(Newer)
A new study has revealed a big surprise about electric eels – they hunt in packs. Before the study conducted in Ecology and evolution, scientists thought the creatures were hunting on their own, chopping fish and then eating alone, reports the BBC. But in a Brazilian river in the Amazon, researchers have for the first time documented a pack of Volta’s electric eels (technically, knife fish) that work together to correlate and kill small fish, according to Live Science. The eels gather in groups of about 100, then surround tetravises and herd them in shallow water. It closes smaller groups of eels and chops the tetra, sometimes with enough force to make them fly out of the water. The demobilized tetra is then easy to choose. Although mammals hunt regularly, their use is rare among fish, CNET explains. The number of fish species that do this is thought to be around 10.
‘This is an extraordinary discovery,’ says senior study author C. David de Santana, per Smithsonian Magazine. “Such a thing has never been documented in electric eels.” Volta’s electric eel grows to about 8 feet long and can deliver a shock of 860 volts, the strongest of any animal on earth. If ten of them were to go down at the same time, that would be enough to power 100 light bulbs, Santana says. And yes, he himself was hacked and described it as strong enough to cause numbness in his arms. “It’s a very strong discharge, but the duration is very short,” he says. Researchers have documented the hunting strategy several times on the Iriri River in Brazil, although they are not sure how widespread it is among eels elsewhere. They started a civil science project to gather more information. (Read more stories about electric eel.)