The largest predator in the Amazon, Melanosuchus niger is capable of growing to more than 6 m. It resembles the American Alligator but is biologically more closely related to the other caimans. This may be due to similar habitats.
Diets can vary depending on the age, size, habitat, and available prey.
Mean prey size is usually positively correlated to caiman size. Fish, such as piranhas and catfish, account for a large part of the adult Black Caiman's diet, as do molluscs. Young individuals tend to eat insects, crustaceans, and other invertebrates, but many of these are usually replaced in the diet as the caiman matures. Reproduction Good information concerning the Black Caiman's breeding habits is not plentiful. In the dry season, which runs from September through December, the female builds a nest mound, using the hind feet to dig an egg chamber.