Swamp Stomp
Volume 18, Issue 11
The king penguins of the Antarctic sea may be the next charismatic species faced with the daunting challenge of moving to escape the impacts of climate change. A study recently published in the journal Nature Climate Change suggests that, unless warming greenhouse gases in the atmosphere are reduced, up to 70% of the king penguin population will have to move or face starvation by the end of the century.
Due to warming ocean temperatures, the Antarctic polar front, a nutrient-rich band of water in the Southern Ocean from whence king penguins derive 80% of their diet, is migrating closer to Antarctica and farther away from the southern archipelagos where the penguins roost. While the penguins can swim up to 400 miles round trip from the southern islands to the polar front, if the band moves much farther south, it will be out of reach for most of the penguin colonies.
Additionally, the lack of sea ice, which allows penguins to rest while hunting in the open ocean, may further threaten the species capacity to feed itself as warming continues. “They will need to either move somewhere else or they will just disappear,” said Dr. Emiliano Trucchi, an evolutionary biologist at Italy’s University of Ferrara and one of the study’s senior authors. “The largest colonies are on islands that will be too far from the source of food.”
The largest colonies of king penguins, home to a full half of the species population, are located on Prince Edwards and the Crozet Islands, south of Madagascar in the Indian Ocean. According to the researchers’ “business as usual” climate change model, the populations on these islands would likely lose their habitat entirely by the end of the century. Another 21% that live on the Kerguelen Islands in the Indian Ocean and the Falkland Islands off the South American coast will likely find themselves far enough away from their food source that they may be incentivized to relocate to islands farther south.
Yet, relocation may not be as simple as moving farther south to islands closer to the new Antarctic polar front. Unlike the larger emperor penguins, king penguins require ice-free islands with sandy beaches, leaving the species with few additional islands closer to Antarctica to move to as many are rocky, covered in ice, or have other species of penguins already living there. “We are talking about one million individuals that need to find a new place to live,” says Trucchi, noting that “the endpoint of this massive relocation is hard to predict.”
Despite the grim finding, the researchers suggested that some islands, such as Bouvet Island in the Southern Ocean, may be able to be colonized by king penguins as temperatures warm if humans take steps to protect them. “If there are some islands that are likely to be relatively safe, like those in the south, then we know about that now, and we can potentially protect those from other threats like fishing and tourism – to give animals the best chance of survival,” says Dr. Jane Younger, evolutionary ecologist at Loyola University Chicago.
The researchers ultimately argue that mitigating climate change is the best chance we have at saving king penguin habitat; using a model in which greenhouse gases were reduced enough to prevent global temperature from rising more than 2-degrees Celsius, they found that the majority of the population would not need to migrate.
“These are kind of poster children for what’s going to happen with climate change,” said Dr. Ceriden Fraser, a marine molecular ecologist at the Australian National University in Canberra. “People wouldn’t care as much if it were a slug or a slime mold, but the same sorts of impacts will happen to many different species. In a way, it’s good for us to see these impacts happening to animals we love, because it might spur a little bit of action.”
Sources:
- Harvey, Chelsea. “Antarctica’s Iconic King Penguins May Have to Move South: But suitable islands for breeding may be harder to find.” Scientific American. E&E News, 27 February 2018. Web. 4 March 2018.
- Kennedy, Merrit. “Scientists Predict King Penguins Face Major Threats Due to Climate Change.” North Carolina Public Radio. National Public Radio, Inc., 26 February 2018. Web. 5 March 2018.
- Winetraub, Karen. “King Penguins Are Endangered by Warmer Seas.” The New York Times. The New York Times, 26 February 2018. Web. 5 March 2018.