Although crocodilians - as alligator and crocodiles are called- inspire fear and fascination in us, few people know they are an important part of the ecology of Florida's wetlands.

Two crocodilians are native to the United States, the American alligator, found only in the southeastern part of the country, is restrained by cold temperatures and the distribution of wetlands. The American crocodile is even more sensitive to cold and its range, which includes the southern tip of Florida, is tropical.

Alligators and crocodiles are protected by state and federal laws; the alligator is listed as threatened and the crocodile as endangered under the federal Endangered Species Act.

Crocodilians are relics of the great Age of Reptiles in which, for 100 million years, these primitive-looking creatures ruled the earth. Today, only 21 crocodilian species remain, and many of these are in danger of extinction from conflicts with man. Of all the reptiles, crocodilians are the largest and have the most complex behavior, including elaborate courtship displays, nest-building behavior and social rituals.

An estimated 10 million alligators were killed for their skins between 1870 and 1970 when hunting was controlled. While the alligator has benefitted from legal protection and is now abundant in may areas, habitat loss and conflicts over water management continue to threaten the alligator and many other wildlife species in Florida.

Crocodiles have always been rare in Florida, but alligators once dominated life in the state's freshwater wetlands. By building and maintaining ponds and nests, alligators create habitat that supports a rich array of life in the wetlands. The decline of the alligator through most of this century has disrupted this relationship and altered the ecology of Florida's freshwater wetlands.

American crocodiles are rare in Florida and very secretive, so if you see a crocodilian in the wild, its likely to be an alligator. Alligators are usually found in fresh water, have broad snouts, and are darkly colored. Crocodiles prefer coastal, brackish or salt-water habitats, have more tapered and triangular-shaped snouts and are greyish-green in color.

The alligator is a large lizard-shaped reptile with a rough scaly hide and a long, muscular tail. Young alligators have bright stripes and yellow blotches but as they mature, their skin becomes dark.

In the swamps and marshes of Florida, the typical home of the alligator is an alligator pond or "gator hole." These depressions hold water during the dry season. Without a resident alligator the ponds fill with mud and vegetation within a few years.

Alligators eat anything they can catch: fish, turtles, racoons, birds, dead animals and even other alligators. An alligator can float motionless in the water with only its eyes and nostrils exposed, waiting for a meal. The powerful jaws can easily crush the shell of a turtle or the bones of an animal.

Alligators have a complex social hierarchy that varies with sex, age, and habitat conditions. In the Everglades, large males tend to stay in open water, while females live in small ponds. Males move from pond to pond during the breeding season to mate.

Alligator courtship begins as the weather warms in early spring and features a varied sequence of behaviors including bellowing, head slapping, snout touching and bubble blowing. The bellowing of courting alligators is a familiar sound in the swamps in spring.

Female alligators construct elaborate nests of compacted vegetation. The eggs are incubated by the heat from rotting vegetation. Twenty to 50 eggs incubate for about two months and the mother may stay nearby to ward off predators. Shortly before hatching, baby alligators begin to emit a high-pitched barking sound. The mother responds by opening the nest and sometimes helping her young to hatch by carefully cracking the eggshells in her mouth. Young alligators may stay with their mother for a few days to several months. Sometimes they bask on their mother's head and back.

The ponds, dens, nests, and trails of alligators have shaped and contoured the landscape of Florida's wetlands. The compacted vegetation left in old nest mounds and pond banks forms a peat resistant to decay and fire. In fact, much of the high ground in the Everglades can be traced to the work of the alligators.

Adult American crocodiles are gray-green, dark olive, or gray-brown across the back. Once found from Lake Worth to the waters in and around Florida Bay, most crocodiles now nest in the Crocodile Lake National Wildlife Refuge on Key Largo, in the Everglades, and on the berms of the cooling canals of Florida Power & Light's Turkey Point Plant.

Crocodiles are shy and reclusive animals, easily disturbed by human activity. They prefer the quiet waters of coastal mangrove swamps where they are protected from onshore winds. Some crocodiles dig burrows 10 to 30 feet into creek banks with entrances at or below the waterline. Nests, which are simpler than those of alligators, are built on marl banks or sand/shell beaches. Clutches of 8 to 80 eggs incubate for about 85 days. As with alligators, the mother crocodile digs open her nest and helps her young hatch.

Crocodiles feed at night on fish and other aquatic animals in creeks, open water and deep channels.

Despite protection, the number of crocodiles in south Florida has been slow to increase; however, the present population seems to have stabilized. Habitat loss and changes in salinity and water levels in Florida Bay as a result of extensive drainage programs may be a factor limiting populations.

Alligators have been known to injure or kill people and pets. Most attacks occur in the water, suggesting victims are mistaken for prey. The Florida Fish and Wildlife Conservation Commission receives thousands of nuisance complaints a year. Many of these alligators must be killed because there few places where they can be relocated. Because of the shy and reclusive nature of crocodiles, they generally do not pose a problem for man.

Carrie's note: As of September 15, 2005, Florida Fish and Wildlife Commission has vowed to crack down on people who feed alligators. This exposes the alligator to people, thus losing it's natural fear of man and making it more likely to attack humans. Feeding alligators is a misdeamor and there is a fine involved. NEVER under ANY circumstances feed an alligator, or any other wild animal. They are quite self-sufficient. They need to have that natural instinct to fear us if they are going to survive. Too many times I have heard of an alligator that has been fed attack a human, and then Fish and Wildlife will scour the area for 'gators in like size and kill them to protect us. This shouldn't have to happen to them. They have their place in our environment and deserve to live the same as we do.

As a very visible member of the wetland community, the alligator is a barometer of how well wetlands are faring. Now that the alligator and the crocodile have been saved from extinction, many difficult decisions regarding water management and land development need to be made concerning the future of these species and their habitat.

Alligator and crocodile facts