You might not know it to look at them, but American alligators have quite the elaborate courtship routine that involves noisy bellowing choruses, head-slapping and a sort of prolonged wrestling match preceding a brief coupling. The noise and spectacle of alligator mating season lights up the swamps and marshes of the southeastern United States during the springtime.
TL;DR (Too Long; Didn't Read)
American alligators mate by attracting one another with vocalizations (by both males and females), infrasonic vibrations and head-slapping by the males and courtship nuzzling and wrestling that may last hours.
Finding Each Other
Though adult alligators tend to be generally solitary animals, they do engage in complex mating rituals. When the weather gets warm in the spring, male and female alligators begin looking for mates. They do this by making low bellowing sounds to announce their presence. Males put on extra spectacle by slapping the water with their jaws, lifting their tails high and causing skittering droplets through infrasonic vibration: the so-called "water dance." Like most animals, alligators use scent as well, releasing an odor from their musk glands. Alligators are not monogamous.
Courtship: How Alligators Mate
When alligators find potential mates, they initiate direct courtship by rubbing and pressing each others' snouts and backs. Pressing behavior seems to be particularly important, with alligators submerging their mates in a sort of contest of strength, and even straddling their heads or mounting them while the partner is underwater. This behavior appears to stimulate further courtship. While courtship routines may last hours, copulation itself is very short: usually less than 30 seconds.
Alligator Nests, Eggs, and Hatchlings
A female alligator builds her nest by mounding up mud and vegetation several feet high. After mating, she uses her back legs to make a bowl-shaped depression at the top of the nest mound. She then lays anywhere between 20 to 50 eggs within and covers them with dirt and leaves. The temperature in the nest determines whether the babies develop as males or females. Mother gators stay near their nests for the full incubation period, which lasts around 65 days.
When the young are ready to hatch, they emit calls from inside the eggs. The mother then removes the dirt and vegetation from the top of her mound, and the hatchlings slowly emerge from the eggs. The mother will carry the babies in her mouth to the edge of the water and gently drop them in. The baby alligators form a pod and stay close to each other, and to their mother, for at least a year.