Scientific Classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Characiformes
Family: Serrasalmidae
Genus: Pygocentrus
Species: P. nattereri
Conservation Status
Red-bellied piranhas are the smallest species of piranha usually growing 14 inches long and weighing about 8.5 pounds. As their name suggests, they have a reddish stomach with females having a deeper red color. The rest of the red-bellied piranha is grey and silver-flecked with a dark dorsal and tail fin, and orange to red pectoral and pelvic fin
The red-bellied piranha is native to South America and can be found in different bodies of waters in Paraguay, Brazil, the Amazon, and more. Not only do they reside in major rivers and lakes, but they also enjoy warm freshwater floodplains and flooded forests.
If there are red-bellied piranhas outside of South America, it is because they were taken as pets, which is legal as long as they are not released possibly becoming invasive
Despite common beliefs, piranhas are not simply carnivores as they will also eat plants and whatever else they can find since they are scavengers and foragers.
The typical diet of a red-bellied piranha is fish, crustaceans, worms, plants, and more. Since they travel in large groups, their bigger prey may include capybaras or egrets.
Red-bellied piranhas will reproduce twice a year tied to water levels, temperature, and other environmental conditions. Females will lay several thousand eggs near water plants for males to fertilize. Unlike other fish, piranhas will circle their nest to intimidate predators from eating their eggs but are passive if anyone approaches. After 2-3 days, the eggs hatch and the juveniles will hide in the plants until they are large enough to hunt food.
Part of the red-bellied piranha’s fearsome reputation is the fact that they are usually found travelling in large groups, or shoals. This is because piranhas are not apex predators and by examining older fish on the inside of shoals with younger fish on the outside, scientists concluded that red-bellied piranhas travel in them for safety. Also, the piranhas seemed more at ease when journeying in large shoals even when faced with a predator.