A recent study’s findings suggest that the Emperor Penguin population in Antarctica could fall by more than a third by 2100
ANTARCTICA – Vast frozen wasteland, apparently barren of life; if not for the vast colonies of Emperor Penguins dappling the white ice with black specks, but for how much longer?
A new report, released on Sunday, July 29 by the Woods Hole Oceanographic Institute suggests that Antarctica’s Emperor Penguin population could fall by a third by the end of the century. “The population is declining. Unless something changes to stop that, the population will go into extinction,” said Hal Caswell, senior scientist and one of the report’s authors. Emperor Penguin numbers have already suffered greatly due to intense global warming in the late 1970s.
The report is based on a 50-year intensive study of the Emperor Penguin colony in Adélie Land, in Eastern Antarctica, supported by the French Polar Institute and Zone Atelier Antarctique. The scientists collected biological measurements of the penguins; charting population growth and decline, observing their mating, foraging and chick-rearing patterns, and following marked individuals.
This normally hardy penguin is at risk due to depleting levels of sea ice, caused by global warming. According to recent studies, Antarctica has a lost a quarter of its sea ice over the past 100 years as temperatures have risen at the Antarctic Peninsula by around 2 and a half degrees. “If sea ice declines at the rates projected by the IPCC (Intergovernmental Panel on Climate Change) climate models, and continues to influence Emperor Penguins as it did in the second half of the twentieth century in Adélie Land at least two-thirds of the colonies are projected to have declined by greater than 50 percent from their current size by 2100,” said Stephanie Jenouvrier, lead author and a scientist at Woods Hole. “None of the colonies, even the southern-most locations in the Ross Sea, will provide a viable refuge by the end of the twenty first century.”
The problem is not with the penguins directly, but the decline in sea ice is causing a reduction in the supply of krill, their main food source. Krill are tiny crustaceans that are eaten by whales, seals and of course penguins. Young krill feed on algae living in the sea ice, so a loss of ice means a decrease algae, and thus the krill population.
A loss of sea ice in the first instance may appear to be beneficial to the penguins. “The role of sea ice is complicated,” said Jenouvrier. “Too much ice requires longer trips for penguin parents to travel to the ocean to hunt and bring back food for their chicks. But too little ice reduces the habitat for krill, a critical food source for Emperor Penguins.” However, Jenouvrier goes on to say that the report takes into “account both the effects of too much and too little sea ice in the colony area.”
Researchers say urgent measures are needed to help the penguins survive potential extinction. Legal protection is required under the US Endangered Species Act, which is based on the global population dynamic and by creating marine reserves off Antarctica. Andrea Kavanagh, director of global penguin conservation for the Pew Charitable Trusts stated that this would put large areas of ocean off limits to fishing, reducing the pressure on krill stocks, therefore giving the Emperor Penguin a better chance of survival.
– Hannah Seaton, Correspondent (Antarctica)
Image Courtesy: Christopher Michel (https://www.flickr.com/photos/cmichel67/11240219084), Licensed under the Creative Commons Attribution 2.0 Generic | Flickr