Animal Data > Red Bellied Piranha

(Serrasalmus nattereri)

Piranhas are actually friendly so are naturally shoaling fish and are found in fast-moving streams. They often hunt in packs which make it easier for them to subdue their larger prey, but generally the ferocity of the piranha has been overrated. They are aggressive but will usually only attack if they smell blood in water so as a result they have a very keen sense of smell.

The red-bellied piranha has small but sharp, triangular teeth set in powerful jaws. The teeth interlock when the fish’s mouth is closed, enabling it to slice off chucks of flesh. The blunt snout and under slung lower jaw also help it attack, allowing it to bite with an unusual force. Their teeth are located perfectly for biting anything. They generally eat fish smaller than themselves but have been known, however to reduce a large animal such as a tapir to a skeleton in minutes!

They generally feed at dawn and dusk, lurking and then dashing at their prey. In the wild their diet consists mostly of fish, bugs, and any other animal that can be taken in water.

The female will lay up to 1000 eggs which hatch after about 9-10 days. The male remains with the eggs while the female joins the group again. At this time he is very aggressive. He circles the eggs, fanning them with oxygenated water. When they hatch they do not have their characteristic red bellies. These will start to develop at about 3 months of age. A fully grown piranha will reach about 11 inches.

There are over 500 species of Piranha most of which are vegetarian, feeding mainly on fruit!

Main Features

Body is tall and very compressed laterally and a fat (adipose) fin is present. Most of the body is a bluish grey and the belly is strikingly red. The sides (flanks) are pale brown to olive with numerous shiny spots but coloration varies. The dorsal and caudal fins are dark and the anal fin usually has a broad black border.

In Captivity

The red-bellied piranha is generally hard to keep in captivity and in certain states of North America it is illegal to keep them. This is to prevent irresponsible hobbyists releasing specimens as they can multiply and prey on other fish. Their care is difficult and they need special conditions in the tank; 80 degrees, pH 6.5-7 and a tank of about 75 gallons+ You must also be prepared to feed them meat and seafood!

There are around 20 individuals at Marwell which came from Maidenhead Aquatics in 2002 and they were all captive bred. It is almost impossible to sex them. They are fed every other day on cockles and mussels but occasionally they get a mouse or whole herring!