A filmmaker visiting the Los Islotes sea lion colony north of La Paz, Mexico, was expecting to dive with hundreds of friendly sea lions but was surprised by a staggering sight: sea lions attacking a pufferfish.
“I’ve dived all over the world, and I’ve spent years diving in Baja California Sur, but this day I saw something I had never seen before,” says ocean filmmaker and dive expedition leader Matthew David Kaplan. “This one day, we saw something darker.”
He’d been observing the colony in the Espíritu Santo Marine Park when he noticed an unusual – and somewhat chilling – behaviour.
“A sea lion was abusing and mauling a beautiful black guineafowl pufferfish,” says Kaplan. “It would grab the pufferfish, pull it up toward the surface, and bite it. Then the terrified pufferfish would frantically swim down trying to escape, only to be pulled back up again.”
Several sea lions were ganging up on the poor little fish, which was doing everything it could to escape. “And just as the pufferfish was about to find refuge under a rock, they would pull it by the tail and it would start over again,” he says. “I’ve never seen anything like it.”
To try to stop itself getting eaten, the pufferfish had ballooned itself into a large ball – they do this by pumping water or air into their stomachs as a means of self-defence. But that didn’t stop the determined sea lions.
The reason the sea lions were beating up on this pufferfish might surprise you. “They’re basically doing it to get high,” says Kaplan. “Apparently there’s a toxin in the pufferfish that gives them a narcotic effect.”
- Meet 9 animals that enjoy getting high
- Scientists put tiny cameras on a load of Aussie sea lions – what they found was mesmerising
Another way pufferfish defend themselves from predators is through the neurotoxin tetrodotoxin (TTX) present in their bodies. It’s the same toxic substance that makes the blue-ringed octopus so dangerous. But sea lions may have learned that small doses give them a pleasant buzz.
“In tiny exposure it may create a strange, dulled, disoriented sensation,” says Kaplan, “which could be part of why animals mess with them.”
Kaplan tried to intervene, escorting the fish to the safety of the rocks. “Most people say don’t ever interfere with nature but I just couldn’t help myself,” he says. “I thought I had helped it but just as I left, it got pulled out again.”
Eventually, the divers had to return to the surface, reluctantly leaving the pufferfish behind. “We have no idea how much longer the sea lions kept at it,” he says. “Unbelievable to witness.”
Image and video credit: Ocean filmmaker and dive expedition leader Matthew David Kaplan
More dramatic wildlife stories from around the world
- Drone captures Greenland ice tearing open to reveal humungous animal beneath
- This is the biggest snake den on the planet – 100,000 crammed into a small cavern
- Orcas are now hunting whale sharks – and they're doing it in an astonishing way
- In the dead of the night, this diver saw a bizarre thing scuttling out of the darkness
