator weight is 360 kg (790 lb) up to over 450 kg (990 lb). Average height is 4.0 m (13.1 ft) up to 4.4 m (14 ft). The largest ever American alligator was found in Louisiana and was 5.84 m (19.2 ft) long. Average adult male Chinese alligator rarely weighs over 45 kg (99 lb) or exceeds 2.1 m (6.9 ft). Color: Black or dark olive-brown with white undersides (strongly contrasting white or yellow marks on juveniles which fade with age). Caimans: Scaly skin. Average maximum 6-40 kg (13-88 lb) except for M. niger, which can grow to 1100 kg (2400 lb) and 5 m (16 ft). P. palpebrosus grows to 1.2-1.5 m (3.9-4.9 ft). Differences between alligators and caimans: Caimans lack the bony septum between nostrils which alligators have, have ventral armor composed of overlapping bony scutes formed from two parts united by a suture, are relatively longer and more slender teeth, and have calcium rivets on scales that make hides stiffer and less valuable.
Life Cycle	Adult life span not measured. An alligator at least 80 years old (named Muja) in Belgrade Zoo in Serbia brought from Germany in 1937 is the oldest alligator in captivity. Eggs (summer): Female builds nest of vegetation (decomposition provides heat). Chinese alligators have the smallest eggs of any crocodilian. Sex of offspring fixed within 7-21 days of the start of the incubation (less than 30 degrees Celsius or 86 degrees Fahrenheit produces all females, and greater than 34 degrees Celsius or 93 degrees Fahrenheit produces all males). Nests constructed on leaves tend to be hotter (more males) than those constructed on wet marshes. Young: Baby alligators use egg teeth to get out of egg. Hatchlings have a ratio of five females to one male. Females weigh significantly more. The mother defends the nest from predators and assists hatchlings to water, providing protection for about a year if they remain in the area. Adult alligators regularly cannibalize younger individuals: after the outlawing of alligator hunting, populations quickly rebounded because of the higher rate of survival of juveniles. Female caimans build large nests (can be over 1.5 m wide) and lay 10-50 eggs which hatch in around 6 weeks. Females take their young to a shallow pool of water where they can learn how to hunt and swim. Mating season (late spring): Mature at length of 1.8 m (6 m). "Bellowing choruses" in April and May (large groups of animals bellow together for a few minutes a few times a day usually one to three hours after sunrise, accompanied by powerful blasts of infrasound). Males do a loud head-slap. Exhibit group courtship ("alligator dances")
Ecology, Habitat and Diet	Effect on biodiversity: Increase plant diversity and provide habitats for other animals during drought by constructing alligator holes in wetlands. Feed on coypu and muskrats, which cause severe damage to wetlands through overgrazing. Keystone species in the Everglades. Predators: Apex predator (may determine abundance of prey species like turtles and coypu). Caimans have few natural predators (humans are main predators). Jaguars and anacondas prey on smaller caiman species. Habitat: Alligators intolerant to salinity, ponds, marshes, wetlands, rivers, lakes, swamps, brackish environments. Diet: Eat foliage and fruit in addition to their usual diet of fish and meat. Young alligators eat small prey (e.g. fish, insects, snails, crustaceans, and worms) while mature alligators eat bigger prey (e.g. larger fish such as gar, turtles, mammals like coypu and muskrats, birds, deer, and other reptiles). Main diet is smaller animals that they can kill and eat in one bite. May kill larger prey by grabbing and dragging into the water to drown. Will consume carrion if hungry enough (larger ones known to ambush dogs, Florida panthers, and black bears). Consume bigger food through allowing it to rot or using a "death roll" (biting and then convulsing/spinning wildly until bite-sized chunks are torn off: tail flexing to a significant angle relative to body is crucial). Caimans hunt insects, birds, and small mammals and reptiles, in addition to a great deal of fish.
Behavior and Locomotion	Less dangerous to humans than crocodiles (generally timid and tend to walk/swim away). Provoked into attack by people approaching alligators or alligator nests. Attacks are few but not unknown. Feeding alligators is illegal in Florida because eventually alligators will lose their fear of humans, which is a greater risk for both alligators and humans. Chinese alligator are the most docile of all crocodilians. Large males are solitary territorial. Smaller alligators are in larger numbers close to each other (have a high tolerance for alligators of similar size). Largest (both genders) defend prime territory. Caimans are fairly nocturnal. Locomotion: Capable of short bursts of speed in very short lunges. Move on land through: Sprawl: A forward moment with the belly making contact with the ground and is used to transition to high walk or to slither over web substrate into water. High walk: Up on fours limbs forward motion with belly well up the ground. On hind legs: Cannot maintain for long distances, balance on hind legs and semi-step forward as a forward or upward lunge.
Conservation Status and Efforts	American alligator: Least Concern Chinese alligator: Critically Endangered (IUCN Red List) with only a few dozen believed to be left in the wild (far fewer than in zoos). Chinese alligators are preserved by the Rockefeller Wildlife Refuge and Miami MetroZoo and are a CITES Appendix I species (extreme restrictions on trade and exportation). In 1999, there were an estimated 150 Chinese alligators left in the wild. Most remaining wild individuals live in the Anhui Chinese Alligator Nature Reserve. In danger from habitat pollution and reduction (because of rice paddies and poaching for medicinal purposes). Some are exterminated (some farmers consider them a threat). In 1979, Anhui Research Center for Chinese Alligator Reproduction was founded and had a breeding success, turning 200 to 10,000. The Changxing Nature Reserve and Breeding Center for Chinese Alligators housed almost 4,000 alligators.
Distribution	Distributions for species of alligator and caiman: American alligator Texas to North Carolina (all of Florida and Louisiana, southern parts of Georgia, Alabama, Mississippi, coastal North and South California, East Texas, southeast corner of Oklahoma, and the southern tip of Arkansas). Louisiana has the largest alligator population. Southern Florida is the only place where both alligators and crocodiles live. Chinese alligator Eastern China, found only in the Yangtze River valley and parts of adjacent provinces. Black caiman Slow-moving rivers and lakes that surround the Amazon basin. Caimans in general Central and South America
Miscellaneous Information	Raised commercially for meat and skin (leather for luggage, handbags, shoes, belts, etc.). Helps with ecotourism. In 2010, the Archbishop of New Orleans ruled that alligator meat is considered fish for purposes of meat abstention.

