Both the Alligator Snapping Turtle (Macrochelys temminckii) and Common Snapping Turtle (Chelydra serpentina) live their lives almost entirely in freshwater, though they can be found in brackish water. They might both be turtles, but there are some significant differences between these species. The most significantly obvious is the top shell or carapace structure. In the Alligator Snapping species, the carapace has three distinct ridges and spiking all across the shell. The Common Snapper has a much smoother carapace with no ridging or spiking. Both species have similar colors and markings with varying shades of browns, greys, and creams.


Main Differences Between Alligator Snapping Turtle vs Common Snapping Turtle
- Appearance: The Alligator Snapping Turtle has a ridged and spiked top shell, while the Common Snapping Turtle has a smooth top shell.
- Size: While they are both considered large freshwater turtles, the Alligator Snapping Turtle is considered the largest freshwater turtle species, growing up to 30 inches and weighing up to 250 pounds.
- Habitat: These species both utilize freshwater ways and environments, but their ranges vary. The Alligator Snapping Turtle is found within the southeastern United States, and the Common Snapping Turtle is found from southern Canada to the Midwest and eastern states.
- Diet: Both species have similar diets and are ambush hunters; the main difference is that the Alligator Snapping Turtle has a small worm-like appendage in its mouth that it uses to lure prey into snapping range.
- Age: Data shows that both species live an average of 30 years in the wild, but the Common Snapping Turtle has been shown to live over 100 years in captivity.
- Reproduction: The main difference in reproduction for these species is timing. The Alligator Snapping Turtle breeds in the spring, and the Common Snapping Turtle breeds from Spring through Fall.
We will explore the differences and details about both species below.
Alligator Snapping Turtle
Just like any other turtle, the Alligator Snapper is built with a shell that protects the soft body of the animal. This species is sometimes compared to a dinosaur in looks due to its spiked shell, beak-like mouth, and nodule-laden skin.
Appearance
The Alligator Snapping Turtle is considered the largest freshwater turtle species. With its carapace that has three distinct ridges running along the entire span from head to tail, this species is often said to look prehistoric. Their long muscular tails are covered in smooth bumps. Their large head and beak-like mouth give them powerful jaws, making them easy to identify. Males grow up to 30 inches in carapace length and can weigh up to 250 pounds. Females are smaller, growing up to 20 inches and weighing up to 60 pounds.

Habitat
The Alligator Snapping Turtle is only found in the United States, being found in northern Florida, spanning from there into eastern Texas and parts of Iowa. This species of turtle spends almost all of its time in the water, except for females that come on land to dig nests and lay eggs. This turtle species can hold its breath for close to an hour, staying so still in the water that algae often grows on their bodies and shells. They prefer habitats of rivers, lakes, canals, swamps, and wetlands. They prefer to spend their time in deeper water where they can hide in snags and fallen submerged logs.
Diet
The Alligator Snapping Turtle has a very unique way of catching prey items for food. The tongue of this turtle has a worm-like appendage that can be wiggled like a fishing lure independent of the tongue. The turtle lays still in the deep water with its mouth open, attracting passing prey into its mouth. These Snappers are ambush hunters and generally carnivorous, eating fish, insects, snails, crayfish, mussels, snakes, birds, small mammals, and sometimes vegetation.

Age
This species has a lifespan in the wild of between 11 and 45 years, but captive individuals have been reported to have lived up to 70 years of age.

Reproduction
Much like the rest of their lives, courtship, and breeding take place in the water during the Spring. The females will haul out of the water to dig and lay their eggs, promptly returning back to the water. Clutches of eggs average 30 in number and will begin to hatch after about 100 days. These species do not reach sexual maturity until 11 to 13 years.

Common Snapping Turtle
The Common Snapping Turtle, much like the Alligator Snapper, has a powerful mouth and bite but also has a snakelike neck that they can use to be fiercely combative, especially out of the water. They, too, have a hard shell that protects their soft body.
Appearance
The Common Snapping Turtle is another large freshwater turtle native to North America, with a smooth carapace colored from black to dark brown. Their tails are as long as their carapace, and the dorsal (top side) is ridged with large projections or keels, giving a unique saw-tooth look. The plastron (bottom shell) is quite small and does not provide full cover for its soft undersides. This species is smaller than the Alligator Snapper but is still considered a large turtle. They grow up to 19 inches in length of carapace and can weigh up to 45 pounds or more. On average, males are larger than females.

Habitat
The Common Snapping Turtle is also considered to be almost exclusively aquatic. This species has a wide range from Canada, throughout the Eastern U.S., to the Gulf of Mexico. They inhabit areas of slow-moving water with soft bottoms so they can burrow and hide. This species can be found in streams, creeks, bogs, marshes, rivers, ponds, and even some brackish environments. The Common Snapper can rest so long, and still that moss and algae from the aquatic habitats can be found growing on their carapace. Much like the Alligator Snapper, the Common Snapper spends the majority of its time submerged in the water, except for females coming onto land to nest and lay eggs.

Diet
As true omnivores, the Common Snapping Turtle eats many items, not limited to but including insects, frogs, small mammals, small turtles and other reptiles, birds, and even carrion. In this species, vegetation makes up about a third of their diet. As they grow, the turtles will forage, but once of larger size, they lay in wait either in the deep water or just below the surface to ambush prey in their environment.
Age
This species has a lifespan in the wild of 30 years and is believed to live over 100 years in captivity.
Reproduction
Much like their counterparts, their entire life cycle takes place in the water, including courtship and breeding from April through November. Once the female lays the eggs, she returns to the water, leaving the nest alone. Egg clutches include 20 to 40 eggs that incubate for 80 to 90 days. Sexual maturity happens when the carapace reaches eight inches.

FAQs
How strong is a Snapping Turtle bite?
The Alligator Snapping Turtle has a bite force of 158 Newtons
The Common Snapping Turtle has a bite force of 209 Newtons.
The average human has a bite force of 1,300 Newtons.
Despite the large difference between the Snapper and human bite force, the Turtles can still break bones with their bite.
How do Snapping Turtles breathe under the water?
While both species of Snapping Turtles can stay underwater for one to three hours before coming up for air, they also can survive underwater for months at a time with cloacal respiration. The metabolism of the Snapping Turtle slows down by 90% during winter allowing the animal to absorb oxygen through their cloaca (an opening through which they expel its waste). This allows them to stay submerged throughout the winter months, even when there may be ice on the surface.
Do Snapping Turtles have predators?
Both species, Alligator and Common Snapping Turtles, are highly vulnerable during the egg and hatchling stages of life. It is not uncommon for the eggs or hatchlings to be eaten by the following but not limited to raccoons, skunks, snakes, crows, herons, alligators, and other turtles. Whether raiding the nest for eggs or taking adults for their meat, or harvesting specimens from the wild for pets, humans are the main predator of both species.
Why is it called an Alligator Snapping Turtle?
The Alligator Snapping Turtle has a reputation for its strong bite and its ridged and spiky appearance, much like an alligator.
How long can a Snapping Turtle hold its breath?
The Alligator Snapping Turtle can hold its breath for about an hour.
The Common Snapping Turtle can hold its breath for up to 3 hours.
Can I have a Snapping Turtle as a pet?
Some states allow you keep to keep either species, but others make it unlawful due to their conservation status, while some states encourage the hunting of certain species due to their invasiveness. It is important to check your local laws before deciding to keep any wild animal as a pet.