# 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, containing 2 species, encompassing gharials and false gharials;
• Crocodylidae, containing 14 species in 3 genera, encompassing crocodiles; and
• Alligatoridae, containing 7 species in 4 genera, encompassing alligators and caimans.
Etymology Latinizing of the Greek κροκόδειλος (crocodeilos), which means both lizard and Nile crocodile. Crocodylia, as coined by Wermuth, in regards to the genus Crocodylus appears to be derived from the ancient Greek κρόκη (kroke)—meaning shingle or pebble—and δρîλος or δρεîλος (dr(e)ilos) for "worm". The name may refer to the animal's habit of basking on the pebbled shores of the Nile. Crocodilians range in size from the Paleosuchus and Osteolaemus species, which reach 1–1.5 m (3 ft 3 in–4 ft 11 in), to the saltwater crocodile, which reaches 7 m (23 ft) and weighs up to 2,000 kg (4,400 lb), though some prehistoric species such as the late Cretaceous Deinosuchus were even larger at up to about 11 m (36 ft) and 3,450 kg (7,610 lb). They tend to be sexually dimorphic, with males much larger than females. Though there is diversity in snout and tooth shape, all crocodilian species have essentially the same body morphology. They have solidly built, lizard-like bodies with elongated, flattened snouts and laterally compressed tails. Their limbs are reduced in size; the front feet have five digits with little or no webbing, and the hind feet have four webbed digits and a rudimentary fifth. The skeleton is somewhat typical of tetrapods, although the skull, pelvis and ribs are specialised; in particular, the cartilaginous processes of the ribs allow the thorax to collapse during diving and the structure of the pelvis can accommodate large masses of food, or more air in the lungs. Both sexes have a cloaca, a single chamber and outlet at the base of the tail into which the intestinal, urinary and genital tracts open. It houses the penis in males and the clitoris in females. The crocodilian penis is permanently erect and relies on cloacal muscles for eversion and elastic ligaments and a tendon for recoil. The testes or ovaries are located near the kidneys. The eyes, ears and nostrils of crocodilians are at the top of the head. This allows them to stalk their prey with most of their bodies underwater. Crocodilians possess a tapetum lucidum which enhances vision in low light. While eyesight is fairly good in air, it is significantly weakened underwater. The fovea in other vertebrates is usually circular, but in crocodiles it is a horizontal bar of tightly packed receptors across the middle of the retina. When the animal completely submerges, the nictitating membranes cover its eyes. In addition, glands on the nictitating membrane secrete a salty lubricant that keeps the eye clean. When a crocodilian leaves the water and dries off, this substance is visible as "tears". The ears are adapted for hearing both in air and underwater, and the eardrums are protected by flaps that can be opened or closed by muscles. Crocodilians have a wide hearing range, with sensitivity comparable to most birds and many mammals. They have only one olfactory chamber and the vomeronasal organ is absent in the adults indicating all olfactory perception is limited to the olfactory system. Behavioural and olfactometer experiments indicate that crocodiles detect both air-borne and water-soluble chemicals and use their olfactory system for hunting. When above water, crocodiles enhance their ability to detect volatile odorants by gular pumping, a rhythmic movement of the floor of the pharynx. The well-developed trigeminal nerve allows them to detect vibrations in the water (such as those made by potential prey). The tongue cannot move freely but is held in place by a folded membrane. While the brain of a crocodilian is fairly small, it is capable of greater learning than most reptiles. Though they lack the vocal folds of mammals and the syrinx of birds, crocodilians can produce vocalisations by vibrating three flaps in the larynx. Habitat: Amphibious. Predators: Tend to be at the top of the food chain. Diet: Largely carnivorous. Locomotion: Crocodilians are excellent swimmers. During aquatic locomotion, the muscular tail undulates from side to side to drive the animal through the water while the limbs are held close to the body to reduce drag. When the animal needs to stop, steer, or manoeuvre in a different direction, the limbs are splayed out. Crocodilians generally cruise slowly on the surface or underwater with gentle sinuous movements of the tail, but when pursued or when chasing prey they can move rapidly. Crocodilians are less well-adapted for moving on land, and are unusual among vertebrates in having two different means of terrestrial locomotion: the "high walk" and the "low walk". Their ankle joints flex in a different way from those of other reptiles, a feature they share with some early archosaurs. One of the upper row of ankle bones, the astragalus, moves with the tibia and fibula. The other, the calcaneum, is functionally part of the foot, and has a socket into which a peg from the astragalus fits. The result is that the legs can be held almost vertically beneath the body when on land, and the foot can swivel during locomotion with a twisting movement at the ankle. Crocodilians, like this American alligator, can "high walk" with the limbs held almost vertically, unlike other reptiles. The high walk of crocodilians, with the belly and most of the tail being held off the ground, is unique among living reptiles. It somewhat resembles the walk of a mammal, with the same sequence of limb movements: left fore, right hind, right fore, left hind. The low walk is similar to the high walk, but without the body being raised, and is quite different from the sprawling walk of salamanders and lizards. The animal can change from one walk to the other instantaneously, but the high walk is the usual means of locomotion on land. The animal may push its body up and use this form immediately, or may take one or two strides of low walk before raising the body higher. Unlike most other land vertebrates, when crocodilians increase their pace of travel they increase the speed at which the lower half of each limb (rather than the whole leg) swings forward; by this means, stride length increases while stride duration decreases. Though typically slow on land, crocodilians can produce brief bursts of speed, and some can run at 12 to 14 km/h (7.5 to 8.7 mph) for short distances. A fast entry into water from a muddy bank can be effected by plunging to the ground, twisting the body from side to side and splaying out the limbs. In some small species such as the freshwater crocodile, a running gait can progress to a bounding gallop. This involves the hind limbs launching the body forward and the fore limbs subsequently taking the weight. Next, the hind limbs swing forward as the spine flexes dorso-ventrally, and this sequence of movements is repeated. During terrestrial locomotion, a crocodilian can keep its back and tail straight, since the scales are attached to the vertebrae by muscles. Whether on land or in water, crocodilians can jump or leap by pressing their tails and hind limbs against the substrate and then launching themselves into the air.

### Family Crocodylidae (crocodiles)

Picture(s)
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: Range from 1.5-1.9 m (dwarf crocodiles) to over 7 m and 1000 kg (saltwater crocodiles).

Eating: Have 80 teeth 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.

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).

Picture(s)
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

### 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).

Picture(s)
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.

Picture(s) Musk turtles are also known as stinkpots. 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. 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. 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. 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. 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. 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. 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) 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)

#### 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.

Picture(s) 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. Has a domed shell which is hinged at the bottom (allowing it to close its shell tightly to escape predators). 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. 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. 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. 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. The Coahuila box turtle is found only in the Cuatro Ciénegas Basin in Coahuila, Mexico. 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.

#### 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.

Picture(s) Terrapin from the Algonquin word for turtle (torope). Diamond pattern on carapace. 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. 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. 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. 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). 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. 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). 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)

Graptemys belongs to the subfamily Deirochelyinae and comprises 13 species and 15 taxa.

#### Genus Trachemys (sliders)

Trachemys belongs to subfamily Deirochelyinae. The most famous type of slider is the red-eared slider, T. scripta elegans, a subspecies of the pond slider. Thus, the information below will be for the red-eared slider.

