As Oceans Warm, King Penguins’ Food Moves Farther Away. That’s a Problem
The already treacherous journey for nourishment will get increasingly challenging for penguins in the years ahead
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King penguins, the iconic tuxedo-clad critters with bright yellow accents, can breed on just a handful of ice-free islands near Antarctica. Adult penguins take turns to forage for food, traveling hundreds of miles to reach the Antarctic polar front—a nutrient-rich stretch of ocean where cold deep water meets warmer patches. The area hosts an array of tasty marine life that the penguins gobble down and bring back for their chicks, who hungrily await their return to the nest.
But new research suggests that their populations could suffer up to a 70 percent decline by 2100 if they don’t find a new home. As Merrit Kennedy reports for NPR, climate modeling suggests that their food-rich current is moving further away, which will make it hard for them to complete the already treacherous journey.
For the study, published this week in Nature Climate Change, Emiliano Trucchi, a researcher in evolutionary genetics from the University of Ferrara in Italy, and Céline Le Bohec of the Université de Strasbourg developed a model to map out the most favorable islands for penguins in a warming world. As Karen Weintraub reports for The New York Times, they also looked at historical and genetic records of penguin distribution to compare how the tuxedo-clad critters reacted to past changes in climate.
The results suggest a bleak outlook. Even in a low-emissions test, climate change could threaten up to half of the king penguin populations. As Trucchi tells Kennedy: "This is really surprising to us, to find such a massive change is going to happen in such a short time frame.”
The model suggests that climate change will shift the Antarctic polar front closer to the South Pole, moving the penguins’ main source of food further away and forcing the creatures to swim increasing distances to forage, reports Katherine Hignett of Newsweek.
Penguins have historically traveled long distances to eat, Hignett writes, and even survived dramatic climate shifts. But the new study suggests these distances will increase past the point they are capable of venturing. The model assumes penguins can travel up to 430 miles from where they breed to find food—but even at their current shorter ventures, Trucchi tells Kennedy, the creatures are already suffering. As that distance increases, more of their chicks will starve while waiting for their parent's return. The penguins will be forced to relocate.
Our reliance on fossil fuels and other greenhouse gas-emitting activities are largely driving this rapid change in climate that will chase the creatures away. But other human activities, such as industrial fishing, further dwindles the penguins’ food supplies. Researchers aren’t sure how penguins will adapt to this change, but they say their findings should be considered low estimates of the possible impacts.
As for finding a new home for the penguins? It will be no small feat. While Weintraub reports that some islands nearby could become more habitable with climate change, it likely won’t help king penguins.
A sudden influx of king penguins could harm other species. And the creatures are particular about their dwelling spaces. In addition to a reliable source of food like the Antarctic polar front, king penguins also need tolerable temperatures, islands with smooth beaches (not rocky ones) and relatively little ice, Hignett writes.
"We are talking about 1 million individuals that need to find a new place to live," Trucchi tells Kennedy.
Ceridwen Fraser, a marine molecular ecologist at the Australian National University who was not involved in the research, tells Weintraub that the study is another example of the impact of climate change on species around the world. Its impacts are wide reaching—from aiding the spread of invasive species to increasing energy demands of polar bear life. And if we can't reduce our emissions, many critters that can't adapt to their changing habitat will soon be in trouble.