American Alligator

Range and Habitat

Alligators range from central Texas eastward to North Carolina. Louisiana and Florida have the largest alligator populations—there are more than one million wild alligators in each state. Although alligators can be found in ponds, lakes, canals, rivers, swamps, and bayous in Louisiana, they are most common in our coastal marshes. Of the almost 4.5 million acres of alligator habitat available in Louisiana, coastal marshes account for more than 3 million, followed by cypress-tupelo swamp (750,600 acres), Atchafalaya Basin swamp (207,000 acres), and lakes (32,105 acres).

Mature males and non-breeding females tend to stay in deep water habitats. Nesting females, hatchlings, and small juveniles are commonly found in shallow marsh habitats with thick emergent vegetation.

Behavior

Reptiles are cold-blooded animals, which means that their body temperature is regulated by the temperature of the environment around them. This is why alligators are often seen regulating their body temperature by basking in the sun. Because alligators are cold-blooded, in cooler portions of their range their metabolism may slow down during the cool winter months to the point that they can no longer catch or digest food efficiently. As a result, they may enter underground holes and remain dormant until warmer conditions return.

Size, growth rates, and lifespan

Alligators are about 8 to 9 inches in length when they hatch from eggs. Their growth rates depend on several factors including their habitat, sex, size, and age. Growth rates slow as alligators get older. Male alligators grow faster and larger than females. Females rarely exceed 9 feet in length and large females can weigh more than 200 pounds. Males rarely exceed 13 feet in length and large males can weigh well over 500 pounds.

Alligators in the wild can live up to 70 years; some in captivity may live even longer.

Reproduction

Alligators mate in April and May, beginning a life cycle that evolved from prehistoric times. A giant male or "bull" alligator begins bellowing in the spring to attract females and warn other suitors to stay away. For two months, male alligators fight to see who gets to court the female or "sow" alligators. Alligators can be vicious fighters during mating season. They will eat almost anything, including each other; they bite and fight to eat, court, defend, or protect their territory. The winners are sometimes badly scarred—it is not uncommon to see alligators with missing legs, bobtails, or blinded eyes. (Note that they still mostly shy away from humans unless they are fed or harassed.)

In June or July, after they mate, females select nesting sites, usually near isolated ponds in interior marsh habitats, and build nests by pulling marsh vegetation into a mound. These nests are several feet high and up to 10 feet across. They make a cavity in the nest and lay up to 60 eggs (the average clutch is about 35 eggs). They then cover the cavity with vegetation from the nest. As the vegetation decays, it creates heat to incubate the eggs—the temperature of the nest determines the sex of the hatchlings with warmer temperatures favoring males. However, very high temperatures produce females; high incubation temperatures also lead to more mortality.

Females remain near the nest as the eggs incubate. Eggs hatch in about 65 to 70 days. The hatchling develops an "egg tooth" on top of its snout to slit open the egg. It begins to chirp even before it has emerged from the egg. Soon the whole clutch is chirping to signal to the mother alligator that it's time to leave the nest. If an egg doesn't hatch properly, the female may gently break the egg in her massive jaws to help the hatchling get out and may even carry some hatchlings to the water in her mouth. The young alligators remain in the water for the next six months under the watchful and protective eye of the female, who will defend their young from predators or intruders. In fact, the young may stay near the nest site for a couple of years.

A lot of other animals, particularly herons, egrets, and even largemouth bass, eat alligator hatchlings, and mortality of young hatchlings is high due to both predators and natural mortality. Only some hatchlings will survive and grow to become breeders at approximately 6 feet. Once they’re adults, the only real threat to an alligator is another alligator or humans.

Feeding

Hatchlings begin snapping up insects soon after birth. They graduate to a diet of crawfish, small fish, and frogs over time. As they grow, their diet changes to include larger animals such as crabs, larger fish, frogs, and small birds. As alligators reach adulthood and continue to grow, their diet continues to expand and can include even larger animals such as muskrats, nutria, beavers, raccoons, large birds and fish, snakes, turtles, and deer—basically anything that can't eat them first.

Alligators will hunt anytime but particularly at night as they are well adapted with a good sense of smell and vision in the darkness.

Population Status

Once threatened by unregulated hunting, alligator populations are now fully recovered thanks to extensive research, careful management, and responsible stewardship of this valuable resource and its habitat. There are now alligator hunting seasons in many states, and populations are managed for sustainability. Louisiana has implemented a successful alligator management program that includes controlled wild harvest and egg collection for commercial alligator production. Alligator skin is tanned for exotic leather products and the meat is sold for consumption. Alligator farms, as well as wild-caught alligators, supply these industries.

More Information/References

Alligator: Hunting, Research, and Management