Picture(s) Red-eared sliders are also known as red-eared terrapins. Small red stripes behind eyes, has an ability to slide off rocks and logs and into the water quickly, previously known as Troost’s turtle for Dutch-American herpetologist Gerard Troost Size: Carapace can reach more than 40 cm (16 in), but the average length ranges from 15-20 cm (6-8 in). Sexual dimorphism: Females are usually larger than males. Red-eared slider young look practically identical regardless of their sex. The shells of mature males are smaller than those of females and the red marks fade with age. Male red-eared sliders reach sexual maturity when their carapaces' diameters measure 10 cm (3.9 in) and females reach maturity when their carapaces measure 15 cm (6 in). Both male and females reach sexual maturity at five to six years. Males have longer claws on their front feet than the females which help them to hold on to a female during mating and is used during courtship displays. The male's tail is thicker and longer as it contains their dark coloured and retractable reproductive organ. The cloacal opening of the female is usually at or under the rear edge of the carapace while the male's opening occurs beyond the edge of the carapace. Males’ plastra are slightly concave, which helps to stabilize the male on the female’s carapace during mating, while females’ plastra are completely flat. Older males can sometimes have a dark greyish-olive green melanistic coloration with very subdued markings (red stripe may be difficult to see or absent). Females’ appearances are substantially the same throughout life. Poikilotherms: Need to sunbathe frequently to warm themselves and maintain their body temperatures. Shell: The upper carapace consists of: the vertebral scutes which form the central, elevated portion, the pleural scutes which are located around the vertebral scutes, and the marginal scutes which are around the edge of the carapace. The rear marginal scutes are notched. The scutes are bony keratinous elements. The carapace is oval and flattened (especially in the male) and has a weak keel that is more pronounced in the young. The color of the carapace changes depending on the age of the turtle. The plastron is spotted, in contrast to that of a painted turtle. Color: The carapace usually has a dark green background with light and dark, highly variable markings. In young or recently hatched turtles, it is leaf green and gets slightly darker as a turtle gets older, until it is a very dark green, and then turns a shade between brown and olive green. The plastron is always a light yellow with dark, paired, irregular markings in the centre of most scutes. The plastron is highly variable in pattern. The head, legs, and tail are green with fine, irregular, yellow lines. The whole shell is covered in these stripes and markings that aid in camouflaging an individual. Distinguishing features: Red stripe on each side of the head, which may lose color over time. Some individuals can also have a small mark of the same color on the top of their heads. Red-eared sliders do not have visible outer ears or external auditory canal: instead, they rely on middle ears entirely covered by cartilaginous tympanic discs. Typically live 20-30 years though some have lived for more than 40 years. Shorter life expectancy when kept in captivity. Quality of their living environment has a strong influence on their lifespans and well being. Eggs: Incubation takes 59 to 112 days. Late-season hatchlings may spend the winter in the nest and emerge when the weather warms in the spring. Just prior to hatching, the egg contains 50% turtle and 50% egg sac. A new hatchling breaks open its egg with its egg tooth, which falls out about an hour after hatching. This egg tooth never grows back. Hatchlings may stay inside their eggshells after hatching for the first day or two. If they are forced to leave the eggshell before they are ready, they will return if possible. When a hatchling decides to leave the shell, it still has a small sac protruding from its plastron. The yolk sac is vital and provides nourishment while visible, and several days later it will have been absorbed into the turtle's belly. The sac must be absorbed, and does not fall off. The split must heal on its own before the turtle is able to swim. The time between the egg hatching and water entry is 21 days. Damage to or inordinate motion of the protruding egg yolk, enough to allow air into the turtle's body, results in death. This is the main reason for marking the top of turtle eggs if their relocation is required for any reason. An egg turned upside down will eventually terminate the embryo's growth by the sac smothering the embryo. If it manages to reach term, the turtle will try to flip over with the yolk sac, which would allow air into the body cavity and cause death. The other fatal danger is water getting into the body cavity before the sac is absorbed completely and while the opening has not completely healed yet. The sex of red-eared sliders is determined by the incubation temperature during critical phases of the embryos' development. Only males are produced when eggs are incubated at temperatures of 22–27 °C (72–81 °F), whereas females develop at warmer temperatures. Colder temperatures result in the death of the embryos. Breeding: Usually occurs between March and July. Takes place underwater. Courtship: The male swims around the female and flutters or vibrates the back side of his long claws on and around her face and head (possibly to direct pheromones towards her). The female swims toward the male and (if she is receptive) sinks to the bottom for mating. Female may become aggressive towards the male if not receptive. Courtship can last 45 minutes but mating takes only 10 minutes. A male may appear to on occasion be courting another male and when kept in captivity may also show this behaviour towards other household pets, which could be a sign of dominance and may preclude a fight. Young turtles may carry out the courtship dance before they reach sexual maturity at five years of age (but they are unable to mate). Egg laying: Females spend extra time basking after mating to keep her eggs warm and may also have changes of diet (eating only certain foods or not eating as much as they normally would). Females can lay between two and 30 eggs depending on body size and other factors. Females can lay up to five clutches in the same year. Clutches are usually spaced 12 to 36 days apart. Time between mating and egg-laying can be days or weeks. Actual egg fertilization takes place during the egg-laying which also permits the laying of fertile eggs the following season (as the sperm can remain viable and available in the female's body in the absence of mating). Females spend less time in the water in the weeks before egg laying. A female smells and scratches at the ground (indicating she is searching for a suitable place to lay her eggs), excavates a hole using her hind legs, and lays her eggs in it. Habitat: Inhabit areas with a source of still, warm water, such as ponds, lakes, swamps, creeks, streams, or slow-flowing rivers. Live in areas of calm water where they are able to leave the water easily by climbing onto rocks or tree trunks so they can warm up in the sun. Often found sunbathing in a group or even on top of each other. Also require abundant aquatic plants (as these are the adults' main food, although they are omnivores). Always remain close to water unless they are searching for a new habitat or when females leave the water to lay their eggs. As an invasive species: Invasive red-eared sliders cause negative impacts in ecosystems. They have advantages over natives, including a lower age at maturity, higher fecundity or fertility rates, and a larger body size which gives them a competitive advantage at basking and nesting sites. They exploit food resources, transmit diseases and parasites, produce more offspring, are more aggressive and out-compete in food and nesting and basking sites), displace other turtle species, and eat plants as well as animals, so they could also have a negative impact on a range of native aquatic species (including rare frogs). A malaria-like parasite was spread to two wild turtle populations in Lane Cove River, Sydney. Diet: Omnivorous Almost entirely aquatic. Leave water to sunbathe. Dormancy: Occasionally rise to the surface for food or air, can occur to varying degrees. Usually become dormant over the winter at the bottoms of ponds or shallow lakes but have also been found under banks and rocks and in hollow stumps. Generally become inactive in October (when temperatures fall below 10 °C or 50 °F). Enter a state of sopor (do not eat or defecate, remain nearly motionless, frequency of their breathing falls). Can become active in warmer winter climates and come to the surface for basking. Quickly return to dormant state when the temperature begins to drop again. Generally come up for food in early March to as late as the end of April. Can survive anaerobically for weeks (producing ATP from glycolysis). Metabolic rate drops dramatically with heart rate and cardiac output dropping by 80% to minimise energy requirements. Lactic acid produced is buffered by minerals in the shell, which prevents acidosis. Red-eared sliders kept captive indoors should not undergo dormancy. On IUCN’s list of the 100 most invasive species (invasive in eastern Australia). Invasive species: Red-eared sliders have been released or escaped into the wild in many parts of the world because of their popularity as a pet. Feral populations are now found in Australia, Europe, South Africa, the Caribbean Islands, Israel, Bahrain, the Mariana Islands, Guam, and southeast and far-east Asia. In Australia, it is illegal for members of the public to import, keep, trade, or release red-eared sliders, as they are regarded as an invasive species. Their import has been banned by the EU as well as specific EU member countries. In 2015 Japan announced it was planning to ban the import of red-eared sliders, but it would probably not take effect until 2020. In Australia, breeding populations have been found in New South Wales and Queensland, and individual turtles have been found in the wild in Victoria, the Australian Capital Territory and Western Australia. The Queensland government has invested close to $1 million AUD in eradication programs to date. There have been varying degrees of action by state governments to date, from ongoing eradication efforts by the Queensland government to very little action by the government of New South Wales. Experts have ranked the species as high priority for management in Australia and are calling for a national prevention and eradication strategy, including a concerted education and compliance program to stop the illegal trade, possession and release of slider turtles. Some states have other laws and regulations regarding possession of red-eared sliders because they can be an invasive species where they are not native and have been introduced through the pet trade. Now, it is illegal in Florida to sell any wild-type red-eared slider, as they interbreed with the local yellow-bellied slider population (T. s. scripta). Unusual color varieties such as albino and pastel red-eared sliders (from captive breeding) can still be sold. As a pet: World’s most commonly traded reptile (relatively low price, small size, easy maintenance). As with other turtles, tortoises, and box turtles, individuals that survive their first year or two live generally around 30 years. Infection risk. Can inflict painful bites when mature. Many are dumped into the wild when mature with negative ecological, social and economic impacts. As a Salmonella carrier: The turtle may also have significant public health costs due to the impacts of turtle-associated salmonella on human health. Outbreaks in multiple states and fatalities in children, associated with handling salmonella-infected turtles, have been recorded in the USA. Salmonella can also spread to humans when turtles contaminate drinking water. They are asymptomatic carriers of Salmonella. This has given rise to justifiable concerns given the many instances of infection of humans caused by the handling of turtles, which has led to restrictions in the sale of red-eared sliders in the USA. A 1975 (FDA) regulation bans the sale of both turtle eggs and turtles with a carapace length of less than 4 in (10 cm) except "for bona fide scientific, educational, or exhibition purposes, other than use as pets." This regulation comes under the Public Health Service Act, and is enforced by the FDA in cooperation with state and local health jurisdictions. Turtles and turtle eggs found to be offered for sale in violation of this provision are subject to destruction in accordance with FDA procedures. A fine of up to$1,001 and/or imprisonment for up to one year is the penalty for those who refuse to comply with a valid final demand for destruction of such turtles or their eggs. Wash hands immediately after playing with the turtle, feeding it, or changing its water. United States to northern Argentina, originated from the area around the Mississippi River and the Gulf of Mexico in warm climates in the southeastern United States, native areas range from the southeast of Colorado to Virginia and Florida Haugrud’s slider turtle, T. haugrudi, is extinct. The Teenage Mutant Ninja Turtles were revealed as red-eared slider turtles in the second volume of the Tales of the Teenage Mutant Ninja Turtles which led to a pet craze in Great Britain and subsequent ecological havoc as they were accidentally or deliberately released in the wild