Order Testudines/Chelonia

Alternate names	(alternate names)
Etymology	(etymology)
Physical Appearance	(physical appearance)
Life Cycle	(life cycle)
Ecology, Habitat and Diet	(ecology)
Behavior and Locomotion	(behavior)
Conservation Status and Efforts	(conservation status/efforts)
Distribution	(distribution)
Miscellaneous Information	(miscellaneous)

Family Chelydridae (snapping turtles)

Chelydridae belongs to the suborder Cryptodira and has two extant genera, Chelydra and Macrochelys. Chelydra has three species: C. serpentina (the common snapping turtle), C. acutirostris (the South American snapping turtle), and C. rossignonii (the Central American snapping turtle). Macrochelys has anywhere from one to three extant species, M. suwanniensis (the Suwannee snapping turtle, previously though to be part of M. teminckii), M. teminckii (the alligator snapping turtle), and M. apalachicolae (the Apalachicola snapping turtle, which is not generally recognized as a different species from M. teminckii).

Etymology	C. rossignonii is in honor of the French-born coffee grower Jules Rossignon. M. temminckii is in honor of Dutch zoologist Coenraad Jacob Temminck.
Physical Appearance	Common snapping turtles: Powerful beak-like jaws. Highly mobile head and neck (origin of the specific name serpentina). Can bite handler even if picked up from the side of the shell or hind legs. Sharp claws (like dog claws except they cannot be trimmed). Claws are used for digging and gripping, not attacking—the legs are not strong enough for a swiping motion—or eating—no opposable thumbs. Rugged muscular build. Ridged carapace, usually 25-47 cm (9.8-18.5 inches) in adults. Usually weigh 4.5-16 kg (9.9-35.3 lb). The heaviest caught in the wild was 34 kg (75 lb). The heaviest native freshwater turtle in the north. Plastra are around 22.5 cm (8.9 inches) long, and almost all common snapping turtles that weigh over 10 kg (22 lb) are old males. They continue to grow throughout life and have snorkel-like nostrils positioned on the top of the snout. The have large heads relative to their bodies, broad and flat carapaces, cruciform plastra (giving them more efficient leg movement for walking along the bottom of ponds and streams), and the longest tails of any turtle. Alligator snapping turtles: One of the heaviest freshwater turtles in the world. Large heavy heads and long, thick shells with three dorsal ridges of large scales (osteoderms) making them appear like an ankylosaurs. Solid grey/brown/black/olive-green and usually covered in algae. Radiating yellow patterns around eyes that break up outlines of eyes and keep turtles camouflaged. Star-shaped arrangement of fleshy, filamentous "eyelashes". In 1937, an alligator snapping turtle weighing 183 kg (403 lb) was found in Kansas (not verified). They continue to grow throughout life and are generally 8.4-80 kg (19-176 lb) and 35-80.8 cm (13.8-31.8 in). Males are typically larger, and specimens over 45 kg (99 lb) are generally very old males. Only the giant softshell turtles of Chitra, Rafetus, and Pelochelys reach a comparable size. The male’s cloaca extends beyond the carapace edge while the female’s is at the carapace edge or nearer to the plastron. The male’s tail is thicker at the base because of the reproductive organs. The inside of the mouth camouflaged with a vermiform (worm-shaped) appendage on the tip of the tongue used to lure fish (Peckhamian mimicry). Alligator snapping turtles have a bite force about the same level as humans relative to size (158 plus or minus 18 kgf, 1550 plus or minus 180 Newtons, or 348 plus or minus 40 lbf). They can still bite through handle of a broom but rarely can bite human fingers clean off. They have four marginal scutes (unlike C. serpentina).
Life Cycle	High and variable mortality of embryos and hatchlings. Delayed sexual maturity. Extended adult longevity. Iteroparity (repeated reproductive events). Low reproductive success per reproductive event. Common snapping turtles: Females mature later at a larger size (15-20 years) in northern populations compared to southern populations (12 years). Maximum age of over 100 years. Eggs are vulnerable to crows, minks, skunks, foxes, and raccoons. They are laid in sandy soil some distance from the water. Females lay 25-80 eggs each year, guiding the eggs into the nest using the hind feet and covering the nest with sand for incubation and protection. Incubation period is temperature dependent (8 to 18 weeks). Eggs overwinter in the nest in cooler climates. Hatchlings are vulnerable to the aforementioned predators as well as herons (mostly great blue herons), bitterns, hawks, owls, fishers, bullfrogs, large fish, and snakes. Mate from April to November (peak June and July). Females can hold sperm for several seasons. Alligator snapping turtles: Believed to be able to live to 1200 (although 80-120 is more likely). Typically live between 20 and 70 years in captivity. Mature at around 12 years, with a size of around 8 kg (18 lb) and 33 cm (13 in). Mate yearly (early spring in the south and later spring in the north).
