The largest colony of king penguins in the world shrinks

This was the largest colony of king penguins in the world: about 500,000 breeding pairs lived on the island of Pigs, one of the Crozet Islands, south of Africa. from South. But on the subantarctic island, something striking is going on, an international team of biologists writing this week in Antarctic science. In 35 years, the number of king penguin pairs has decreased to about 60,000, a decrease of nearly 90%. They conclude on the basis of aerial photographs and satellite images.

The discovery is remarkable because in recent decades, king penguins are improving day by day. This second largest species of penguin in the world (only emperor penguin is larger) is ranked 'no threat' on the IUCN red list and even increases in other places (such as South Georgia). ). In the world, the species has about 1.6 million breeding pairs (although the estimate dates from 2013, so even before the current research.)

The fact that the population of l 39; Pig Island is almost decimated can have several causes. The dipole of the Indian Ocean (a variation in sea-water temperature, comparable to El Niño) may have led penguins to catch fewer fish in 1997, which resulted in a decline significant population. This has also occurred with a smaller colony near the island of Possession. Earlier this year, other Nature Climate Change biologists have already warned that king penguins on the Crozet Islands may be struggling with climate change. They should then swim too far in areas where they can find enough fish because the water around the islands gets too hot.

Another reason might be that the colony has separated and some of the penguins have migrated. The question is then only: where? The Crozet Islands being very isolated, a long-distance migration is unlikely. Some new neighboring colonies have been observed in aerial photographs, but these figures can not fully explain the narrowing.

Another explanation is the presence of wildcats: they could have provided young penguins. Or maybe a contagious disease has erupted, suggest biologists. But to be certain, there is only one thing to do: visit the colony. They want to do it in 2019.