#### Genus Chrysemys (painted turtles)

Chrysemys belongs to the subfamily Deirochelyinae and is a monotypic genus, with C. picta as its only species. It has four subspecies, C. p. picta (eastern), C. p. marginata (midland), C. p. dorsalis (southern), and C. p. bellii (western), which intergrade, or blend together, at range boundaries.

#### Genus Pseudemys (cooters and redbellies)

Pseudemys belongs to the subfamily Deirochelyinae, and there are seven species, some of which the validity remains in question:

• P. alabamensis, the Alabama red-bellied cooter;
• P. concinna, the river cooter, split up into the subspecies
• P. c. concinna, the Eastern river cooter,
• P. c. floridiana, the coastal plain/Florida cooter, and
• P. c. suwanniensis, the Suwannee cooter;
• P. gorzugi, the Rio Grande cooter;
• P. nelsoni, the Florida red-bellied cooter;
• P. peninsularis, the peninsula cooter;
• P. rubriventris, the northern red-bellied cooter; and
• P. texana, the Texas river cooter.
Picture(s)
Etymology Cooters from kuta (the word for turtle in Bambara and Malinké), brought to America by African slaves. The specific name gorzugi is in honor of George R. Zug, Curator of Amphibians and Reptiles, National Museum of Natural History. The specific name nelsoni is in honor of American biologist George Nelson (born 1873).
Physical Appearance Among the largest of the family Emydidae, with carapaces up to 44 cm (17.3 in) and weighing up to 10 kg (22 lb).

Species Info
P. alabamensis A mature female can be 14 inches, while a mature male can be 12 inches. Plastron color ranges from pale yellow to dark red but is most often orange to light red. Carapace may be greenish to dark brown or black with red, orange, or yellow markings along the sides. The marking and coloration are typically more intense in younger specimens. Yellowish stripes decorate its legs, neck, and head. A unique feature of the species is the notch at the tip of the turtle’s upper jaw. This indentation has a cusp on either side of it, and toothlike projections on the lower jaw fit into these cusps. As with many water turtles, males have elongated claws on their front feet for mating rituals.
P. concinna The river cooter is a fairly large turtle (up to 12 inches) often observed basking on rocks and logs along the banks or in rivers. The carapace is green or olive to dark brown. It is slightly flared posteriorly and often highlighted with an intricate reticulated pattern of lighter yellowish markings, which may be thinner or absent in older individuals. On the river cooter, a light, backward-facing C-shaped mark on the second scute on each side of the carapace can be used to distinguish it from the Florida cooter turtle. The underside of some marginals are marked by doughnut-shaped dark spots with light centers. The plastron and bridge have dark markings, particularly along the seams between scutes. The head and neck have numerous yellow "hairpin" stripes. The postorbital stripe is not as broad as in the slider turtle, with which it might be confused. Males have straight, elongated foreclaws. Each scute along the margin of the river cooter’s carapace has a wide, yellow bar running down the centre, while the lower parts of each of these scutes are patterned with blotches or rings. The plastron is yellow to orange and may occasionally be marked with a black pattern which fades with age. The neck, limbs and tail of the river cooter are olive to brown or black with cream, yellow or orange stripes noticeable on the head, chin and legs. Wide yellow stripes can be seen on the underside of the neck, with the most central stripe branching to form a Y-shaped mark. The adult female river cooter tends to have a higher, more domed carapace than the male. Hatchlings of this species differ from the adults in being more brightly coloured with a greener shell, brighter markings and a keel running down the centre of the carapace.
P. gorzugi Up to 37.2 cm (14.5 in) in carapace length. Males only reach 25 cm. The elongated and flattened carapace is slightly keeled and has serrated posterior scutes is olive to greenish brown with Mature males have elongated claws used for courtship. The carapace (upper shell) is elongated, oval, and flattened, with a slight mid-line keel and serrated rear margin. The scutes along the midline of the carapace are broader than long, although the first one behind the marginal scutes may be slightly elongated. Carapace color is olive to greenish brown with a pattern of blotches of alternating yellow and black rings on each scute. The plastron (lower shell) is narrow, hingeless, and has a notch at the rear margin; color is yellow with black seam borders in juveniles, but the dark borders fade with maturity. The upper jaw is smooth (not notched or toothed). The skin is green with yellow stripes on the head, neck, limbs and tail. Behind each eye is an oval, dark-bordered yellow blotch. Males have long, thin foreclaws and a thick tail; the vent is posterior to the rear margin of the carapace. Females have a taller carapace, and the vent is beneath the rear margin of the carapace. Differs from Chrysemys picta in lacking an ornately marked plastron (lower shell). Differs from Pseudemys texana in lacking a median notch often flanked by toothlike cusps on the upper jaw, and by lacking a red-tinged rim on the plastron. It differs from Trachemys scripta in lacking a prominent orange patch on each side of the head. It differs from Pseudemys concinna by having black and yellow concentric circles on the plastron instead of "C" markings (Degenhardt et al. 1996, Ernst and Lovich 2009).
P. nelsoni The Florida redbelly can be distinguished from other similar turtles by its distinctive red-tinged plastron and two cusps on its upper beak. Carapace length in mature turtles can range from 20.3 to 37.5 cm (8.0 to 14.8 in). Females, which average 30.5 cm (12.0 in) in carapace length and weigh 4 kg (8.8 lb), are noticeably larger than males, which are around 25 cm (9.8 in) and 1.8 kg (4.0 lb) in mass. Highly domed shell. Pseudemys nelsoni usually has strong reddish to orangish tint on plastron that is very distinctive in young. Juveniles also exhibit plastral markings in complete semicircular form also the seams of the plastron. Broad vertical stripe on second costal is also indicative of this species. Few head stripes are seen but a light stripe running between the eyes creates an arrowhead pointing at the snout. The notch on the upper jaw of the Florida Redbelly is bordered on either side by strong cusps.
P. rubriventris Females may reach up to 40 cm, but average about 30 cm and 3 kg mass; male maximum size has been reported as 29.5 cm.
P. texana The Texas river cooter is a relatively large turtle, capable of growing to a shell length of 12+ inches (30.5 cm). They are green in color, with yellow and black markings that fade with age. Males can be distinguished from females by their longer tails, longer claws, and overall smaller size. The red-eared slider (Trachemys scripta elegans) shares its range and habits, but can easily be distinguished from the Texas cooter by red patches on either side of its head. Various species of map turtle can also look much like juvenile Texas cooters.
Life Cycle See table:

Species Info
P. alabamensis Nesting of the red-bellied turtle occurs from May through July. Female turtles lay their eggs on dry land, digging nests in sandy soil, where 4 to 9 eggs are laid. Hatchlings usually emerge during the summer. However, when the turtles nest in late July, hatchlings may overwinter in the nest and emerge the following spring. Many aspects of the life cycle of the species are poorly understood, and little is currently known about its courtship, mating, and reproductive habits. Females lay their eggs from April to early August, leaving the water to seek dry ground for nesting sites. The female digs a shallow nest in generally sandy soil and deposits between four and nine eggs. Hatchlings usually emerge during the summer, but if the turtles nest in late July, the young may spend all winter underground and emerge the following spring. The lifespan of the Alabama red-bellied turtle is not known at this time, but most turtle species are long-lived, and life spans of over 50 years are normal for healthy individuals in the Emydidae family.
P. concinna Can live 40 years or more.

Mating habits: Very similar to those of a red-eared slider. As with the other basking turtles, the males tend to be smaller than females. The male uses his long claws to flutter at the face of the much larger female. Often, the female ignores him. After detecting what may be a pheromone signal while sniffing at a female's tail, a male river cooter will court a female by swimming above her, vibrating his long nails and stroking her face. Females have also been observed doing this to initiate courtship. If the female is receptive, she will sink to the bottom of the river and allow the male to mount for mating. The age and size at which maturity is reached in the river cooter varies slightly with location although typically males become sexually mature at about 6 years old and females between 13 and 24 years old. Mating in this species occurs in early spring.

Nesting: The nesting season lasts from May through to the end of June, with nesting typically taking place during the day, usually not far from the river. They often cross highways looking for suitable nesting spots, with sandy or loamy soil within 30 m (100 ft) of the river’s edge, open with no major obstacles for the future hatchlings to negotiate on their way to the river. The female digs a flask-shaped nest cavity using only her hind feet, within which between 12 and 20 eggs are laid. Female river cooters produce up to six clutches per year, although two is most common.

Eggs and hatchlings: The eggs are incubated for a period of between 70 and 96 days depending on the temperature of the soil, typically hatching in August or September. Sex is temperature-dependent. At incubation temperatures of between 22.5 and 28 degrees Celsius, the clutch will contain mostly males, whereas at temperatures of 29 degrees Celsius and above, females will be produced. Eggs are ellipsoidal, approximately 1.5 inches (4 cm) long. There have been reported instances of late clutches over-wintering and hatching in the spring. A hatchling will have a round carapace, about 1.5 inches (4 cm) diameter, that is green with bright yellow markings.

P. gorzugi Limited information is available on reproduction: a clutch size of nine eggs has been reported; whether females produce multiple clutches remains unknown. Age and size at maturity remain unrecorded. In New Mexico, destroyed nests and gravid females have been found in late May; one gravid female contained 9 eggs; recently emerged hatchlings were found in mid-April (these evidently overwintered in the nest), mid-August, and late October (Degenhardt et al. 1996). Life-span data are unavailable, but undoubtedly some individuals live at least a few decades.
P. nelsoni Noted for sometimes laying their eggs in the nest mounds of alligators.
P. rubriventris Age at maturity may be reached at nine years in males (Graham 1971) and 29 cm carapace length (CL), 11 years in females (Swarth 2003). Females may produce two clutches of on average 12 eggs (range 4-22) annually. Hatchlings average 32 mm CL (range 25-36) and 7.8 (4.8-11) grams. Longevity and generation time have not been estimated.
Ecology, Habitat and Diet See table:

Species Info
P. alabamensis Habitat: Fresh to brackish waters: Most abundant in quiet backwaters of upper Mobile Bay in areas with dense submerged vegetation, in water generally 1 to 2 m deep; also in river channels; occurs only as a straggler in brackish water and salt marsh areas of lower Mobile Bay. Basks on dense beds of aquatic vegetation. Prefers soft sandy bottoms in shallow areas of slow-moving freshwater streams and rivers but can also be found in the more brackish waters of bays and bayous in or adjacent to Mobile Bay. These areas are also abundant in the aquatic plants that form the basis of the turtle's diet.

Predators: Red-bellied turtle eggs are an important food source for raccoons and fish crows, among other predators in the area, and the young are preyed upon by large fish, shore birds, snakes, and some mammals. Adults have few predators, but alligators are known to feed on them. Many adult turtles bear tooth scars on their shells from alligator attacks. Additionally, fire ants have been observed in some nest chambers.

Diet: Submergent aquatic macrophytes, such as hydrilla, brushy pondweed, eel-grass, arrowhead, and mud plantain.

P. concinna Habitat: Freshwater. Usually found in medium to large rivers and streams with clear water, moderate to fast current, and extensive aquatic vegetation. Also lakes and tidal marshes. River cooters live in a wide variety of freshwater and even brackish locations. Rivers, lakes, ponds and marshes with heavy vegetation provide ideal habitat. Large webbed feet make the river cooter an excellent swimmer, capable of negotiating moderately strong river currents of major river systems. They will collect in large numbers on peninsular floodplains associated with a river oxbow. Stretches of river 100 centimetres or more deep are ideal. Prefer areas with abundant basking sites such as rocks and partially submerged logs. Also occurs in reservoirs, impoundments, ponds and swamps. In these habitats, this species is typically found in shallower areas.

Predators: As an adult, the river cooter has very few natural predators, but nests are often raided by fish crows (Corvus ossifragus), raccoons (Procyon lotor) and grey foxes (Urocyon cinereoargenteus).

Diet: While the species is highly omnivorous, river cooters will eat anything, plant or animal, dead or alive. Diet seems to be determined by available food items. While some writers feel that these turtles will not eat meat, predatory behavior has been observed. Although this animal cannot swallow out of water, it will leave the water to retrieve a tasty bug or worm, returning to the water to swallow. Cooters will also enthusiastically chase, kill and eat small fish. They have also been observed eating carrion found along the river's edge. River cooters have tooth-like cusps in the upper jaw, probably an adaptation to aid in eating leaves and fibrous vegetation. Their primary diet would include a wide variety of aquatic plants, and some terrestrial plants that grow near the water's edge. They will happily take fallen fruits as well. In captivity, any kind of plant will be eaten, and some "meats", too. Turtles will also take calcium in a separate form, such as a cuttlebone, so that the turtle can self-regulate calcium intake. In the wild they feed on aquatic plants, grasses, and algae. Younger ones tend to seek a more protein enriched diet such as aquatic invertebrates, crustaceans, and fish. Older turtles may occasionally seek prey as well, but mostly partake of a herbivorous diet.

P. gorzugi Habitat: Creeks, rivers, lakes and ponds that comprise the Pecos and Rio Grande River systems.

Diet: Omnivorous consuming wide range of aquatic invertebrates and plants adults shift towards a mostly herbivorous diet. Examined gut contents were entirely vegetarian (Legler, in Ernst and Lovich 2009), although the species has also been thought to be omnivorous (Degenhardt et al. 1996, Ernst and Lovich 2009).

P. nelsoni Habitat: Can be found in nearly any type of aquatic habitat. It reaches particularly high densities in spring runs, and occasionally can be found in brackish water. Pseudemys nelsoni inhabits a variety of freshwater habitats with abundant vegetation, including ditches, wetlands, marshes, ponds, lakes, and streams, mangrove-bordered creeks slow-flowing rivers and spring runs. Some individuals occur in brackish (30% saltwater) situations. Pseudemys nelsoni can be found in streams, ponds, lakes, ditches, sloughs, marshes and mangrove-bordered creeks. Usually water with rich aquatic plant life.