Ecology, Habitat and Diet	Habitat: Freshwater – common snapping turtles prefer shallow ponds and streams (some in brackish environments such as estuaries) and are extremely cold tolerant, remaining active under ice during winter and capable to diving to over 2-3 meters.. They come on land only to lay eggs. Predators: Large, old, male common snapping turtles are at the top of their food chain. C. serpentina adults are sometimes ambushed by northern river otters during hibernation. Reported predators are coyotes, black bears, alligators and larger cousins, and alligator snapping turtles. Diet: The common snapping turtle consume both animal and plant matter and is an important aquatic scavenger. Common snapping turtles are also active hunters that prey on anything they can swallow (e.g. invertebrates, fish, frogs, other reptiles like snakes and smaller turtles, unwary birds, and small mammals), which can be detrimental to breeding waterfowl since they will occasionally take ducklings and goslings. They are a somewhat flatulent species due to their varied diet. The alligator snapping turtle is also opportunistic and almost entirely carnivorous, relying on catching food and scavenging. Alligator snapping turtles will eat anything they can catch and target abundant and easily caught prey, e.g. fish, fish carcasses, molluscs, carrion, and amphibians. They are also known to eat snakes, crayfish, worms, water birds, aquatic plants, and other turtles and on occasion prey on aquatic rodents like nutria and muskrats or even small mammals like squirrels, opossums, raccoons, and armadillos.
Behavior and Locomotion	C. serpentina is combative when out of water. It will make a hissing sound and release a musky odor when stressed. It is likely to hide itself under sediment when in water. Common snapping turtles sometimes bask by floating on surface with only the carapace exposed. They also bask on fallen logs in early spring in the north and may lie beneath a muddy bottom with only the head exposed in shallow waters (stretching their long necks to the surface for an occasional breath). If an unfamiliar species is encountered (such as humans), they may become curious and survey the situation (rarely may bump their nose on a person’s leg) if an unfamiliar species is encountered. Travel extensively over land to reach new habitats (can be driven to move by pollution, habitat destruction, food scarcity, overcrowding, etc.) or to lay eggs. Hibernating snapping turtles do not breathe for (in the northern region) more than six months. They can get oxygen by pushing their head out of the mud and allowing gas exchange between mouth membranes and throat membranes (extrapulmonary respiration). They utilize anaerobic pathways if there is not enough oxygen to burn sugars and fat. However, there is an undesirable side-effect from this process that comes in spring known as oxygen debt. M. temminckii hunts diurnally by keeping its mouth open and imitating the motions of a worm using its tongue (the mouth is then closed with tremendous force and speed). Younger turtles catch minnows this way while larger turtles must catch more food more actively. There are no reported human deaths by alligator snapping turtles, and they are not prone to biting. They most often hunts at night, and adults have been known to kill and eat small American alligators. Locomotion: Moving sideways is significant slower. They are capable of swimming up, swimming down, and walking.
Conservation Status and Efforts	Least concern: however, their life history is sensitive to disruption by human activity (target for surveys, ID of major habitats, investigation and mitigation of threats, education of public including landowners, etc. from governmental departments, universities, museums, and citizen science projects). M. temminckii is a threatened species (CITES III limits exportation from the US and international trade) and is protected by state law in Kentucky, Indiana, Illinois, and Missouri, as well as labeled “in need of conservation” in Kansas.
Distribution	Distribution by species: C. acutirostris Colombia, Costa Rica, Ecuador, Honduras, Nicaragua, and Panama C. rossignonii Belize, Guatemala, Honduras, and Mexico M. suwanniensis The Suwannee river (a major wild backwater river that runs through South Georgia southward into Florida) M. teminckii Primarily in southeastern US waters
Miscellaneous Information	It is a misconception that snapping turtles can be picked up safely by the tail (doing so will harm the turtle’s tail and vertebral column). Trying to rescue a snapping turtle by getting it to bite a stick and then dragging it out of danger will severely scrape the legs and underside of the turtle (leading to deadly infections). The safest way to pick up a snapping turtle is using a shovel or gasping the carapace above the back legs or picking up the corners of a blanket or tarp with the turtle in the middle. They are raised on some turtle farms in China. Common snapping turtles may be invasive in Italy and Japan from unwise exotic pet releases. Snapping turtles are a traditional ingredient in turtle soup (however, this may be toxic due to bioaccumulation). They are sometimes captive bred as an exotic pet; however, they do not make good pets – hand feeding is dangerous, and extreme temperatures result in the turtle refusing to eat. It is illegal to keep M. temminckii as a pet in California (where alligator snapping turtles do not naturally occur). Alligator snapping turtles were released into Czech Republic and Germany. Four were caught in Bohemia, and they are considered an invasive species in Oregon (where one was captured and euthanized in October 2013 in the Prineville Reservoir).

