A massive swarm of juvenile striped eel catfish moves as one to fend off predators in a stunning display of group defense. A video shot by Marie-Laure Vergne, an instructor at Abyss Dive Center Bali, shows these kids moving across the ocean floor. Their movements are mesmerizing as they undulate in a mass.
The striped eel catfish is highly venomous as an adult and can cause significant pain. However, because they are still growing, the full force of their venom has not yet manifested itself. “The young ones can only produce a mild version of the venom, tingling the fingers of those who put their hands in the school (which we do not recommend! ),” writes the Abyss Dive Center Bali.
With this information, it makes sense that they’re banding together to ensure the safety of the entire group rather than taking on predators alone. They move as one and are a formidable opponent when combined. If you watch the video closely, you’ll notice that the individual fish aren’t static. Instead, as the mass moves forward, they each move up and down, almost like a waterfall of catfish. When the fish hit the sand, their barbed faces resemble tiny feet scurrying along.
Schools of young striped eel catfish can number in the hundreds. They will eventually become more solitary as they grow older. These fish usually keep to themselves or live in groups of up to 20. Their days are spent hiding under ledges and stirring up sand in search of crustaceans, mollusks, and worms. But, in the meantime, they can spend time together with their peers, floating through the water and avoiding anyone who gets in their way.