98% of emperor penguin colonies could be extinct by 2100 as ice melts – can Endangered Species Act protection save them?

19th August, 2021.      //   General Interest  // 
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Antarctica’s sea ice is melting, putting penguins in jeopardy. Raimund Linke/The Image Bank via Getty Images

 

Emperor penguins live in cold circumstances that humans would deem harsh on Antarctica’s coasts. They do, however, have a small comfort zone, similar to Goldilocks: if there is too much sea ice, excursions to get food from the ocean become long and laborious, and their young may starve. The chicks are at risk of drowning due to a lack of sea ice.

Climate change has thrown that delicate equilibrium into disarray, putting the entire species at danger.

My colleagues and I show in a new study that if current global warming trends and government policies continue, Antarctica’s sea ice will melt at a rate that will drastically reduce emperor penguin numbers, to the point where almost all colonies will be extinct by 2100, with little chance of recovery.

That’s why the US Fish and Wildlife Service suggested adding the emperor penguin to the Endangered Species Act’s “threatened” list. On August 4, 2021, the plan will be published in the Federal Register, kicking off a 60-day public comment process.

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When the sea ice becomes too thin, it might break up early, resulting in the drowning of penguin babies. Sylvain Cordier/DigitalVision via Getty Images

Climate change is the greatest threat to emperor penguins. Unless countries implement strategies to limit the greenhouse gases that cause global warming, the sea ice cover they rely on will be disrupted.

The Endangered Species Act of the United States has already been used to preserve other species that are largely endangered by climate change, such as the polar bear, ringed seal, and many coral species, all of which are classified as threatened.

Because Emperor penguins do not dwell on U.S. soil, parts of the Endangered Species Act’s habitat protection and anti-hunting provisions do not apply to them. However, being classified under the Endangered Species Act may have certain advantages. It might be a method to mitigate the potential for harm from US fishing boats operating in the area. With the Biden administration’s planned measures, the listing may eventually put pressure on US agencies to take steps to reduce greenhouse gas emissions.

 

Marching toward extinction 

During my Ph.D. research, I first observed an emperor penguin in Pointe Géologie, Antarctica. My colleagues and I proceeded to see the emperor penguin colony located only a few hundred meters from the French research station – the same colony depicted in the movie “March of the Penguins” – as soon as I arrived on the island, before our team unloaded our luggage.

We sat far away, using binoculars to view them, but after 15 minutes, a few penguins approached us.

With their limping stride, people believe they’re ungainly, almost funny, yet emperors stroll on the sea ice with a tranquil and serene elegance. I can still feel them tugging at my shoelaces, their curious eyes darting about the room. I hope that my children and future generations will have the opportunity to meet these ice lords.

Since the 1960s, scientists have been studying emperor penguins near Pointe Géologie in Terre Adélie. Scientists are now using those decades of data to assess the consequences of anthropogenic climate change on penguins, their sea ice habitat, and their food supplies.

Fast ice, which is sea ice connected to land, is where the penguins breed. They do, however, seek for food on the pack ice, which is made up of sea ice floes that move with the wind or ocean currents and may combine. Sea ice is also necessary for resting, moulting, and escaping predators.

When sea ice disappeared and more male emperor penguins perished in the late 1970s, the penguin population at Pointe Géologie fell by half, and the colony never fully recovered from huge breeding failures, which have been occurring more often.

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In a world with high greenhouse gas emissions, the number of nesting pairs of emperor penguins at Pointe Géologie is expected to plummet. The graph is based on the RCP 8.5 high-emissions future climate scenario. Jenouvrier et al., 2020, CC BY-ND 

The US Fish and Wildlife Service encouraged an international team of scientists, policy experts, climate scientists, and ecologists to provide research and projections of the threats posed by climate change to emperor penguins and their future survival in order to determine whether the species could qualify for protection under the Endangered Species Act.

Every colony will be in decline by 2100

Emperor penguins have evolved to live in their present habitat, but they have not developed to withstand the fast consequences of climate change, which threaten to alter their world.

Decades of study by an international team of scientists have helped to show the necessity for protection.

In 2009, I participated in groundbreaking study that predicted the colony of Pointe Géologie will be extinct by the end of the century. And it won’t be limited to that colony. In 2012, my colleagues and I examined all known emperor penguin colonies found in satellite photos and concluded that if greenhouse gas levels continue to rise, every colony will be in decline by the end of the century. Penguin activities that might help them adjust to changing environmental conditions were shown to be ineffective in reversing the expected worldwide decrease.

Major environmental alterations are already increasing the risk, such as the late development and early disappearance of sea ice on which colonies are based.

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The recent collapse of Halley Bay, Antarctica’s second-largest emperor penguin colony, is a striking example. In 2016, sea ice broke up early, killing almost 10,000 chicks. The colony has yet to fully recover.

By factoring in such severe occurrences, we calculated that 98 percent of colonies will be extinct by 2100 if current greenhouse gas emissions continue, and the world population will drop by 99 percent compared to historical levels.

 

Meeting the Paris goal  could save the penguins 

According to the findings of the new study, if the world fulfills the Paris climate accord objectives of keeping warming below 1.5 degrees Celsius (2.7 degrees F) relative to pre-industrial temperatures, enough habitat might be protected to stop the emperor penguins’ decline.

However, the globe is falling short of the Paris Agreement’s goals. According to Climate Action Tracker, countries’ present policy paths have a higher than 97 percent chance of surpassing 2 degrees Celsius (3.6 F). With recent government statements taken into account, the rise is expected to be about 2.4 degrees Celsius (4.3 F).

As a result, the emperor penguin looks to be the classic “canary in the coal mine.” The fate of emperor penguins, as well as much of life on Earth, including mankind, rests on today’s decisions.

 

This article was written by: Stephanie Jenouvrier, an Associate Scientist from the Woods Hole Oceanographic Institution.