Family Kinosternidae (musk and mud turtles)

Kinosternidae belongs to the suborder Cryptodira and is split into two subfamilies, Kinosternon (consisting of subfamilies Kinosternoninae – with Kinosternon spp., the mud turtles, and Sternotherus spp., the musk turtles – and Staurotypinae – with Claudius angustatus, the narrow-bridged musk turtle and Staurotypus spp., the Mexican/giant/three-keeled/cross-breasted musk turtles). Staurotypinae may be better as a separate family (Staurotypidae). There are 24+ species.

Musk and mud turtles are also called kinosternids (alluding to the familial name). They are close relatives to Chelydridae, the snapping turtles.

Alternate names	Musk turtles are also known as stinkpots.
Etymology	Musk turtles are capable of releasing a foul-smelling musk from their Rathke’s glands, most similar to those of snapping turtles, under the rear of shells when disturbed. Some species also release foul-smelling secretions from the cloaca.
Physical Appearance	Size: Most are small, reaching 10-15 cm or 3.9-5.9 in SCL. Sternotherus spp. can be the smallest turtles, growing to 8-14 cm (3.1-5.5 in) while Staurotypus spp. can grow to 30 cm (12 in) and have large heads. C. angustatus turtles generally grow to 16.5 cm (6.5 in). Old individuals have especially large heads. Distinguishing features: Have highly domed carapaces with distinct keels down the center. Sexual dimorphism: Females are significantly larger while males have much longer tails. Color: Various, ranging between black, brown, green, and yellowish. Some have a distinctive yellow striping along the sides of the head and neck. Most have no shell markings. Some species have radiating black markings on each carapace scute. Shell: Hindlimbs are mostly invisible when the turtle is at rest. The plastron is hinged in some species (allowing them to wholly enclose their limbs, neck, and tail inside their shells). The carapace is usually solid, lacking the hinges and mobile/flexible zones present in some turtles. Have oblong and moderately domed carapaces. Plastron ranges from reduced to covering the whole shell, with fewer than 10 epidermal marginal scutes. Musk turtles have small and cruciform plastra that give them more efficient leg movement for walking along the bottom of ponds and streams. Staurotypus spp. turtles have plastra of only seven or eight scutes. Genus differences: Mud turtles are generally smaller than musk turtles and do not have as highly domed carapaces. Three-keeled musk turtles have yellow undersides with brown, black, or green bodies and have three distinctive keels that run their length (hence the name). Narrow-bridged musk turtles are typically brown with wood-like scutes (in terms of lines and graining) and often have bright-yellow markings (algae often heavily covers these color markings as they age). They have extremely narrow bridges, such that they can rotate their plastra independently of their carapaces and such broad and narrow heads that they cannot be retracted into the shell. Barbels present on the chins and throats of some Sternotherus species. S. depressus turtles (flattened musk turtles) have relatively wide and flat shells, which may be an adaptation for hiding in crevices along the banks in which they live. Mud turtles lack endoplastra.
Life Cycle	Breed in late spring and early summer. Lay around four hard-shelled eggs (sometimes 1 or 2 huge eggs, sometimes 10 or more tiny eggs). Some species overwinter in subterranean nests (emerging the following spring). Some adults spend winter on land (constructing burrows with small air holes used on warm days). Ranges from female-dominated to male-dominated sexual size dimorphism. Some produce a single clutch in the spring while some nest multiple times in the summer and some nest nearly year-round. Sex determination ranges from genetic with sex chromosomes to temperature-dependent. Embryonic development is direct in some species whereas other species exhibit early embryonic diapause and/or late embryonic estivation. Incubation periods range from 56 to over 366 days.
Ecology, Habitat and Diet	Habitat: Freshwater aquatic systems (slow moving bodies of water, often with soft, muddy bottoms and abundant vegetation). Some species inhabit highly seasonal ephemeral ponds which may only contain water for a few months of each year. Range from north temperate to tropical and rainforest to grasslands to desert. Brumate on land. Can forage on land. Occupy underground retreats/communal nests. Occasionally nest below vegetation. Predators: Racoons eat the eggs of Kinosternon subrubrum (the Eastern/common mud turtle) while herons and alligators often hunt the adults. Diet: Carnivores. Feed mainly on mollusks (snails and clams), crustaceans, insects, annelids, small fish (usually as fresh carrion), and even small carrion. Some are highly specialized mollusk feeders and eat little else. Some also eat algae and the seeds and leaves of certain plants. Grab and crush hard-shelled prey.
Behavior and Locomotion	The yellow mud turtle (Kinosternon flaviscens) is the only species of turtle suspected to exhibit parental care (studies in Nebraska suggest that the females sometimes stay with the nest and may urinate on the eggs long after laying them, either to keep them moist or to protect them from snake predation by making them less palatable). Sternotherus spp. are highly aquatic. However, the common musk turtle is known to bask on fallen trees and coarse woody debris on shorelines. Musk turtles are almost entirely aquatic, spending much of their time walking along the bottom, foraging for food. They are often nocturnal. C. angustatus is a ferocious biter. Some kinosternids can undergo submerged and fully aquatic respiration. Some can estivate underground for up to two years. Locomotion: Capable of limited climbing and will sometimes ascend steep slopes or sloping branches or logs, sometimes falling onto boats from overhanging branches or fallen trees.
Conservation Status and Efforts	Most Kinosternidae species are common, reaching amazing population densities (as high as 1,200 per 2.5 acres [1 ha]). However, two tropical, one subtropical, and one temperate species are listed as Vulnerable on the IUCN Red List. The two tropical species (K. dunni and K. angustipons) are lowland forms with very restricted ranges and hence are probably affected most negatively by habitat destruction. The subtropical species (K. sonoriense) lives primarily in permanent water systems in the deserts of the U.S. Southwest; human competition for water resources has eliminated most of the habitat for this species. K. subrubrum is exploited by the pet trade and listed as an endangered species in Indiana. The temperate species (Sternotherus depressus) also has a restricted distribution in the permanent streams of north-central Alabama; habitat destruction associated with coal mining and forest clear-cutting seems to have caused the declines in this species.
Distribution	Musk turtle: North and South America (Sternotherus spp. in southern Canada, US, and Mexico; Staurotypus spp. in Mexico and Central America, Claudius spp. in Mexico, Guatemala, and Belize) Mud turtle: US, Mexico, Central America, South America (great species richness in Mexico, only three species in South America)
Miscellaneous Information	Sternotherus odoratus (the common musk turtle/stinkpot) is the most common species of Sternotherus in North America. Kinosternids do not have a good fossil record.

Family Emydidae (box, pond, and marsh turtles)

Alternate names	(alternate names)
Etymology	(etymology)
Physical Appearance	(physical appearance)
Life Cycle	(life cycle)
Ecology, Habitat and Diet	(ecology)
Behavior and Locomotion	(behavior)
Conservation Status and Efforts	(conservation status/efforts)
Distribution	(distribution)
Miscellaneous Information	(miscellaneous)

Genus Terrapene (box turtles)

Terrapene belongs to subfamily Emydinae and is comprised of 12 taxa and 4 species (T. carolina, the common box turtle, T. coahuila, the Coahuilan/aquatic box turtle, T. nelsoni, the spotted box turtle, and T. ornata, the western/ornate box turtle). Terrapene was coined by Merrem in 1820 as a genus separate from Emys for those species that had a sternum separated into two or three divisions and that could move these parts independently. The Asian box turtle belongs to a separate genus, Cuora.

