A is for alligator

Tim Iverson

(2/2018) Everglades National Park is the largest subtropical wilderness in the country. Visitors come from all over of the country, and even the world, to explore its 1.5 million acres. One of the most common things visitors ask is, "Where can I see alligators?" The American alligator is synonymous with Florida, and provokes a "Land of the Lost" or dinosaur-esque feeling when you see one. They could be considered a living fossil as alligators have been around for some 200 million years, actually outliving their dinosaur counterparts. Alligators are visually impressive too, as North America’s largest reptile, measuring up to 15 feet, they command your attention. However they weren’t always so revered.

The American alligator can be found throughout the southeastern United States. Alligators primarily live in freshwater swamps, marshes, rivers, and lakes. They can only tolerate saltwater for short periods of time. Although occasionally they are found in brackish water around mangrove swamps, despite the fact that lack the salt-secreting gland found in crocodiles. Alligators burrow dens out of the muck and mud at the bottom of bodies of water. They use these dens for shelter when winter temperatures get too cold or water when conditions get too dry. However, even outside their dens they can tolerate short periods of freezing conditions. During the winter dry season alligators will modify their habitat by further excavating these "alligator holes," which provide a refuge for other animals during dry periods.

Adult male alligators occasionally reach 13 to 15 feet in length. Whereas, females top out at approximately 10 feet. The snout of an alligator is characteristically broad, although the shape can vary slightly among populations and individuals. Juvenile alligators sport bright yellow cross-bands against black skin, which provides excellent camouflage. The yellow banding fades away as the juveniles mature. Juveniles eat a wide variety of small invertebrates, particularly insects, as well as small fish and frogs. The adult diet typically consists of fish, turtles, small mammals, birds, and reptiles, including small alligators. Feeding activity is governed by water temperature. Alligators will stop foraging if the temperature drops below 68 degrees Fahrenheit. The color of adult alligators varies with habitat and can be olive, brown, gray, or nearly black, with a creamy underside. Algae-laden waters produce greener skin, while tannic acid from overhanging trees can produce darker skin.

Females reach sexual maturity at approximately 6 feet in length. Springtime courtship rituals are complex and can last for several hours. Males attract mates by making loud bellowing noises and performing head-slaps against the water. Female alligators choose nest sites above the water level to reduce the chance of flooding, which would kill most eggs within 12 hours of submergence. Once completed nests are about 3.5 feet high and 7 feet wide. Females wil remain near the nest during the incubation period, which averages 60 days. When danger threatens, she will rapidly return to the nest to protect her eggs. The sex of the hatchling depends on the temperature during development. Eggs that incubate at temperatures ranging from 90 to 93 degrees Fahrenheit hatch as males, while those that incubate from 82 to 86 degrees hatch as females. Intermediate temperature ranges yield a mix of both male and female hatchlings.

When an alligator emerges from an egg the hatchling cries out. When the mother hears this she opens up the nest and begins carrying the hatchlings to the water. She carries 8 to 10 hatchlings at a time in her mouth, pulling her tongue down to make a pouch in which they sit. When she gets to the water, she opens her jaws and shakes her head gently from side to side, encouraging the hatchlings to swim out. The juveniles group up in pods that may include hatchlings from other nests and remain close to the mother typically as long as one year, but sometimes for two or even three years. This social system provides protection, during their most vulnerable life stage, from predators such as raccoons, large fish, birds, and even other alligators –mostly large, dominant males. Nearby females respond swiftly to calls from hatchlings facing impending danger. Hatchlings grow rapidly, especially during their first four years, sometimes averaging more than 1 foot of growth for each year of life.

Alligators are an important part of the Everglades ecosystem and are considered a keystone species of the park. The nesting activity of female alligators is important for the creation of peat soil. Several turtle species, such as the Florida Red-Bellied turtle, incubate their eggs inside both active and old/abandoned alligator nests. Water remains in alligator holes throughout the year except during severe drought conditions. As the dry season approaches and water dries up from other areas within the Everglades, the retained water causes alligator holes to become a refuge for a variety of wildlife. Although these animals become easy prey for alligators and other predators, the value of the refuge outweighs the risk. Human conflicts with alligators are uncommon, but can be serious. Education and awareness is the best long-term way to avoid future incidents. Most alligator attacks on humans are attributed to the illegal feeding of alligators, which makes them bolder, less wary of humans, and more likely to attack instead of flee.

Alligator populations dwindled significantly as a result of hunting and habitat loss, causing the American alligator to be placed on the Endangered Species List in 1967, a law that preceded the Endangered Species Act of 1973. However, illegal poaching continued into the 1970’s. Their belly skin was prized for high quality leather. As a result, extinction may have been possible. The number of alligators only rebounded when alligator farms opened, easing the pressure on wild populations. Populations have dramatically improved and alligators were removed the endangered species list in 1987.

As an apex predator and keystone species they help shape the environment and the other creatures that live within it. While visitors may revel in their sight, it’s best to admire from a distance. Alligators are now abundant throughout the state, but especially so within the interior of the Everglades National Park. This perennial millennial has bounced back from near-extinction level populations, signaling success for the 200 million year old prehistoric reptile. Fortunately, their success means we can keep saying, "See ya later, Alligator," for a little while longer.