Extreme weather along the Argentine coast is killing chicks of Magellanic penguins that roost there. A 28-year study of the birds has found very hot years and very wet ones claiming as many as 50 percent of new chicks in the worst of times.
“Penguin [chicks] don’t do well when they get wet,” said Dee Boersma, a researcher at University of Washington who’s been tracking the birds at the Punta Tombo peninsula, the largest colony of Magellanic penguins, since 1983.
New chicks that encounter a rainstorm before they grow out a waterproof coat get drenched and die of hypothermia, she reports in a study published Wednesday in the journal PLOS ONE. "If you've ever had a down sleeping bag, and got it wet, all the insulating properties are lost," Boersma explained.
Not every one of the extreme weather events was deadly — only 16 of the 233 storms the team observed killed chicks. But climate researchers predict storms hitting the Argentine coast are just going to get worse.
"We're going to see years where almost no chicks survive if climate change makes storms bigger and more frequent during vulnerable times of the breeding season as climatologists predict," Ginger Rebstock, Boersma’s co-author on the study, said in a release.
"This year we’re not going to have any chicks that will die from rain," Boersma said. "But we’ve had a lot of chicks that die this year from heat, because it’s been hot."
Weather isn’t the only thing threatening the Magellanic penguins; they’re starving as well. In a 2008 study, Boersma showed that decreasing sea ice meant the birds needed to swim up to 40 miles farther to reach their food, she told the New York Times then.
About 1,000 miles south of the Magellanic penguins’ breeding spot, Antarctic penguins are also feeling the effects of climate change, something researchers first started observing in the early 2000s.
Among those species, "there are winners and losers," Peter Fretwell, a researcher at the British Antarctic Survey, told NBC News.
For example, the emperor penguins are changing their behavior with the times, Fretwell has found, abandoning their traditional shoreline sea ice breeding spots — which are melting quickly in the last decades — in favor of high ice shelves. If current predictions hold, “we expect to lose about half of all emperor penguins in the next 50 years,” he said.
Among the worst hit are chinstrap penguins, which live in an isolated region of Antarctic and feed exclusively on krill, a kind of crustacean. Abundance of krill near the chinstrap colonies has dropped almost 80 percent in the last 30 years, as sea ice has declined, a group of researchers reported in 2011.
Adelie penguins that live in that region of Antarctica are similarly struggling to find food. But populations in a different part of the continent, near the Indian Ocean, are growing. That's because miles of sea ice that existed decades ago have in recent years have given way to open sea. “Instead of having to walk 10 kilometers ( 6 miles) to get to the water, they walk down to the beach and swim,” Wayne Travilpiece, who studies Adelie penguins at the NOAA Southwest Fisheries Science Center, told NBC News.
As for the Magellanics, there’s a chance humans can help, in ways that don't involve reprogramming the weather. Boersma said protecting Punta Tombo peninsula as a marine preserve would mean the penguins wouldn't have to compete with humans that fish there for food.
Nidhi Subbaraman writes about science and technology. You can follow her on Facebook, Twitter, Google+.