Social predation in electric eels

Abstract

Social predation, when groups of predators coordinate actions to find and capture prey, is a common tactic among mammals but comparatively rare in fishes. We report the unexpected social predation by electric eels, an otherwise solitary predator in the Amazon rainforest. Observations made in different years and recorded on video show electric eels herding, encircling shoals of small nektonic fishes, and launching joint predatory high-voltage strikes on the prey ball. These findings challenge the hypothesis that electric eels may have a single foraging strategy, and extend our knowledge on social predation to an organism that employs high-voltage discharge for hunting, thereby offering a novel perspective for studies on the evolutionary interplay between predatory and escape tactics.