The World’s King Penguins Are Disappearing at a Startling Rate and Scientists Don’t Know Why

The world’s largest king penguin colony has shrunk nearly 90% since the 1980s, researchers say, and scientists don’t quite know why.

The findings, outlined in an article in the journal Antarctic Science, were achieved by comparing serial and satellite images in 2015 and 2017, with those from the 1980s, respectively. Breeding pair numbers fell 88% between the 1980s and today.

Some 60,000 penguin pairs can be spotted in the recent images, down from half a million pairs recorded in the 1980s.

The colony in question lies on France’s Île aux Cochons, or Pig Island, in the subantarctic Crozet Archipelago. The uninhabited island also hosts the largest colony of wandering albatrosses in the Indian Ocean, as well as large populations of various species of seal—southern elephant, Antarctic fur and subantarctic fur seals. There are also substantial numbers of northern rockhopper penguins, an endangered species.

Second only to the emperor penguin in size, the king penguin breeds on the more temperate islands north of the Antarctic coast.

Whilst it is not clear what generated this particular population decline, globally speaking the king penguin—like other bird populations—could be at risk from climate change. The worry is that as the climate warms further, the birds will be forced to relocate, taking them further from their foraging grounds. Fetching food for their chicks would thus become an impossible task.

King penguins largely breed on the sub-Antarctic islands between 45 and 55 degrees South.

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