Diet: Strictly herbivorous after its early juvenile years, feeding on a variety of aquatic plants.

P. rubriventris Habitat: Inhabits large deep water bodies, such as rivers, lakes, impoundments,canals, tidally-influenced lower river areas and large wetlands as adults, while juveniles tend to occur in more sheltered, standing waters such as ponds, marshes, creeks and swamps. The presence of basking sites and extensive aquatic vegetation beds is required.

Diet: Red-bellied turtles are nearly exclusively herbivorous, feeding on a variety of aquatic plants; juveniles take some small animal prey as well.

Behavior and Locomotion All are aquatic and can easily be seen basking on rocks on logs in sunny weather.

Species Info
P. alabamensis Spends a great deal of time either foraging or basking on logs.
P. concinna Can move with surprising speed in the water and on land. Enjoy basking on logs or sun-warmed rocks and are frequently found in the company of other aquatic basking turtles (sliders and painteds) sometimes piled up on top of each other. All are quick to slip into the water if disturbed. It is not unusual for them to wander from one body of freshwater to another, but many seem to develop fairly large home ranges, which they seldom or never leave. They sleep in the water, hidden under vegetation. The river cooter is mostly diurnal, foraging underwater in the early morning and late afternoon and spending much of the rest of its day basking in the sun with other individuals of its kind.

Dormancy: While those that live in areas that are quite warm remain active all winter, river cooters in cooler climes can become dormant during the winter for up to two months, in the mud or at the bottom of the watery habitat, underwater. They do not breathe during this time of low metabolism, but can utilize oxygen from the water, which they take in through the cloaca. River cooters prefer to be well hidden under aquatic plants during the winter dormancy period or while sleeping each night.

P. gorzugi Aquatic, diurnal and fond of basking on shorelines, emergent logs rocks and vegetation. Wary and at the slightest disturbance will slip into the safety of the water. These turtle are nonmigratory, although reproductive females move unknown distances between aquatic habitat and terrestrial nesting areas. Based on limited radio-tracking data, Degenhardt et al. (1996) regarded this species as rather sedentary; individuals tended to stay in the same small river reach; researchers recorded one movement of approximately 300 meters.
P. nelsoni This species is active year-round and spends a large portion of the day basking on logs. Closely related to the Peninsula cooter (P. peninsularis) and can often be found basking on logs together.
Conservation Status and Efforts See table:

Species Info
P. alabamensis Status EN (possibly CE).
P. concinna Status LC.
P. gorzugi Status NT.
P. nelsoni Status LC.
P. peninsularis Status LC.
P. rubriventris Status NT.
P. texana Status LC.
Distribution Eastern US and northeastern Mexico.

Species Info
P. alabamensis Formerly throughout the lower part of the Mobile River system below David Lake, Baldwin and Mobile counties, Alabama; as far north as the Little River State Park in southern Monroe County, and perhaps east into the Florida Panhandle as far as Apalachee Bay. Current distribution: Mobile Bay (the Mobile-Tensaw River Delta in Mobile and Baldwin counties) and tributary streams, e.g. Bayou La Batre, Fowl, Dog, Fish, Mangolia, and Bon Secour. As of June 2009 the turtle has been seen in the central part of Alabama, in the Elmore County region. This turtle has also been found in south-eastern Mississippi, in Harrison and Jackson counties, in the Pascagoula river.
P. concinna Native to the central and eastern United States, from Virginia south to mid-Georgia, west to eastern Texas, Oklahoma, and north to southern Indiana.

Eastern river cooter: Sabine-Missouri-Mississippi-Ohio basins, and Atlantic rivers above the fall line in the southeast, and from the Apalachicola westward in the Florida Panhandle.

Florida cooter: Coastal plain from North Carolina to Louisiana below the fall line.

Suwannee cooter: West coast of peninsular Florida, eastward of the Ochlockonee River.

P. gorzugi The Rio Grande drainage of Mexico (Chihuahua, Coahuila, Nuevo León, Tamaulipas), New Mexico, and Texas. Pseudemys gorzugi inhabits the Pecos-lower Rio Grande basin from New Mexico through Texas, USA, and Coahuila, Nuevo Leon and Tamaulipas, Mexico (Iverson 1992, Seidel 1994). Not recorded from the Rio Grande at or above the Big Bend region, nor from the San Fernando. Upper elevation limit of 1082 m.
P. nelsoni Endemic to Florida, and southern Georgia. Pseudemys nelsoni is found throughout peninsular Florida, in the Okefenokee Swamp of southern Georgia, and in an isolated population in the Florida panhandle, near Tallahassee. Introduced populations have been reported from San Marcos, Texas, and Tortola, British Virgin Islands (Jackson 2010).
P. peninsularis Widespread in peninsular Florida. The precise northern limits of occurrence are unclear given the historically complicated taxonomy and identification of individuals and the wide zone of apparent intergradation with floridana from Ocala to Tallahassee (Thomas and Jansen 2006, Ernst and Lovich 2009).
P. rubriventris The current range of the red-bellied turtle includes a population in Massachusetts which was previously considered a distinct subspecies (P. r. bangsii) as well as the coastal areas of New Jersey, Pennsylvania, Delaware, Maryland, Virginia and North Carolina.
P. texana Native to creeks, rivers, and lakes of Texas. It is found in the river basins of the Colorado, Brazos, Guadalupe, and San Antonio Rivers. It is one of two species of cooter native to Texas, the other being the Eastern River Cooter.
Miscellaneous Information P. alabamensis is the state reptile of Alabama. In captivity, river cooters (P. concinna) need an aquatic habitat, with a dry basking area. They need a warming light and UVB radiation (from reptile lights or direct sunshine). As juveniles, they can be kept in a 20- or 30-gallon long tank, but they will outgrow those accommodations, and need a very large tank or outdoor pond.

#### Genus Clemmys (spotted turtle)

Clemmys belongs to the subfamily Emydinae and has one species, C. guttata. Originally, Clemmys had four species, but they have since been moved (the bog turtle, Glyptemys muhlenbergii, the spotted turtle C. guttata, the western pond turtle Actinemys marmorata, and the wood turtle Glyptemys insculpta).

#### Genus Glyptemys (sculptured turtles - wood and bog turtles)

Glyptemys belongs to the subfamily Emydinae and comprises two species (the wood turtle G. insculpta and the bog turtle G. muhlenbergii). This genus used to belong to Clemmys. There are no recognized wood turtle subspecies although there are morphological differences between areas.

#### Genus Deirochelys (chicken turtle)

Deirochelys belongs to the subfamily Deirochelyinae and has one species, D. reticularia, which has three subspecies, the eastern chicken turtle D. r. reticularia, the Florida chicken turtle D. r. chrysea, and the western chicken turtle D. r. miaria.

