Not just to zap prey, apparently. From Ed Yong at the Atlantic:
It’s a remote control. It’s a tracking device. It can deliver shocks of up to 600 volts.
But then you did want to stay awake, didn’t you?
You think the electric eel is shocking? You haven’t seen anything yet. In this episode of Animalism hosted by The Atlantic science writer Ed Yong, we investigate the subtle and sinister ways of the electric eel. More.
See also: Bumblebees judge flowers via electric fields