Penguins Showing Strain Under Climate Change

Feb. 14, 2009 -- Argentina's Magellanic penguins are moving north, laying their eggs later than they used to, and struggling -- often unsuccessfully -- to feed their chicks, all as a result of climate change.

These findings suggest the need for a major shift in the way we think about protecting penguins, as well as other marine creatures, said conservation biologist Dee Boersma, of the University of Washington in Seattle. She presented the results of more than 25 years of research today in Chicago at the annual meeting of the American Association for the Advancement of Science.

"Penguins are incredible sentinels for our environment, particularly the ocean environment," Boersma said. "They're already telling us there are severe changes going on."

Fourteen of the world's 19 penguin species are threatened or endangered, with a few species in deep trouble. A major reason for their decline, Boersma said, is an increasingly variable climate, with more frequent El Nino and La Nina events that can drastically change water temperatures and nutrient levels from year to year. Climate models predict more of this type of variability to come.

Related Content:

• Emperor Penguins Marching Toward Extinction
• HowStuffWorks.com: Penguins
• Animal Planet: Valentine's Day Hub
• More Discovery News

Since the early 1980s, Boersma has been studying and tagging Magellanic penguins at a site called Punta Tombo on the Argentine coast. She has been using satellites to track the animals since 1997. Punta Tombo is home to the world's largest population of Magellanic penguins, which live along the southern tip of South America in Argentina, Chile, and the Falkland Islands.

There are still more than a million breeding pairs of these birds alive today, but Boersma has seen Punta Tombo's numbers drop from its peak of more than 350,000 pairs in the 1970s to about 200,000 in 2006. Magellanic penguins are now classified as "near threatened" because populations are in such rapid decline.

Punta Tombo's penguins have been doing their best to adapt to the environmental turmoil, Boersma said, but it's been hard work. Their prey, which includes squid, anchovies and other small fish, have moved north. So, the birds are now swimming an average of 60 km (37 miles) further to get food for their young, Boersma reported last year in the journal BioScience. Chicks are often left hungry for up to two weeks. Many don't make it.

It's as if the penguins had bought homes in suburban Chicago, only to have their jobs moved from the city to Des Moines, Boersma explained. A longer commute requires extra energy that they need to recoup with extra food. "The cost of living has gone up," she said.