Magellanic Penguins Of Argentina Threatened By Climate Change

Scientists Predict We Will Soon See 'Years Where Almost No Chicks Survive'

By Ajit Jha on January 29, 2014 

Magellanic penguin chicks, like the one shown here, are born without the protective feathers needed to survive the harsh weather climate change has created. (Photo: Shutterstock)

Climate change is decimating the population of penguin chicks from the world's largest colony of Magellanic penguins, not just indirectly by making their food resources scarcer, but directly from rainstorms and heat, according to a new University of Washington study. The findings published in the January 29 issue of PLOS ONE take into account 27 years of data collected in Punto Tombo, Argentina, which is the world's largest breeing ground for Magellanics. Punto Tumbo is home to 200,000 pairs during breeding season, which lasts from September to February. "It's the first long-term study to show climate change having a major impact on chick survival and reproductive success," said lead author Dr. Dee Boersma, a UW biology professor, in a press release.

There are 17 species of penguins in the world, 10 of which (including Magellanics) breed in relatively dry and temperate area devoid of snow. Punta Tombo, for example receives an average of 0 to 4 inches of rainfall a year. The penguins have developed a lifestyle dependent on the arid climate, and rainfall can actually kill chicks. When temperature plummets in November and December, baby penguins between the ages of 9 to 23 days can sometimes fail to warm up and dry off after rain, leading to their death. After 25 days, chicks have enough plumage for protection.

While adult penguins can sustain through harsh downpour and scorching heat, penguin chicks lacking waterproof feathers can't. Not even their parents can save them. The young ones cannot take a dip in waters to protect against spiking heat as adults can. An average of 65 percent of chicks died per year, said Boersma. How they die, though, is what matters. Starving killed an average of 40 percent every year, while climate change contributed to 7 percent deaths. That number is a bit misleading, however, in certain years it alone caused 43 percent killings, said Boersma. In addition, it is hard to tease apart the causes of chick deaths. "Starving chicks are more likely to die in a storm," Boersma pointed out.   

The increased precipitation and the number of storms every breeding season is impacting the population of penguins, according to said Ginger Rebstock, a UW research scientist and the co-author of the paper. There were more storms between 1983 and 2010 in the first two weeks of December when newly hatched chicks are less than a month old. And it could 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," Rebstock said.

Yet another important observation made over the 27 years by the researchers is that penguin parents are increasingly delaying arrival to the breeding site. Boersma hypothesizes that this might have something to do with food supply: that the fish the penguins eat are also arriving later than usual. The implication here is that the chicks - born later because of the late arrival by their parents - won't have grown their protective cover by November and December when storms pick up.

Given the situation, Boersma recommends creating a protected marine reserve to ensure that the largest colonies of Magellanic penguins have enough to eat while raising their chicks. This could stem the tide change currently occurring in penguin populations. The study was supported by the Wildlife Conservation Society, the UW, the Office of Turismo in Argentina's Chubut Province, the Global Penguin Society, and the La Regina family.

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