Etymology	Terrapene is derived from the Algonquin for turtle. English writers in 1834 referred to them as box-tortoises from their resemblance to tightly closed boxes when the head, tail, and legs are drawn in.
Physical Appearance	Has a domed shell which is hinged at the bottom (allowing it to close its shell tightly to escape predators).
Life Cycle	Chance of death seems not to increase with age after maturity is reached. Average lifespan of 50 years. Significant portion live over 100 years. Growth directly affected by amount of food, type of food, water, illness, et cetera. Age cannot be estimated by counting growth rings on scutes. Eggs are flexible and oblong (on average 2-4 cm or 1-2 in and 5-11 g or 0.2-0.4 oz). Normal clutch size of 1-7 eggs. Average clutch size is larger in more northern populations while southern and captive box turtles have more than one clutch per year. Risk of death is greatest in small individuals due to size and weaker carapace and plastron. Many hatchlings die during their first winter. Adult shells are seldom fractured but still vulnerable to surprise attacks and persistent gnawing/pecking.
Ecology, Habitat and Diet	Habitat: Wide variety (varies on a day-to-day, season-to-season, and species-to-species basis). Generally mesic woodlands (moderate/well-balanced supply of moisture). T. ornata is the only species regularly found in grasslands. The desert box turtle T. o. luteola is found in semideserts (rainfall predominantly in summer). The Coahuilan box turtle T. coahuila is found in a 360 square-km region characterized by marshes, permanent presence of water, and several types of cacti. Predators: Commonly mammals such as minks, skunks, raccoons, dogs, and rodents. Also can be killed by birds (e.g. crows and ravens) and snakes (e.g. racers and cottonmouths). Diet: Omnivores with a varied diet. Basically eat anything they can catch. Mostly invertebrates (e.g. insects, earthworms, and millipedes) as they are plentiful and easy to catch but also 30-90% vegetation. Also eat fruits (e.g. cacti, apples, and several species of berry) and gastropods (e.g. Heliosoma and Succinea). Speculated that for the first 5-6 years they are primarily carnivorous and adults are primarily herbivorous, but there is no scientific basis for such a difference. Box turtles have been reported eating birds and small rodents that were trapped or had already died. Some species will eat poisonous mushrooms on a regular basis, making them poisonous to predators.
Behavior and Locomotion	Defend from predators by hiding, closing the shell, and biting. Tend to move farther into woods prior to hibernation, where they dig a chamber for overwintering. Ornate box turtles dig chambers of up to 50 cm. Eastern box turtles become dormant at a depth of about 10 cm. Location of overwintering can be up to 0.5 km from the summer habitat and is often in close proximity to the previous year's. Active year-round in more southern locations as observed in T. coahuila and T. carolina major. Other box turtles in hotter locations are more active (T. carolina yukatana) or only active during the wet seasons.
Conservation Status and Efforts	T. coahuila is endemic to Coahuila and classified as endangered (range reduced by 40% in past 40-50 years; population reduced from well over 10000 to 2500 in 2002). T. carolina is the most widely distributed and classified as vulnerable. T. ornata is near threatened. T. nelsoni has insufficient information. Efforts and concerns: Sniffer dogs have been trained to find and track box turtles as part of conservation efforts. It is recommended to buy captive bred box turtles (in the regions where this is allowed) to reduce pressure put on wild populations. A 3-year study in Texas found that over 7000 box turtles were taken from the wild for commercial trade and a similar study in Louisiana found that in a 41-month period, nearly 30000 box turtles were taken from the wild for resale, many for export to Europe. Turtles once captured are often kept in poor conditions where up to half of them die. Those living long enough to be sold may suffer from conditions such as malnutrition, dehydration, and infection. Indiana, Tennessee, and other states prohibit collecting wild turtles. Many states require a permit to keep them. Breeding is prohibited in some states for fear of its possible detrimental effects upon wild populations. Box turtles have a low reproduction rate, intensifying the negative impact of collecting box turtles from the wild.
Distribution	The Coahuila box turtle is found only in the Cuatro Ciénegas Basin in Coahuila, Mexico. 800px
Miscellaneous Information	Box turtles do not make good pets for small children. They are easily stressed by over-handling, require more care than generally thought, get stressed when moved into new surroundings, may wander aimlessly until they die trying to find their original home, and can carry Salmonella. The three-toed box turtles (T. carolina triunguis) are often considered the best box turtles to keep as pets since they are hardy and seem to suffer less when moved into a new environment. Box turtles require an outdoor enclosure and consistent exposure to the sun and a varied diet; otherwise, growth can be stunted and the immune system can be injured. Box turtles appeared abruptly in the fossil record (essentially in modern form), which may indicate that they are a generalist species (able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources) as opposed to a specialist species. It is complicated to establish how evolution from other turtles took place. The oldest fossils were found in Nebraska (15 mya in the Miocene) and resemble the aquatic box turtle. T. ornata and T. carolina fossils date from 5 mya. The only recognized extinct subspecies, T. carolina putnami, dates from the Pliocene (5.33-2.58 mya) and had a carapace length of 30 cm (12 in) which is much larger than other species. Box turtles are the official state reptiles of four states (North Carolina and Tennessee honor T. carolina carolina, the eastern box turtle while Missouri honors T. carolina triunguis, the three-toed box turtle, and Kansas honors T. ornata, the ornate box turtle). Pennsylvania almost named the eastern box turtle as the state reptile (passed through one house of legislature).

Genus Actinemys (western pond turtles)

Actinemys belongs to the subfamily Emydinae and has one species, A. marmorata. The taxonomy of the western pond turtle is currently under debate; at present, the IUCN Red List recognises that the western pond turtle belongs in its own genus. However, there is deliberation that it may belong to the genus Emys which is composed of the European pond turtle (E. orbicularis), the Sicilian pond turtle (E. trinacris), and Blanding’s turtle (E. blandingii) which may belong in a separate genus itself (Emydoidea). There were previously thought to be two subspecies of the western pond turtle: the southern western pond turtle (A. m. pallida) and the northern western pond turtle (A. m. marmorata), but now there is evidence for four separate groups, which do not match the distribution of the earlier described subspecies.

