Red-bellied Piranha
Pygocentrus nattereri
Quick answer
The red-bellied piranha is a freshwater fish of South America's Amazon basin, known for its sharp, interlocking teeth and reddish belly. It usually grows 20 to 35 cm (8 to 14 in) long and lives in shoals in rivers and floodplains, eating fish, insects, and plant matter as well as scavenging. Despite a fearsome reputation, attacks on people are rare; piranhas live around 10 years.
Red-bellied Piranha facts at a glance
| Scientific name | Pygocentrus nattereri |
|---|---|
| Diet | Omnivore (mostly carnivorous) |
| Habitat | Amazon rivers, streams, and floodplains |
| Lifespan | About 10 years |
| Length | 20–35 cm (8–14 in) |
| Top speed | Fast in short bursts |
| Conservation status | Least Concern (IUCN) |
| Kingdom | Animalia |
|---|---|
| Phylum | Chordata |
| Class | Actinopterygii |
| Order | Characiformes |
| Family | Serrasalmidae |
| Genus | Pygocentrus |
Where it lives
Rivers, streams, and floodplains of the Amazon basin and other river systems of tropical South America.
Behavior and shoaling
Red-bellied piranhas live in groups called shoals, which is thought to offer protection from predators such as larger fish, caimans, and birds rather than being a hunting strategy. They communicate with barking and croaking sounds, especially when threatened or competing for food. Despite their reputation, they are often skittish and can be more prey than predator in the rivers they inhabit.
Diet and feeding
Piranhas are omnivores that lean toward a carnivorous diet of fish, insects, crustaceans, and worms, and they also eat seeds, fruit, and plant matter. They are important scavengers, cleaning up dead and dying animals in the water. Their sharp, triangular teeth and strong jaws allow them to bite off pieces of flesh quickly.
Habitat and range
The red-bellied piranha lives in the Amazon basin and other river systems of tropical South America, including parts of Brazil, Venezuela, and Argentina. It favors slow-moving rivers, streams, oxbow lakes, and flooded forests. During the dry season, falling water levels can concentrate piranhas in shrinking pools.
Reputation and human interaction
Piranhas are often portrayed as bloodthirsty, but mass feeding frenzies usually occur only when food is scarce or fish are crowded into low water. Bites on humans do happen, typically on the feet or hands in shallow water, but serious attacks are rare. They are also a common food fish for local people and a popular aquarium species.
Frequently asked questions about the Red-bellied Piranha
Do piranhas attack humans?
Attacks on people are uncommon and rarely serious, usually limited to nips on the feet or hands in shallow water. Most reported bites happen when fish are stressed, crowded, or food is scarce.
What do piranhas eat?
Red-bellied piranhas are omnivores that mostly eat fish, insects, and crustaceans, and they also scavenge dead animals and consume seeds, fruit, and plants.
How big do piranhas get?
Red-bellied piranhas usually grow 20 to 35 cm (8 to 14 in) long. They are powerful for their size but are not large fish.
Why do piranhas live in groups?
Piranhas form shoals mainly for protection from predators such as larger fish, caimans, and birds, rather than to hunt cooperatively.
Are piranhas dangerous as pets?
Piranhas can bite and should be handled carefully, but with a suitable tank they are kept as aquarium fish. Releasing them into non-native waters is illegal in many places.
How long do piranhas live?
Red-bellied piranhas typically live around 10 years, and they can reach a similar age in well-maintained aquariums.
