"Watch a cat when it enters a room for the first time. It searches and smells about, it is not quiet for a moment, it trusts nothing until it has examined and made acquaintance with everything."

- Jean Jacques Rousseau

The Piranha Fish

Pirahna Fish

The Piranha, also called caribe or piraya is a razor-toothed, carnivorous fish of South American rivers and lakes, with a somewhat exaggerated reputation for ferocity. Although the carnivorous species are the best known, most species are herbivorous.

Most species of piranha never grow larger than 60 cm (2 feet) long. Colours vary from silvery with orange undersides to almost completely black. These common fishes have deep bodies, saw-edged bellies, and large.Carnivorous species have blunt heads and powerful jaws with sharp, wedge-shaped teeth that mesh like cutting shears and enable the fishes to cut the flesh from prey, which consists mostly of other fishes but also includes amphibians, birds, and mammals.
Carnivorous piranhas associate in large schools and are attracted by commotion and the scent of blood. Once aroused, they can quickly reduce a large mammal to a skeleton, although such incidents are rare. About four species are considered dangerous. Piranhas are also scavengers, and they are considered fine food fishes.

Found from northern Argentina to Colombia, piranhas are most diverse in the Amazon River, where 20 different species are found.
The most infamous is the red belly piranha (Serrasalmus nattereri), with the strongest jaws and sharpest teeth of all. Especially during low water, this species hunts in groups that can number more than 100. Several groups can converge in a feeding frenzy if a large animal is attacked, although this is rare.

Red belly piranhas prefer prey that is only slightly larger than themselves or smaller. Generally a group of red bellied piranhas spreads out to look for prey. When located, the attacking scout signals the others. This is probably done acoustically, as red belly piranhas have excellent hearing. Everyone in the group rushes in to take a bite and then swims away to make way for the others. Most species of piranhas, however, never kill large animals, and piranha attacks on people are rare. Although piranhas are attracted to the smell of blood, most scavenge more than they kill. Some 12 species called wimple piranhas (genus Catoprion) survive solely on morsels nipped from the fins and scales of other fishes, which then swim free to heal completely.

"piranha." Encyclopædia Britannica from Encyclopædia Britannica 2007 Ultimate Reference Suite. (2007).