Alternate names	Pacific pond turtle, Emys marmorata, Clemmys marmorata
Etymology	The specific name marmorata refers to the marbled pattern of both the soft parts and carapace.
Physical Appearance	Color: The carapace is usually light to dark brown or dull olive, either with no pattern or with an attractive pattern of fine, dark radiating lines on the scutes. The plastron is yellowish, sometimes with dark blotches in the centers of the scutes. The limbs and head are olive, yellow, orange, or brown, often with darker flecks or spots. Size: The shell is 11-21 cm (4.5-8.5 in) in length. The carapace is low and broad, usually widest behind the middle. Adult carapaces are smooth, lacking a keel or serrations. Sexual dimorphism: In males, the cloaca is positioned beyond the edge of the plastron, whereas in females, it does not reach the edge of the plastron. Males have a yellow or whitish chin and throat, a flatter carapace, a more concave plastron, and a more pointed snout than females.
Life Cycle	Thought to live for up to 40 years. May survive more than 50 years in the wild. Hatchlings: Hatchlings from northern California northward overwinter in the nest, which may explain the difficulty researches have had in trying to locate hatchlings in the fall months. Winter rains may be necessary to loosen the hardpan soil where some nests are deposited. It may be that the nest is the safest place for hatchlings to shelter while they await the return of warm weather. Whether it is hatchlings or eggs that overwinter, young first appear in the spring following the year of egg deposition. Western pond turtles develop slowly in areas with short or cool summers, taking up to eight years to reach sexual maturity (may even be 10-12 years). They can grow relatively fast in warmer regions and in some nutrient-rich habitats, where they can reach maturity in half that time. Breeding: Occurs in late spring to mid-summer, with mating taking place under water. Most mature females nest every year, some laying two clutches per season. In early summer the eggs are deposited in the nest, which is generally dug in soil, close to a water source, but some females may dig their nests many meters away from the water's edge (some may move as much as 800 m or half a mile away and up to 90 m or 300 ft above the nearest source of water, but most are within 90 m or 300 ft of water). The female usually leaves the water in the evening and may wander far before selecting a nest site, often in an open area of sand or hardpan that is facing southwards. The nest is flask-shaped with an opening of about 5 cm (2 in). Females spend considerable time covering up the nest with soil and adjacent low vegetation, making it difficult to find unless disturbed. The female lays an average of 4-7 eggs (range 1-13) per clutch, which hatch after ~13-17 weeks.
Ecology, Habitat and Diet	Habitat: Occur in both permanent and intermittent waters, including marshes, streams, rivers, ponds, and lakes. Favor habitats with large numbers of emergent logs or boulders, where they aggregate to bask. Also bask on top of aquatic vegetation or position. Often overlooked in the wild. Terrestrial habitats are also extremely important since many intermittent ponds can dry up during summer and fall months along the west coast, especially during times of drought. Can spend upwards of 200 days out of water. Have been found more than 1 km away from water. Many overwinter outside of the water, often creating their nest for the year. Predators: Generally well protected due to hard shell. Several predators threaten A. marmorata, especially hatchlings due to their small size and soft shell. Raccoons, otters, ospreys, and coyotes and the biggest natural threats, and hatchlings have the additional threats of weasels, bullfrogs, and large fish. Diet: Omnivorous. Most of their animal diet includes insects (aquatic insects and larvae), crayfish, and other aquatic invertebrates. Small fish, tadpoles, and frogs are eaten occasionally, and carrion is eaten when available. Plant foods include filamentous algae, lily pads, tule, and cattail roots.
Behavior and Locomotion	Possible to observe resident turtles by moving slowly and hiding behind shrubs and trees. Can be encouraged to use artificial basking substrate (rafts) which allows for easy detection of the species in complex habitats. Bask on mats of floating vegetation, floating logs, or on mud banks just above the water's surface. Engage in aquatic basking in warmer climates by moving into the warm thermal environment in or on top of submerged mats of vegetation.
Conservation Status and Efforts	Extirpated in Canada (May 2002: Canadian Species at Risk Act). Vulnerable on the IUCN Red List due to habitat destruction (ponds, wetlands, contamination of other water sources), conversion of wetlands to farmlands, water diversions, and urbanization. Listed as endangered in Washington State and protected in Oregon and California. Pet trade has declined over recent years for this turtle. Occasional losses from illegal collection for food by immigrant populations from Asia. Mortality from motor vehicle collisions. Predation from introduced species (e.g. bullfrogs). Efforts: Commercial harvest or take of western pond turtles has been prohibited in all U.S. states where it is found since the 1980s. The recent increase in stock ponds and other man-made water sources appears to have a positive impact on population numbers and a few "head-start" programs (where the young are raised in captivity until their shells begin to harden and they are less susceptible to predation) claim to have had excellent survivorship rates after being released into the wild. However, re-introduction is limited if the habitat of the species is not protected.
Distribution	Originally ranged from northern Baja California, Mexico north to the Puget Sound region of Washington. As of 2007, they have become rare or absent in the Puget Sound area. They have a disjunct distribution in most of the Northwest, and some isolated populations exist in southern Washington. Pond Turtles are now rare in the Willamette Valley north of Eugene, Oregon, but abundance increases south of that city where temperatures are higher. They may be locally common in some streams, rivers and ponds in southern Oregon. A few records are reported east of the Cascade Mountains, but these may have been based on introduced individuals. They range up to 305 m (1,001 ft) in Washington, and to about 915 m (3,002 ft) in Oregon (sea level to 1500 m). They also occur in Uvas Canyon area, Santa Cruz Mts, California, and in the North Bay, and lakes such as Fountaingrove Lake.

Genus Malaclemys (diamondback terrapins)

Malaclemys belongs to the subfamily Deirochelyinae and has one species, M. terrapin, which has seven subspecies. The Bermuda population has not been assigned a subspecies.

