Climate change - Antarctic Emperor Penguins and fur seals now endangered species

 

The beloved emperor penguin and Antarctic fur seal are now officially endangered. Here’s what can be done

The Conversation, CC BY-ND

Mary-Anne Lea, University of Tasmania; Jane Younger, University of Tasmania, and Noemie Friscourt, University of Tasmania

In 1902, British explorer Robert Falcon Scott spotted a large group of large black and white birds at Ross Island, Antarctica. This was among the many milestones of Scott’s famous Discovery expedition: the first breeding colony of emperor penguins.

Now, only 124 years since this penguin colony was discovered, emperor penguins have officially been listed as endangered, along with the Antarctic fur seal. As the world warms, Antarctic krill are shifting southwards and sea ice is shrinking at record levels. And these unprecedented changes are having a domino effect on these species.

These are the first penguin and pinniped – marine mammals that have front and rear flippers – to be given this conservation status in the Southern Ocean. Their perilous situation is a critical turning point, and shows how rapidly the Antarctic environment is changing.

At the same time, the spread of highly contagious avian influenza, or bird flu, adds a new and immediate threat to Southern Ocean wildlife, compounding the pressures of climate change on stressed species.

Antarctic fur seal with pups at Sailsbury Plain on South Georgia. The number of fur seals has dropped by over 50% since 1999. Posnov/Getty

Dramatic declines linked to climate change

The first emperor penguin breeding colony was discovered at Cape Crozier, on Ross Island, during Robert Falcon Scott’s Discovery expedition in 1902. A decade later, Scott’s Terra Nova expedition returned, in part to collect emperor penguin eggs. It was an ill-fated expedition, immortalised in Apsley Cherry-Garrard’s famous book, The Worst Journey in the World.

In the 1960s, Scott’s son, Sir Peter Scott, one of the founders of modern conservation, helped establish the International Union for the Conservation of Nature’s Red List. Just 124 years after those early discoveries at Cape Crozier, that same framework has now been used to classify emperor penguins as endangered. The swift arc from discovery to extinction risk is a striking reminder of how quickly the species’ fortunes have changed.

Over nine years, between 2009 and 2018, emperor penguin numbers fell by 10%. Their numbers are expected to halve by 2073.

Southern elephant seals are now officially listed as vulnerable. Mary-Anne Lea, CC BY-ND

The decline is more pronounced for Antarctic fur seals. Hunted to the brink of extinction in the early 1880s, by 1999 their numbers had rebounded to an estimated 2.1 million mature seals. But since then, the global population has decreased by more than 50%, to about 944,000 mature individuals.

In just a decade, they have been reclassified on the IUCN’s Red List, going from of “least concern” – those species that are widespread and at low risk of extinction – to “endangered”. The IUCN’s red list is the comprehensive information source on the extinction risk status of species. This shows the remarkable speed at which these seals are declining.

Climate change and bird flu

Both of these dramatic declines are linked to climate change. Warming ocean temperatures and a reduction in sea ice affect the availability of the Antarctic fur seal’s key prey, Antarctic krill. Krill are shifting southwards and moving deeper, potentially making them less accessible to some predators. Competition with a growing population of whales has also increased.

Emperor penguins, by contrast, are completely dependent on sea ice. They use it as a stable platform for courtship, incubating their eggs and rearing chicks. But as sea ice declines and becomes less reliable, their breeding success is increasingly threatened. If the ice breaks up before chicks are fully developed, many are unable to survive.

At the same time, the spread of highly contagious bird flu adds a new and immediate threat to Southern Ocean wildlife. High mortality associated with avian influenza has also caused the uplisting of the southern elephant seal to “vulnerable” this week.

Some elephant seal populations have experienced more than 90% of pups dying, alongside sharp declines in breeding adults. These represent tens of thousands of animals lost, with many Antarctic fur seals also dying as a result of bird flu outbreaks.

Emperor penguin chicks at Cape Crozier. Mary-Anne Lea, CC BY-ND

We need to know more

Emperor penguins, Antarctic fur seals and southern elephant seals are three of the more widely researched Southern Ocean predators. But there is still a lot we don’t know, because of the remote location and the difficulty of sustaining research over time. And there are many species we know far less about. Antarctic ice seals, including Weddell seals, crabeater seals, leopard seals, and Ross seals, have “unknown” population trends on the IUCN red list, meaning there is not enough data to know if numbers are declining.

These recent listings make clear the urgent and ongoing need for improved, real-time monitoring. We need to know much more about wildlife health and population trends, the Antarctic environment and sea ice quality.

Human-driven threats facing Antarctic wildlife are many, and cumulative. To respond, we need to better protect Antarctic habitat and the species that live there. We need to reduce the interaction of marine species with industrial fishing. And we must improve how we assess current and suspected threats in Antarctica, when there is growing evidence of impacts.

Defining these animals as endangered is a stark reminder of how quickly Antarctica is changing before our eyes. Without a rapid reduction in greenhouse gas emissions and sustained conservation action, these species may be lost forever.

Mary-Anne Lea, Professor in Marine/Polar Predator Ecology, University of Tasmania; Jane Younger, Senior Lecturer in Southern Ocean Vertebrate Ecology, Institute for Marine and Antarctic Studies, University of Tasmania, and Noemie Friscourt, Research Associate, Institute for Marine and Antarctic Studies, University of Tasmania

This article is republished from The Conversation under a Creative Commons license. Read the original article.