However, researchers found that piranha most likely group together as a defense against such predators as river dolphins, caimans and bigger fish, and not to engage in feeding-frenzies.

• 然而研究人员发现食人鱼在防卫如河豚、凯门鳄及其它大个的鱼这样的掠食者时才会集结在一起，并且不会疯狂摄取食物。