Inside One of Peru’s Most Vulnerable Penguin Colonies

Humboldt penguins are hardier than other species. Named for the plankton-filled Humboldt Current that flows up from Antarctica to South America, they’ve adapted over centuries to cycles of hardship and abundance driven by the presence or absence of El Niño. The climate phenomenon brings warm water from the west every two to seven years, driving away the cold-water fish that the penguins rely on.

“I don’t have high expectations about what I’m going to see,” Susana Cárdenas-Alayza, a biologist and the director of the conservation program at Punta San Juan, said as she prepared to check on the penguin colony a few weeks after the start of this year’s El Niño conditions.

Her low expectations were justified. Just a few years ago, the breeding colony at Punta San Juan was decimated by a one-two punch of avian flu in 2022 — which killed thousands of birds — and an El Niño in 2023 that dropped the population to only a few hundred. Now, just three years later, the birds are facing a so-called Super El Niño that is forecasted to be much stronger than the last.

At the start of this year’s breeding season, which typically spans March to December, there were about 200 nests at Punta San Juan. But when researchers checked on the birds after the fall peak, the penguins had already started to abandon their eggs.

Typically, penguin parents trade off staying at the nest to ensure their eggs or chicks are warm and guarded while the other parent is out hunting. But during El Niño years, food takes longer to find. Eventually, the hungry parent guarding the nest will abandon the post to find food as well.

“I’ve watched adults like leave their chicks and their chicks following them, like ‘cheep, cheep, cheep,’” Dr. Cárdenas said, mimicking the birds’ chirps.

Often the adults don’t return, choosing instead to resettle closer to more abundant waters. The abandonment of nearly an entire colony and the loss of a generation of penguins can happen in just a few weeks — as it has in Punta San Juan. Dr. Cárdenas is not expecting to see the colony’s numbers rise again until well after the El Niño has ended.

Punta San Juan isn’t the only site already experiencing steep declines this season.

Carlos Zavalaga, a seabird ecologist at the Universidad Científica del Sur in Lima, Peru, regularly visits Humboldt penguin colonies in Peru. He says he’s seen many nest abandonments like those at Punta San Juan this year. He expects emaciated and dead penguins to start appearing along the country’s shoreline as the El Niño intensifies.

“When you see the carcasses of penguins on beaches, that is an indication that the El Niño is really, really strong,” Dr. Zavalaga said.

Some research suggests that El Niños are becoming more intense as climate change warms the oceans’ waters. Extremely powerful Super El Niños like this year’s are still rare, but it can take years for ecosystems to recover from their effects.

In 1997-98, another Super El Niño destroyed 16 percent of the world’s coral reefs, caused natural disasters around the world and left Punta San Juan nearly devoid of animals for several years after.

“We were running around with spray paint to count all the dead animals in the beach,” said Patricia Majluf, a biologist who worked at Punta San Juan during that El Niño. “Every day there were new ones, so we had to recognize the old ones with paint.”

Dr. Majluf estimates that about 80 percent of the animal populations that she had spent her career working with were gone by the end of the 1997-98 El Niño: Humboldt penguins, cormorants, pelicans and fur seals, among them. The experience was so jarring that she shifted her career’s focus from local fieldwork to national and international marine conservation efforts after realizing that the problems in places like Punta San Juan were too big to solve locally.

Humboldt penguins will always experience some negative effects during El Niño years, but researchers say there are things humans can do to lessen other pressures on the birds’ food supply and habitats.

In the water, conservationists suggest expanding Peru’s marine protected regions — conservation areas where large-scale fishing and seafloor mining are banned — to include more of the waters where penguins typically hunt for fish. They also suggest strengthening restrictions and closing loopholes that have allowed industrial fishing to continue in some protected spaces.

On the shore, conservationists are focused on keeping the penguins’ breeding grounds as attractive to the species as possible, even during the years that El Niño has temporarily driven them away. This means ensuring that human activities like the harvesting of guano — seabird excrement widely used by humans as fertilizer and used by penguins to create nest-shielding burrows — are kept to a minimum.

“Even where you don’t see the animals now, you have to keep it in a good condition so that they find it as an appealing site to come back,” Dr. Cárdenas said.

But these protective measures are difficult to achieve. High turnover of political figures in Peru, where the 10th president in 10 years was recently elected, has made it challenging to sustain long-term conservation initiatives. Constant campaigning has drawn the political system closer to large fishing industries that make new conservation policies harder to pass, scientists say.

Dr. Majluf served as Peru’s vice minister of fisheries for just over two months in 2012 before resigning over disagreements about commercial fishing management. Without regulations to prevent fishing close to the shoreline and in sensitive ecosystems, as well as regulations that prevent fishermen from targeting juvenile fish that would otherwise help the population grow, she said the future for Punta San Juan was “not very bright.”

The penguin populations can recover. Humboldt penguins can dive deep — nearly 500 feet — for food, migrate long distances at a pace of 20 miles per hour to look for more favorable conditions and even breed a second time during the year if their first nest didn’t make it. But it takes time, making years like this one feel like limbo for conservationists.

“First we have to wait for the animals to come back,” Dr. Cárdenas said. “And then we’ll start making more conservation actions.”