Etymology	Terrapin from the Algonquin word for turtle (torope). Diamond pattern on carapace.
Physical Appearance	Shell: Overall pattern and coloration vary greatly. Usually wider at the back than in the front (appears wedge-shaped from above). Color: Shell can vary from brown to grey (greyish to nearly blackish carapace). Body can be grey, brown, yellow, or white. All have a unique pattern of wiggly, black markings or spots on their body and head. One of the darkest species of turtle. Size: Greatest sexually dimorphic size disparity found in any North American turtle. Males grow to approximately 13 cm (5.1 in) while females grow to an average of around 19 cm (7.5 in). Largest female on record was just over 23 cm (9.1 in). Specimens from regions that are consistently warmer in temperature tend to be larger than those from cooler areas in the north. Males weigh 300 g (11 oz) on average while females weigh around 500 g (18 oz). Largest females can weigh up to 1000 g (35 oz). Distinguishing features: Tuberculate (knobbed keel). Higher shell with a deeper bridge. Deeper gular notch. Consistently white upper lip. Uniformly colored carapace and plastron. Skull with a long and bony temporal arch. Adaptations to environment: Can survive in varying salinities. Skin is largely impermeable to salt. Have lachrymal salt glands not present in their relatives which are used primarily when the turtle is dehydrated. Can distinguish between drinking water of different salinities. Exhibit unusual and sophisticated behaviors to obtain fresh water, such as drinking the freshwater surface layer that can accumulate on top of saltwater during rainfall and raising their heads into the air with mouths open to catch falling rain drops. Strong swimmers. Large and strongly webbed hind feet but not flippers as sea turtles have. Strong jaws for crushing shells of prey (e.g. clams and snails) like their relatives Graptemys. Females have larger and more muscular jaws than males.
Life Cycle	Eggs: Clutches of 4-22 (usually not more than 4-8). Clutch sizes vary latitudinally with average clutch sizes as low as 5.8 eggs/clutch in southern Florida to 10.9 in New York. Are 1-inch long, pinkish-white, oval-shaped, and covered with leathery shells. Hatch in late summer or early fall. Usually hatch in 60-85 days, depending on the temperature and the depth of the nest. Favor females (almost six to one). Hatchlings: Usually emerge from the nest in August and September but may overwinter in the nest after hatching. Sometimes stay on land in the nesting areas in both fall and spring and may remain terrestrial for much or all of the winter in some places. Freeze tolerant, which may facilitate overwintering on land. Hatchlings have lower salt tolerance than adults (one- and two-year-old terrapins use different habitats than old individuals use). 1-1.5 in long. May spend their first years upstream in creeks. Move back down to nutrient-rish salt marshes as they grow older where there are plenty of nesting sites. Growth: Growth rates, age of maturity, and maximum age are not well known for terrapins in the wild. Males reach sexual maturity before females due to their smaller adult size. Sexual maturity is dependent on size rather than age (in females at least). Estimations of age based on counts of growth rings on the shell are as of yet untested so it is unclear how to determine the ages of wild terrapins. Maturity in males is reached in 2-3 years at around 4.5 inches (110 mm) in length while maturity in females is reached in 6-7 years (8-10 years for northern populations) at around 6.75 inches (171 mm). Mating: Occurs in early spring. Able to produce eggs for several years after a single mating. Courtship has been seen in May and June and is similar to that of the closely related red-eared slider (Trachemys scripta). Females can mate with multiple males and store sperm for years, resulting in some clutches of eggs with more than one father. Temperature dependent sex determination. Females can lay up to three clutches of eggs per year in the wild and up to five clutches per year in captivity. Unknown how often they may skip reproduction so true clutch frequency is unknown. Females may wander considerable distances on land before nesting. Nests are usually laid in sand dunes or scrub vegetation near the ocean in June and July, but nesting may start as early as late April in Florida. Females dig a nest cavity 4-8 inches deep and will quickly abandon a nest attempt if they are disturbed while nesting. Quickly return to the ocean after covering the nest and do not return except to nest again.
Ecology, Habitat and Diet	Habitat: Brackish coastal tidal marshes. Spartina (cordgrass) marshes that are flooded at high tide. Also Floridian mangrove swamps. Favor reedy marshes. Can survive in freshwater as well as full-strength ocean water but adults prefer intermediate salinities. Unclear why terrapins do inhabit the upper reaches of rivers within their range, as they tolerate freshwater in captivity. They are possibly limited by distribution of their prey. Live close to shore unlike sea turtles and require freshwater for drinking purposes. Predators: Nests, hatchlings, and sometimes adults are eaten by raccoons, foxes, rats, and many species of birds, especially crows and gulls. Diet: No competition from other turtles, though snapping turtles do occasionally make use of salt marshes. May eat enough organisms at high densities to have ecosystem-level effects, specially since periwinkle snails have a tendency to overgraze important marsh plants. Diet is not well studied. Data comes from southeastern end of range. Eat shrimp, clams, crabs, mussels, and other marine invertebrates (especially periwinkle snails). Also eat fish, insects, and carrion. Will only eat soft-shelled mollusks and crustaceans because they use the ridges in their jaws to crush prey.
Behavior and Locomotion	Tend to live in the same areas for most or all of their lives. Do not make long distance migrations. Many aspects are poorly known because nesting is the only activity that occurs on land. Limited data suggest that terrapins become dormant in the colder months in most of their range in the mud of creeks and marshes. Quick to flee and difficult to observe in the wild. May be possible to observe them basking on or walking between oyster beds and mudflats. Mild-mannered. Excellent swimmers and will head for water if approached. Known to recognize habits in captivity and learn quickly what times people are normally around. Seem very sociable except when their cage is too small. Enjoy basking together (often one on top of the other).