Picture(s) American snake necks Chicken turtles taste like chicken. Similar in appearance to the eastern painted turtle (Chrysemys picta picta) Distinctive features: An unusually long neck that is close to the length of plastron (up to 80% of carapace) and striped with yellow. A yellow stripe on both the forelegs and rear legs. Adaptations: Webbed feet to help it swim. Shell: Pale-yellowish net-like pattern on carapace. Pear-shaped carapace that is olive to dark brown. Plastron is usually solid yellow and unmarked. Sexual dimorphism: Females usually larger than the males. Males have a bigger, longer tail. Males have longer front claws. Males have more compressed shells. Size: 15-23 cm (6-9 in). Up to 25 cm (10 in). Typical adult ranges from 15.3-17.8 cm (6-7 in). Medium in size compared to other turtles. Wild chicken turtles have been recaptured up to 15 years after their first capture. Some reached the known maximum ages of 20 to 24 years. Shorter life history than many other turtles in Georgia. Breeding: Males reproduce with female chicken turtles by vibrating the fore-claws against the female's face. Once the female is receptive, copulation occurs. Chicken turtles are different from most other North American turtles because they nest in late summer, fall, or winter. In South Carolina, there are two-egg laying seasons; from winter to early spring (February to may) and fall to early winter (August to November). Females excavate cylindrical nest on land in a variety of soil types, from sandy to heavy soils. Eggs: Females lay 2 to 19 clutches of eggs. Chicken turtle embryos go through a period of diapause in the late gastrula stage. They must experience a period of cool temperatures before development proceeds. Eggs hatch in 152 days at 29 Celsius in South Carolina, and some eggs may overwinter in the nest before hatching. They can emerge a year or more after the eggs were laid in Georgia. Incubation temperature influences the sex of the embryos, with a 25 degrees Celsius incubation temperature resulting in all males. Warmer temperatures result in an increase in female embryos, with only 11 percent becoming males at incubation temperatures of 30 degrees Celsius. Chicken turtles are 2.5 cm (1 in) in diameter at birth. Habitat: Chicken turtles are semi-aquatic turtles, found both in water and on land. They prefer quiet, shallow, and still bodies of water such as shallow ponds and lakes, ditches, marshes, cypress swamps, and Carolina bays. They prefer water with dense vegetation and soft substrate (e.g. seasonal wetlands with abundant vegetation). Chicken turtles are tolerant of ephemeral aquatic habitats (made up of plants with short life cycles) and readily travel onto land to burrow into the soil and escape dry conditions. They have been found at depths of a few centimeters to more than 2 m. They are generally absent from large permanent ponds and reservoirs. Predators: Eastern moles (Scalopus aquaticus) are significant predators of chicken turtle nests. Raccoons (Procyon lotor) and snapping turtles (Chelydra serpentina) are potential predators. Chicken turtles are both predator and prey. Diet: Chicken turtles are omnivorous, eating crayfish, small fish, fruits, insects, invertebrates, frogs, tadpoles, and plants. During the first year of their lives, they are almost completely carnivorous. Although they are mostly carnivorous at birth, they still eat plants. The chicken turtles uses its well-developed hyoid apparatus to create suction that pulls food items into its throat, which is very unusual. Chicken turtles impact populations of aquatic insects, crustaceans, tadpoles, and aquatic vegetation. Chicken turtles are regularly encountered on land, migrating between aquatic habitats or seeking areas to burrow into the soil and escape dry conditions. Males generally travel around farther than females. They are social, spending much of their time basking on logs and rocks and swim in small groups. Chicken turtles become dormant in the soft mud, but only in the northern part of their range, and vegetation of bodies of water. They are known to be timid but if caught they generally will bite very easily. They spend most of their time in the water. They are among the most territorial of turtles. Nearly all males and some females leave the wetland each fall to spend the winter buried in the forest. Chicken turtles estivate during drought in uplands rather than migrating to other wetlands. Chicken turtle populations are currently considered stable throughout their range, although they do face potential threats. The eastern chicken turtle species is listed as state threatened in Virginia. Habitat destruction reduces suitable habitat for foraging, migration, and brumation. Chicken turtles are sometimes killed on roads as they migrate between habitats. Hunting for food impacts populations of chicken turtles as well. Chicken turtles are potentially vulnerable to habitat loss and degradation. Much that is known about the ecology of chicken turtles comes from population studies conducted at the Savannah River Ecology Lab, particularly the work of Dr. Kurt Buhlmann. Chicken turtles have no special status in the IUCN Red List or CITES. Coastal areas from Virginia to Texas and northward into Oklahoma and Arkansas: D. r. chrysea is limited to peninsular Florida, and D. r. reticularia and D. r. miaria are separated by the Mississippi River. Chicken turtle meat used to be popular in the southern US.

#### Genus Emydoidea (Blanding’s turtles)

Emydoidea belongs to subfamily Emydinae and has one species, E. blandingii.

### Family Testudinidae (tortoises)

Family Testudinidae has 15 genera and 45 species.

Picture(s) See #Order Testudines/Chelonia. A&P: Pectoral and pelvic girdles are inside rib cage (unique among vertebrates). Almost all have domed shells. Columnar/elephantine feet. Vary in size from a few centimeters to two meters. Sexual dimorphism: Many species of tortoises are sexually dimorphic, though the differences between males and females vary from species to species. In some species, males have a longer, more protruding neck plate than their female counterparts, while in others, the claws are longer on the females. In most tortoise species, the female tends to be larger than the male. The male plastron is curved inwards to aid reproduction. The easiest way to determine the sex of a tortoise is to look at the tail. The females, as a general rule, have smaller tails, dropped down, whereas the males have much longer tails which are usually pulled up and to the side of the rear shell. Brain: The brain of a tortoise is extremely small. The tortoises, from Central and South America, do not have an area in the brain called the hippocampus, which relates to emotion, learning, memory and spatial navigation. Studies have shown that red-footed tortoises may rely on an area of the brain called the medial cortex, an area that humans use for actions such as decision making. In the 17th century, Francesco Redi performed an experiment that involved removing the brain of a land tortoise, which then proceeded to live six months. Freshwater tortoises, when subjected to the same experiment, continued similarly, but did not live so long. Redi also cut the head off a tortoise entirely, and it lived for 23 days. Shell: Most tortoises have a large and dome-shaped shell that makes it difficult for predators to crush the shell between their jaws (one of the few exceptions is the African pancake tortoise, which has a flat, flexible shell that allows it to hide in rock crevices). Lifespan: Galápagos tortoises are noted to live over 150 years, but an Aldabra giant tortoise named Adwaita may have been the longest living at an estimated 255 years. The oldest tortoise ever recorded, and one of the oldest individual animals ever recorded, was Tu'i Malila, which was presented to the Tongan royal family by the British explorer Captain Cook shortly after its birth in 1777. Tu'i Malila remained in the care of the Tongan royal family until its death by natural causes on May 19, 1965, at the age of 188. The record for the longest-lived vertebrate is exceeded only by one other, a koi named Hanako whose death on July 17, 1977, ended a 226-year lifespan. The Alipore Zoological Gardens in India were the home to Adwaita, which zoo officials claimed was the oldest living animal until its death on March 23, 2006. Adwaita (sometimes spelled with two ds) was an Aldabra giant tortoise brought to India by Lord Wellesley, who handed it over to the Alipur Zoological Gardens in 1875 when the zoo was set up. West Bengal officials said records showed Adwaita was at least 150 years old, but other evidence pointed to 250. Adwaita was said to be the pet of Robert Clive. Harriet was a resident at the Australia Zoo in Queensland from 1987 to her death in 2006; she was believed to have been brought to England by Charles Darwin aboard the Beagle and then on to Australia by John Clements Wickham. Harriet died on June 23, 2006, just shy of her 176th birthday. Timothy, a spur-thighed tortoise, lived to be about 165 years old. For 38 years, she was carried as a mascot aboard various ships in Britain's Royal Navy. Then in 1892, at age 53, she retired to the grounds of Powderham Castle in Devon. Up to the time of her death in 2004, she was believed to be the United Kingdom's oldest resident. Jonathan, a Seychelles giant tortoise living on the island of St Helena, may be as old as 182 or 178 years. Breeding: Female tortoises dig nesting burrows in which they lay from 1 to 30 eggs. Egg-laying typically occurs at night, after which the mother tortoise covers her clutch with sand, soil, and organic material. The eggs are left unattended, and depending on the species, take from 60 to 120 days to incubate (100 days to 18 months?). The size of the egg depends on the size of the mother and can be estimated by examining the width of the cloacal opening. The plastron of a female tortoise often has a noticeable V-shaped notch below the tail which facilitates passing the eggs. Upon completion of the incubation period, a fully formed hatchling uses an egg tooth to break out of its shell. It digs to the surface of the nest and begins a life of survival on its own. They are hatched with an embryonic egg sac which serves as a source of nutrition for the first three to seven days until they have the strength and mobility to find food. Juvenile tortoises often require a different balance of nutrients than adults, so may eat foods which a more mature tortoise would not. For example, the young of a strictly herbivorous species commonly will consume worms or insect larvae for additional protein. Growth rings: The number of concentric rings on the carapace, much like the cross-section of a tree, can sometimes give a clue to how old the animal is, but, since the growth depends highly on the accessibility of food and water, a tortoise that has access to plenty of forage (or is regularly fed by its owner) with no seasonal variation will have no noticeable rings. Moreover, some tortoises grow more than one ring per season, and in some others, due to wear, some rings are no longer visible. Habitat: Terrestrial (desert, grassland, scrub) Diet: Most land-based tortoises are herbivores, feeding on grasses, weeds, leafy greens, flowers, and some fruits, although some omnivorous species are in this family. Pet tortoises typically require diets based on wild grasses, weeds, leafy greens and certain flowers. Certain species consume worms or insects and carrion in their normal habitats. Too much protein is detrimental in herbivorous species, and has been associated with shell deformities and other medical problems. As different tortoise species vary greatly in their nutritional requirements, it is essential to thoroughly research the dietary needs of individual tortoises. Usually diurnal. Crepuscular depending on ambient temperature. Generally reclusive. Dormancy: The tortoise starts digging the ground to form its hybernaculum at the first signs of autumn. It digs with its fore-feet in a very slow motion, and prefers swampy grounds where it could bury itself in mud. It starts losing its appetite for food as the temperature drops until it stops eating. During hibernation it stops breathing as well. When the weather warms up suddenly it stops its digging, and starts it again as soon as the temperature drops. It wakes up from hibernation in the spring, but it does not start eating immediately. Gradually it gains its appetite and energy as the temperature warms up. During hot summer days, tortoises eat voraciously, and spend many hours sleeping. They start sleeping in late afternoon until late the next morning. Although tortoises love warm weather, they avoid hot sun, hiding under green leaves or between vegetation. Locomotion: Giant tortoises move very slowly on dry land (0.17 mph or 0.27 km/h). The fastest recorded tortoise speed is 5 mph (8.0 km/h). According to the IUCN, one species is Critically Endangered or facing an extremely high risk of extinction in the wild, seven are Endangered or facing a very high risk of extinction in the wild, and sixteen are Vulnerable or facing a high risk of extinction in the wild. The U.S. Fish and Wildlife Service lists two U.S. species as Threatened or likely to become endangered in the near future and five foreign species as Endangered, or in danger of extinction throughout all or a significant portion of their range. Although most countries make collecting illegal, it still continues. People find these land-living turtles easy to find and collect. Southern North America to southern South America, circum-Mediterranean Euroafrica to Indomalaysia, sub-Saharan Africa, Madagascar, and some oceanic islands. Symbolize longevity in some cultures such as the Chinese. In Hinduism, Kurma (Sanskrit: कुर्म) was the second Avatar of Vishnu. Like the Matsya Avatara, Kurma also belongs to the Satya Yuga. Vishnu took the form of a half-man, half-tortoise, the lower half being a tortoise. He is normally shown as having four arms. He sat on the bottom of the ocean after the Great Flood. A mountain was placed on his back by the other gods so they could churn the sea and find the ancient treasures of the Vedic peoples. Tortoise shells were used by ancient Chinese (Shang dynasty) as oracle bones to make predictions. The tortoise is a symbol of the Ancient Greek god, Hermes.

