These predatory fish are very abundant throughout the Amazon basin. Fortunately, their “biting” reputation is also very overstated. Under normal conditions, piranha pose little threat to humans, much preferring a diet of fish. However, when water levels drop and their normal food supply is diminished,piranha will attack “other” sources of protein.

Indigenous people in some regions along the Brazilian Amazon catch some fish by using a toxin found ina local plant to temporarily paralyze the fish. This same toxin is used to control the piranha population when it gets high enough to deplete other fish species.