Alligators typically inhabit freshwater environments like slow-moving rivers, swamps, marshes and lakes. They have powerful jaws and a diet consisting of fish, snails, birds, frogs and small mammals. Adult females average 8.2 feet in length while males average 11.2 feet, with some alligators weighing up to 1000 pounds. Alligators have armored bodies with muscular tails and plated skin on their backs.