### Family Cheloniidae (sea turtles)

Family Cheloniidae comprises six species in five genera (the green/black (sea)/Pacific green turtle Chelonia mydas, the loggerhead sea turtle Caretta caretta, the olive ridley/Pacific ridley sea turtle Lepidochelys olivacea, Kemp's ridley/the Atlantic ridley sea turtle L. kempii, the hawksbill sea turtle Eretmochelys imbricata, and the Australian flatback sea turtle Natator depressus).

Picture(s) Cheloniids The fat of the green turtle is green. The only unifying skeletal feature is the platycoelous (one surface flat and one concave) articulation between the sixth and seventh cervical vertebrae. The smallest species is L. kempii (75 cm and 50 kg). The largest species is C. caretta (213 cm). Shell: Most aquatic turtles have flat, streamlined, wide, and rounded shells which aid in swimming and diving. Incompletely retractile or nonretractile head. Considerably reduced plastron that is connected to carapace by ligaments without a hinge separating the pectoral and abdominal plates of plastron. Oval or heart-shaped. Horny scutes (variable in number, commonly include five vertebrals and six pairs of plastral scutes and usually both an intergular and an interanal scute). Plastron often with persistent fontanelles (one in middle and others in entoplastral and xiphiplastral regions). Hyoplastra and hypoplastra not suturally connected mesially (in the middle) but each with a series of coarse spikes that interdigitate (interlock like fingers of hands put together) mesially. Plastron not cruciform. Posterior plastral lobe relatively long and wide. Skull: Extensively roofed. Well-developed rhamphothecae (thin horny sheaths of keratin that cover the beaks). Secondary palate. Limbs: Almost paddle-like flippers for forelimbs. Only turtles where front limbs are stronger than back limbs. Limbs cannot support body weight on land. Webbed hind limbs for steering. Covered with numerous small scales. Highly elongate digits firmly bound together by connective tissue. One or two claws on each limb. Radius and ulna cannot move independently because of juxtaposed rugose (wrinkled) surfaces. Reproductive behaviors among the different species of sea turtles are similar, with slight differences in each of the species. The females come to shore and bury their clutch of eggs on beaches or sandy environments typically at night and well away from the high tide line of the shore. Most females nest only once every three to four years and most species have two to four egg laying time periods per nesting season, which is from spring to late fall. A common number of eggs laid in a nest is often about 100 eggs per clutch. The incubation period of some turtles can range anywhere from 50 to 60 days. The development of the eggs is dependent on the temperature of the environment that they were buried in, with warmer climates bringing about an earlier emergence by the hatchlings. The timing of sea turtle hatching tends to be almost synchronous among the whole clutch of eggs, with just about all the eggs in the nest hatching within the same time. This is thought to aid the process of the hatchlings unburying themselves from the sand and most often occurs at night time. Interestingly enough, temperature has also been linked to the likeliness of hatching's sex, warmer temperature more likely to produce females and colder temperatures more commonly producing males. Courtship and mating usually occur in shallow offshore waters. Mating often involves the male and female pair floating near the surface, with the male's carapace protruding from the water. Females reproduce on multi-year cycles, but produce multiple clutches within a single season. Nesting occurs at night (except in Lepidochelys), and a range of seven to 238 eggs (averages vary across species) are deposited in a single clutch. Require 25 years for sexual maturity. Habitat: The habitat range of sea turtles, in general, is known to be far reaching into warmer temperatures and the tropical and subtropical areas of the Pacific and Atlantic Oceans and is even also found in warmer seas such as the Mediterranean Sea. Within these temperamental biomes, sea turtles frequent nearby the coastlines when nesting, and spend most of their lives swimming out in waters over the continental shelf when feeding. Travelling throughout the oceans has been reported in Olive Ridleys Sea Turtles but more often than not, they tend to frequent bays and estuaries. Marine. Predators: Adult turtles have relatively few natural predators, although sharks and saltwater crocodiles are known to consume adults, and nesting females are preyed upon by coyotes and other canids. Eggs and hatchlings are the most vulnerable, falling prey to insects, crustaceans, mollusks, small mammals, birds, other reptiles, and various fishes. Diet: The diets of all the sea turtle species, except for the green turtle, which is only carnivorous from hatchling to juvenile, are mostly carnivorous, with some herbivorous tendencies. Turtles feed mainly on sea sponges, jellyfish, mollusks and barnacles, sea urchins, and even fish. The green sea turtle, on the other hand, feeds primarily on many different types of sea grasses. Sea turtles are omnivorous and feed on a variety of sponges, cnidarians, mollusks, crustaceans, algae, plants, and fish. The conservation status of each of the seven turtle species are mostly all endangered or threatened. The green and loggerhead sea turtles are categorized as endangered, olive ridleys are classified as vulnerable, Kemp’s ridleys, and hawksbills sea turtles are critically endangered and the flatback sea turtle does not have enough data to draw an accurate conclusion on conservation status. This is due to their slow growth rate to full maturity. Many do not ever make it to full adulthood because of being caught, either intentionally or by accident by big fisheries and fishermen. Their slow maturity rate, which most of the time means about 10 or 15 years, does not allow the turtles to fully reproductively mature to have hatchlings of their own. International legislation has been put into place to attempt to reduce the number of sea turtle deaths but this does not deter the demand for the consumption of turtle eggs around the world, and some are hunted for their shells. In addition to this, turtles face another threat which has been theorized as being linked to human pollution. A growing number of turtles have been found with fibrous tumor-like growths on their skin, mouths, and even internal organs with no clear cause having been found to be the cause of this disease, and in some areas the number of infected turtles reaching over 70%. It is unknown what the effects of the growths will have in the long term for sea turtle populations. Sea turtles play a very important part in marine ecosystems. They maintain the balance of health of sea grasses and reefs, which in turn benefit the likes of shrimp, lobsters, and tunas. They are also the last living members of the seafaring category of marine reptiles that have been in existence on Earth for at least the past 100 million years. Additionally, they are also highly significant to multiple cultures and are also popular touristic animals, which give them lots of value to their conservation. Temperate and tropical regions of the Atlantic, Pacific, and Indian Oceans. Typically found from North Carolina to Florida but ranges from Newfoundland to Argentina. Primarily nest in the Atlantic and Indian Oceans. Most records of loggerheads in the Pacific are sightings of juveniles off the coasts of California and Mexico. Also records in Mediterranean Sea. Some populations remain primarily in the coastal continental shelf regions near their nesting sites while other populations are known to migrate across deep waters. Ranges from sea level (where sea turtles lay their eggs) to pelagic ocean (where adults spend majority of their time). Less is known about where young and juvenile turtles spend their lives but it is believed that the young take refuge in nearshore coastal areas and that once they reach the open oceans juveniles still live primarily in the upper fifteen feet (five meters) of the water column. A group of sea turtles is a bale. The fossil record for Cheloniids places them among the oldest turtles. Six extinct genera, as well as the extant genera Caretta and Chelonia, date from the Upper Cretaceous of Europe and North America. The leatherback sea turtle (Dermochelys coricea) is not part of Cheloniidae but in Dermochelyidae.

