View to a Kill: Galápagos Sea Lions Team Up to Capture Huge Tuna

In a newly documented behavior, sea lions use teamwork to trap their prey along shorelines

Recently a few fishermen reported seeing a small group of sea lions successfully hunting down full-size yellowfin tuna, herding and trapping them in two tiny coves along remote lava shorelines on separate islands.

Tui De Roy

Join Our Community of Science Lovers!

In the Pacific, off the Galápagos Islands’ coast, a clever ploy leads to a hearty feast. Sea lions cannot typically catch massive yellowfin tuna—which can swim at speeds of around 40 miles per hour. But a few fishermen recently reported a peculiar hunting behavior among the Galápagos dwellers: Using teamwork, the sea lions have been chasing and trapping the tuna in coves along the archipelago’s ragged coast. Photographer Tui De Roy, a Galápagos resident, recently captured this behavior in a series of striking images. The hunting technique was also recently documented on the BBC’s Blue Planet II natural history series.

“I suspect [cooperative foraging] is a lot more common than we think, and there are many more observations that go unreported,” says Dan Costa, an evolutionary biologist at the University of California, Santa Cruz, who had not heard of the behavior before. “Sea lions are very intelligent animals and the prerequisites for social hunting [are] certainly there.”

According to De Roy, the hunt begins when a few sea lions waddle offshore and into the crisp waters around Fernandina and Isabela islands. Some chase the tuna toward coves on the shoreline; others block the fish’s exit back to the open ocean. Trapped between hungry predators and dry land, a few fraught tuna even jump ashore. And what is a feast without uninvited dinner guests? Sharks, frigate birds, pelicans and hawks swoop in for a bite.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Costa suspects sea lion cooperative hunting behavior is similar to that of wolves. When their prey is small, the wolves hunt on their own, he says. But when it is large and can be shared, they hunt in groups. After all, he notes, “In Spanish sea lions are called lobos marinos, or sea wolves!”

The captions in this slide show are De Roy’s eyewitness descriptions, edited for clarity and brevity.

Yasemin Saplakoglu is a staff writer at Live Science, covering health, neuroscience and biology. Her work has appeared in Scientific American, Science and the San Jose Mercury News. She has a bachelor's degree in biomedical engineering from the University of Connecticut and a graduate certificate in science communication from the University of California, Santa Cruz.

More by Yasemin Saplakoglu

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe