American Alligator

The American Alligator has a large, slightly rounded body, with thick limbs, a broad head, and a very powerful tail. They generally have an olive, brown, gray or nearly black color with a creamy white underside. Algae-laden waters produce greener skin, while tannic acid from overhanging trees can often produce darker skin.

Image credit: © Gerald and Buff Corsi, California Academy of Sciences