Piranhas all bark and no bite

Rather than aggressive killers, UK research shows piranhas are omnivorous scavengers, eating mainly fish, plants and insects.

"Previously it was thought piranhas shoaled as it enabled them to form a cooperative hunting group. However, we have found that it is primarily a defensive behaviour," Anne Magurran, of Scotland's University of St Andrews, said.

Piranhas face constant attack from predators including river dolphins, caiman - a relative of the crocodile - and bigger fish. "Their cautious behaviour is crucial to avoid being eaten," Magurran added.

Source : The Daily Telegraph

Tags: piranhas, defensive behaviour