### Family Trionychidae (soft shelled turtles)

Trionychidae consists of the subfamilies Cyclanorbinae and Trionychinae. Many species were traditionally in Trionyx but have since been moved.

Picture(s) Pancake turtles "Softshell" - Carapaces lack horny scutes; "Trichonyidae" - three claws. Shell: Carapaces lack horny scutes (though the spiny softshell, Apalone spinifera, does have some scale-like projections, hence its name). Carapace is leathery and pliable particularly at the sides. Central part of carapace has a layer of solid bone beneath it as in other turtles (but this is absent at the outer edges). Some species also have dermal bones in the plastron but these are not attached to the bones of the shell. Lattice-like plastron (either fused or separate). Adaptations: Light and flexible shell of these turtles allows them to move more easily in open water and muddy lake bottoms. Having a soft shell also allows them to move much faster on land than most turtles. Their feet are webbed and are three-clawed. The carapace color of each type of softshell turtle tends to match the sand and/or mud color of its geographical region, assisting in their "lie and wait" feeding methodology. Many must be submerged in order to swallow their food. They have elongated, soft, snorkel-like nostrils. Their necks are disproportionately long in comparison to their body sizes, enabling them to breathe surface air while their bodies remain submerged in the substrate (mud or sand) a foot or more below the surface. Softshells are able to "breathe" underwater with rhythmic movements of their mouth cavity that contains numerous processes that are copiously supplied with blood, acting similarly as gill filaments in fish. Cutaneous (relating to the skin) respiration. This enables them to stay underwater for prolonged periods. Moreover, the Chinese softshell turtle has been shown to excrete urea while "breathing" underwater; this is an efficient solution when the animal does not have access to fresh water, e.g., in brackish-water environments. Forelimbs substantially modified into swimming paddles. Sexual dimorphism: Females can grow up to several feet in carapace diameter while males stay much smaller. Size: Pelochelys cantorii (found in southeastern Asia) is the largest softshell turtle (70-100 cm and can grow to over 100 kg). Mandibles: According to Ditmars (1910): "The mandibles of many species form the outer border of powerful crushing processes—the alveolar surfaces of the jaws", which aids the ingestion of tough prey such as molluscs. These jaws make large turtles dangerous, as they are capable of amputating a person's finger, or possibly their hand. Courtship has been observed in a few species and involves acts such as head bobbing between a pair in some and the male rubbing the carapace of the female with his head in others. Overall, however, knowledge of reproductive behavior is poor. Females reproduce annually, and nests contain around 20 eggs. More than one clutch per season is often produced. Habitat: Include slow moving streams, swift rivers, lakes, ponds, and even brackish waters, but a soft bottom is requisite. Diet: Most are strict carnivores, with diets consisting mainly of fish, aquatic crustaceans, snails, amphibians, and sometimes birds and small mammals. Opportunistic. Spend much time buried in the mud, and basking is not common. According to the IUCN, more than half of the family's 25 species are at risk. Five species are Critically Endangered, which means that they are facing an extremely high risk of extinction in the wild. In addition, five are Endangered and face a very high risk of extinction in the wild, and six are Vulnerable and at high risk of extinction in the wild. The U.S. Fish and Wildlife Service also lists four non-U.S. species as Endangered, or in danger of extinction throughout all or a significant portion of their range. Softshells are coping with overhunting, polluted waters that can weaken and/or kill the animals, and loss of their habitat. As food: Softshell turtles are eaten as a delicacy in most parts of their range, particularly in East Asia. A Chinese dish stews them with chicken. According to a 1930 report by Soame Jenyns, Guangdong restaurants had them imported from Guangxi in large numbers; "eaten stewed with almonds, roast with chili sauce or fried with bamboo shoots, they [were] considered a great delicacy." World-wide, the most commonly consumed softshell species is the Chinese softshell Pelodiscus sinensis. As noted Japanese biologist Kakichi Mitsukuri pointed out in 1904, the Japanese variety of this turtle, which at time was classified as Trionyx japonicus, occupied a place in Japanese cuisine as esteemed as the diamondback terrapin in the United States or the green turtle in England. The farming of this "luscious reptile", known in Japan as suppon, was already developed on an industrial scale in that country by the late 19th century. Due to rising demand and overhunting, the price of Pelodiscus sinensis in China skyrocketed by the mid-1990s; large-scale turtle farming in China and neighboring countries; raising this species by hundreds of millions was the response, with prices soon returning to a more affordable level. Another species, Palea steindachneri, is farmed in China, as well, but on a much smaller scale (with farm herds measured in hundreds of thousands, rather than hundreds of millions). In the United States, harvesting softshells (e.g. Apalone ferox) was, until recently, legal in Florida. Environmental groups have been advocating the authorities' banning or restricting the practice. The Florida Fish and Wildlife Conservation Commission responded by introducing the daily limit of 20 turtles for licensed harvesters—a level which the turtle advocates consider unsustainable, as there may be between 100 and 500 hunters statewide. While some catch was consumed locally, most was exported; the Commission estimated (2008) around 3,000 pounds of softshell turtles were exported each week via Tampa International Airport. New rules, in effect as of July 20, 2009, restrict collecting any wild turtles to one turtle per person per day, completely prohibit collection of softshells (Apalone) in May through July, and prohibit trade in turtles caught from the wild. An exemption is provided for licensed turtle farms that need to catch turtles in the wild to serve as their breeding stock. Some other US states, too, have already adopted strict limitations on wild turtle trade. In 2009, South Carolina passed the law (Bill H.3121) restricting interstate and international export of wild-caught turtles (both soft-shell and some other species) to 10 turtles per person at one time, or 20 turtles per person per year. Eastern North America, Africa, Asia, and the Indo-Australian archipelago. Appeared early in fossil record (first appeared in North America and Europe in the Late Cretaceous, or 100.5-66 mya, and Paleocene, 66-55 mya, respectively).