The eastern snapping turtle is a large aquatic turtle with a big, pointed head, long thick tail, and small plastron (lower shell). The carapace (upper shell) may be tan, brown, or nearly black, but it is often covered with mud or algae. The head, tail, and limbs are brown. The head is often covered with numerous small black lines or spots. The plastron and undersides of the limbs are yellowish white. The upper part of the tail has large, pointy scales in a sawtooth row. In young turtles, the carapace has 3 rows of low keels, but these are less apparent in older individuals. The eyes can be seen from above.
Take care if you plan on handling large snapping turtles! They have strong jaws and long necks. Grasping the turtle by the base of the tail (keeping it away from your legs) is safe for you, but it can potentially injure the turtle's backbone. If you must move a large snapper, it is best to consult a wildlife professional.
When taken out of water, snapping turtles will vigorously defend themselves; they will even become aggressive and lunge at any adversary. They are known for a defensive posture of dipping one side of the front shell while raising the opposite back side with a gaping mouth when encountered on land. Once in the water, however, they usually do not bite and will try to hide or escape rather than defend themselves.
Similar species: Missouri's one other species of snapping turtle is the alligator snapping turtle (Macrochelys temminckii). It is rare, declining, and protected by law. In Missouri, it has a much more limited distribution: it mainly occurs in the large rivers, sloughs, and oxbow lakes of our southern, southeastern, and eastern counties. Its upper shell has 3 prominent ridges — 1 along the center line and 1 on either side. The large head terminates in a sharp, strongly hooked beak. The tail is long and muscular. The skin on the head, neck, and forelimbs has a number of fleshy projections or tubercles.
Adult upper shell length: 8–14 inches, occasionally to nearly 20 inches; weight: 10–35 pounds; occasionally to 75 pounds (in the wild) or 86 pounds (captive-raised). Males are slightly smaller than females.
Habitat and Conservation
The eastern snapping turtle lives in a wide variety of aquatic habitats. It commonly occurs in farm ponds, ditches, marshes, swamps, sloughs, rivers, and reservoirs — anywhere there is permanent water. Prefers bodies of water with a mud bottom, abundant aquatic vegetation, and submerged logs and snags. They tend to spend a lot of time hidden in the mud or vegetation in shallow water while awaiting prey to ambush or walking on the bottom searching for food. This species is primarily aquatic and seldom basks in the sun.
Eastern snapping turtles are primarily active between March and November, with a peak in Missouri from May into July. They overwinter in water by burying themselves into the mud bottom, beneath logs and sticks, and within overhanging banks of ponds, lakes, swamps, marshes, or river backwaters. Individuals are occasionally seen slowly moving on the bottom of pond under the ice during the winter in Missouri and other states.
Adult females travel overland during egg-laying season (mid-May into June), and many are killed by vehicles. Both sexes travel overland seeking a new home if their pond dries up.
Conservation of this species involves regulated hunting: Check the Wildlife Code of Missouri for specifics.
Eastern snapping turtles eat a wide variety of animals and plant material. Natural food of this species includes insects, crayfish, fish, snails, earthworms, amphibians, snakes, small turtles, small mammals, birds, and aquatic vegetation. Up to 36 percent of a snapping turtle’s diet may consist of plant material. A large specimen captured in northeastern Illinois was found to have fed, almost exclusively, on duckweed (Lemna spp). Carrion may also be consumed.
To maintain healthy populations of this turtle, harvest is controlled by state regulations. Consult the most recent Wildlife Code of Missouri for current regulations.
Common throughout the state. This species was formerly called the "common snapping turtle," but scientists are now in favor of calling it the eastern snapping turtle. They removed the word "common" from the name because that term might mislead people into thinking this turtle is abundant, when instead it is only the most typical and widespread member of its family.
Courtship and mating can take place between April and November, but mostly in late spring and early summer, when water temperatures are warm. Females can retain viable sperm in their bodies for a number of years; this allows a single female to move into a new area and start a new colony. It also allows a female to mate with multiple males, increasing genetic diversity within a clutch laid by a single female.
Mid-May into June is the usual period for egg-laying. The female selects an area, often quite a distance from water, with deep sand or loose soil, where she will dig out a bowl-shaped nest 3–8 inches deep with her hind limbs. If suitable nest sites are scarce, the female may dig her nest along elevated roadsides, railways, or levees. Clutch size ranges from 4 to more than 100 eggs, with an average of about 25–45.
The eggs are leathery shelled, cream colored, and about the same shape and size as a ping-pong ball. Hatching occurs 55–125 days after the eggs are laid, varying with nest temperature and humidity. Most eggs likely hatch between 75–95 days. Incubation temperature determines the sex of the hatchlings. In natural nests, the eggs on top are warmer than the eggs on the bottom. The higher average temperature causes those eggs to develop mostly into females, while the lower average temperature produces mostly males. This is called temperature-dependent sex determination, and it occurs in other species of Missouri turtles, too.
Males become mature in 4–5 years, and females in 4–7. These turtles generally have a lifespan of 40 years.
The eastern snapping turtle is considered a game animal and is one of the few economically valuable reptile species in the state. Some people actively pursue this species for its meat, which is reported to make a fine stew and an excellent soup. Make sure you know the current regulations regarding their harvest.
Over the years, some people have developed an intense dislike of this species caused by misinformation and a lack of understanding. Field studies have proven that this turtle will not harm game fish populations in natural bodies of water, and that a large part of its diet consists of aquatic vegetation, rough fish, crayfish, and carrion. Contrary to popular belief, snapping turtles do not cause substantial damage to waterfowl young under natural conditions; that myth was disproven in the 1940s. However, in artificial ponds where fish or waterfowl production is enhanced, this species may become a serious nuisance; control measures to reduce numbers of individuals may be required.
These turtles help to keep the populations of many aquatic animals (and aquatic plants) in check. Meanwhile, studies have shown that up to 84 percent of nests can be destroyed by hungry predators such as skunks, raccoons, and mink.
Because these turtles eat a wide variety of plant material as well as animals, recent diet studies have shown the important role they play in seed dispersal and germination of plants. A study in Christian County, Missouri, showed that eastern snapping turtles were important for seed dispersal of mulberries (Morus spp.), barnyard grass (Echinochloa crus-galli), and curly dock (Rumex crispus).
The snapping turtle family (Chelydridae) comprises six species representing two genera (Chelydra and Macrochelys); this family is restricted to North and South America. Members of this family have large heads, powerful jaws, and small plastrons (lower shells) that restrict them from pulling in their heads and limbs for complete protection. They are not great swimmers and prefer to walk on the bottom of freshwater wetlands. Members of genus Chelydra, called “snapping turtles,” range from Canada through the eastern and central United States and south to Ecuador. Members of genus Macrochelys, called “alligator snapping turtles,” occur in southeastern and southern states; they are the largest freshwater turtles in the world.
Turtles and tortoises represent the oldest living group of reptiles on earth. These generally hard-shelled reptiles are known from fossils as far back as the Triassic Period — over 200 million years ago — and have changed very little since they became established.
All turtles and tortoises belong to the Order Testudines, with 341 living species in 14 genera. Most people are familiar with the general characteristics of turtles, and they are seldom confused with other animals. However, few people are aware of the natural history, habitat requirements, population status, or distribution of even the most common species of turtles.