Why are these emperor penguin chicks jumping from a 50-foot cliff?

Like a group of teenagers crowding at the top of a cliff, waiting to see if someone will be brave enough to jump into the lake first, hundreds of months-old emperor penguins gather at the top of an Antarctic ice shelf towering roughly 50 feet above the sea. 

Motivated by hunger, the fledglings peer over the edge, as if considering whether they might survive a polar plunge from such a height.

Then one bird goes for it. 

Some of the onlookers crane their necks to watch it plummet and splash into the icy water below. Seconds later, the chick surfaces and swims away—off to fill its belly with fresh fish, krill, and squid. Gradually, other fledglings follow, tumbling and flapping wings built for traversing water, not air.

Filmmakers producing a documentary series called Secrets of the Penguins, which will debut on Earth Day 2025 on National Geographic and Disney+, captured the extraordinarily rare scene by drone in January in Atka Bay, on the edge of the Weddell Sea in West Antarctica. It’s the first video footage of emperor penguin chicks leaping from such a high cliff, according to scientists.

As climate change melts sea ice in Antarctica, more emperor penguin chicks are breeding on the permanent ice shelf—forcing them to jump from higher heights into the ocean. 

“I cannot believe they caught it on film,” says Michelle LaRue, a conservation biologist based at the University of Canterbury in Christchurch, New Zealand. LaRue, who did not witness the jump, had visited Atka Bay to consult on the film crew’s third year of documenting emperor penguin behavior, from egg laying to chick fledging.

Ordinarily, emperor penguins nest on free-floating sea ice that thaws and blows away each year, not on the ice shelf, which is firmly attached to the land. But lately, some colonies have been nesting on the shelf. Scientists theorize that the shift could be related to increasingly earlier seasonal thawing of the sea ice caused by climate change.

At about five months old, emperor penguin chicks began to shed their down and grow their adult feathers, preparing for a life spent partially at sea. 

The International Union for Conservation of Nature lists the world emperor penguin population, estimated to be about 500,000 birds, as near threatened due in large part to how climate change is impacting its icy realm. (Read more about the bleak future for emperor penguins.)

In early January 2024, in the final weeks before the sea ice broke up at the end of the Southern Hemisphere summer, filmmakers spotted a group of chicks that LaRue thinks were likely raised on the ice shelf waddling north toward the cliff. Curious about where they were headed, the filmmakers dispatched a drone for a bird’s-eye view. Gradually, more chicks joined the dawdling group, growing in numbers until there were a couple hundred standing at the top of the bluff.

‘I’m gonna have to go’

Gerald Kooyman, a research physiologist who has spent more than five decades studying emperor penguins in Antarctica, says he has only seen such an event once—more than 30 years ago.

“Drifting snow had formed a gently sloping ramp from the sea ice onto a grounded iceberg, and a flock of departing chicks had marched up the ramp onto the berg,” Kooyman writes in his book Journeys with Emperors, published in November 2023.

“They were stopped by a 20-meter [roughly 67-foot] cliff over a sea that was sometimes open water and other times crowded with ice floes.” Over the course of a couple days, almost 2,000 chicks assembled at the ledge.

“Finally, they started walking off the cliff,” writes Kooyman, an emeritus professor with the Center for Marine Biotechnology and Biomedicine at the Scripps Institution of Oceanography in California.

“Not jumping or leaping, just stepping out and falling head over heels, sometimes doing two flips before hitting the water with a resounding plop.” (See more incredible photos of emperor penguins.)

Most of the fledglings survived the jump into the icy waters. The chick on the left that fell into a crevasse used its beak to climb out and leap the rest of the way.

This phenomenon is rare, say scientists who monitor penguins from satellites in space. Peter Fretwell, a British Antarctic Survey scientist who has studied satellite imagery of the Atka Bay emperor colony for several years, occasionally sees penguin tracks going north toward that cliff. He theorizes that the chicks in January may have followed one or two vagrant adults that “went the wrong way, basically.”

Juvenile emperors usually fledge from the sea ice, hopping just a couple feet into the ocean. But these fledglings found themselves in a tricky location for entering the water while likely feeling extremely hungry, the scientists say. Their parents had already gone to sea, sending the message that it’s time for them to fish for themselves, and the chicks had been sitting tight waiting for their sleek, waterproof adult feathers to grow in, replacing their down.

“When they get to this cliff face, they’re like, ‘Alright, I see the ocean and I need to get in there,’” LaRue says. “This does not look like a fun jump, but I guess I’m gonna have to go.”

Resilient birds

While the scientists do not think the cliff-jumping incident was directly related to climate change warming Antarctica, Fretwell says the continuing decline of sea ice on the continent may force more emperors to breed on ice shelves, therefore making the behavior more common in the future.

Scientists have been concerned about the sudden decrease in Antarctic Sea ice since 2016 and the likely dire consequences for emperor penguins’ long-term survival.

“We estimate that we could lose the whole population by the end of the century,” Fretwell says. “It’s heartbreaking to think that the whole species may be gone if climate change continues on the path that it’s on at the moment.”

LaRue remains hopeful about the emperors’ ability to adapt, and she considers the recent high dive caught on film a testament to their hardiness.

“They’re incredibly resilient,” she says. “They have been around for millions of years; they’ve seen lots of different changes in their environment. It’s a question of how rapidly they’re able to deal with the changes that are happening—and how far they can be pushed.”

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