Conservation Status and Efforts	In the 1900s the species was once considered a delicacy to eat and was hunted almost to extinction. The numbers also decreased due to the development of coastal areas and, more recently, wounds from the propellers on motorboats. Another common cause of death is the trapping of the turtles under crabbing and lobster nets. 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, Alabama, Louisiana, North Carolina, and Virginia. The diamondback terrapin is listed as a “high priority species” under the South Carolina Wildlife Action Plan. In New Jersey, it was recommended to be listed as a species of Special Concern in 2001. In July 2016, the species was removed from the New Jersey game list and is now listed as non-game with no hunting season. In Connecticut there is no open hunting season for this animal. However, it holds no federal conservation status. The species is classified as Near Threatened by the IUCN due to decreasing population numbers in much of its range. Threats: The major threats to diamondback terrapins are all associated with humans and probably differ in different parts of their range. People tend to build their cities on ocean coasts near the mouths of large rivers and in doing so they have destroyed many of the huge marshes terrapins inhabited. Nationwide, probably >75% of the salt marshes where terrapins lived have been destroyed or altered. Currently, ocean level rise threatens the remainder. Traps used to catch crabs both commercially and privately have commonly caught and drowned many diamondback terrapins, which can result in male-biased populations and local population declines and even extinctions. When these traps are lost or abandoned (“ghost traps”), they can kill terrapins for many years. Density of predators are often increased because of their association with humans. Predation rates can be extremely high; predation by raccoons on terrapin nests at Jamaica Bay Wildlife Refuge in New York varied from 92-100% each year from 1998–2008. Terrapins are killed by cars when nesting females cross roads, and mortality can be high enough to seriously impact populations. Terrapins are still harvested for food in some states. Terrapins may be affected (suffocated?) by pollutants such as metals and organic compounds, but this has not been demonstrated in wild populations. Hatchlings can get trapped in tire tracks left by vehicles on the beach, get dehydrated, and die before reaching water. There is an active casual and professional pet trade in terrapins and it is unknown how many are removed from the wild for this purpose. Some people breed the species in captivity and some color variants are considered especially desirable. In Europe, Malaclemys are widely kept as pets, as are many closely related species. Efforts: The Diamondback Terrapin Working Group deals with regional protection issues. There is no national protection except through the Lacey Act, and little international protection. Diamondback terrapins are the only U.S. turtles that inhabit the brackish waters of estuaries, tidal creeks and salt marshes. With a historic range stretching from Massachusetts to Texas, terrapin populations have been severely depleted by land development and other human impacts along the Atlantic coast. Terrapin-excluding devices are available to retrofit crab traps; these reduce the number of terrapins captured while having little or no impact on crab capture rates. In some states (NJ, DE, MD), these devices are required by law. Relationship with humans: In Maryland, diamondback terrapins were so plentiful in the 18th century that slaves protested the excessive use of this food source as their main protein. Late in the 19th century, 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 City 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, over capture was so high by 1920, the harvest of terrapins reached only 823 pounds for the year. According to the FAA National Wildlife Strike Database, a total of 18 strikes between diamondback terrapins and civil aircraft were reported in the US from 1990 to 2007, none of which caused damage to the aircraft. On July 8, 2009, flights at John F. Kennedy Airport in New York City were delayed for up to one and a half hours as 78 diamondback terrapins had invaded one of the runways. The turtles, which according to airport authorities were believed to have entered the runway in order to nest, were removed and released back into the wild. A similar incident happened on June 29, 2011, when over 150 turtles crossed runway four, closing the runway and disrupting air traffic. Those terrapins were also relocated safely. The Port Authority of New York and New Jersey installed a turtle barrier along runway 4L at JFK to reduce the number of terrapins on the runway and encourage them to nest elsewhere. Nevertheless, on June 26, 2014, 86 terrapins made it onto the same runway, as a high tide carried them over the barrier. Their population is controlled by the raccoon population; it has been shown that as the raccoons decrease in number, mating terrapins increase, leading to increased turtle activity at the airport. Diamondback terrapins were heavily harvested for food in colonial America and probably before that by Native Americans. Terrapins were so abundant and easily obtained that slaves and even the Continental Army ate large numbers of them. By 1917, terrapins had become a fashionable delicacy and sold for as much as $5 each. Huge numbers of terrapins were harvested from marshes and marketed in cities. By the early 1900s populations in the northern part of the range were severely depleted and the southern part was greatly reduced as well. As early as 1902 the U.S. Bureau of Fisheries (which later became the U.S. Fish and Wildlife Service) recognized that terrapin populations were declining and started building large research facilities, centered at the Beaufort, North Carolina Fisheries Laboratory, to investigate methods for captive breeding terrapins for food. People tried (unsuccessfully) to establish them in many other locations, including San Francisco.
Distribution	The very narrow strip of coastal habitats on the Atlantic and Gulf coasts of the United States, from as far north as Cape Cod, Massachusetts to the southern tip of Florida and around the Gulf Coast to Texas. A population of terrapins on Bermuda has been determined to be self-established (not introduced by humans).
Miscellaneous Information	Maryland named the diamondback terrapin its official state reptile in 1994. The University of Maryland, College Park has used the species as its nickname (the Maryland Terrapins) and mascot (Testudo) since 1933, and the school newspaper has been named The Diamondback since 1921. The athletic teams are often referred to as "Terps" for short. The terrapin has also been a symbol of the Grateful Dead because of their song "Terrapin Station". Many images of the terrapin dancing with a tambourine appear on posters, T-shirts and other places in Grateful Dead memorabilia.

Genus Graptemys (map turtles)

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Genus Trachemys (sliders)

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Genus Chrysemys (painted turtles)

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Genus Pseudemys (cooters and redbellies)

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Genus Clemmys (spotted turtle)

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Genus Glyptemys (Sculptured Turtles-wood and bog turtle)

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Genus Deirochelys (chicken turtle)

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Genus Emydoidea (Blanding’s turtle)

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Family Testudinidae (tortoises)

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Family Cheloniidae (sea turtles)

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Family Trionychidae (soft shelled turtles)

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