Emperor penguins adapt to global warming
Rising temperatures in the Antarctic have led to the largest and heaviest species of penguin - the Emperor penguin - being classified as 'near threatened'.
However, recent satellite images obtained by an international collaboration of conservation groups - led by Peter Fretwell at the British Antarctic Survey - suggest that the Emperor penguin may be much more adaptable to a changing climate than was previously thought.
Emperor penguins rely on the formation of ice floes around the Antarctic coastline in order to breed. These ice sheets provide easy access to the sea, so that the giant birds are able to find fish to eat while raising their young on dry land.
However, rising temperatures mean that the extent of the ice floes which form each winter is shrinking, giving the penguins less room to breed. Unusually warm spells during the winters of 2011 and 2012 threatened to put the penguins under exceptional pressure, as the ice floes hardly formed at all.
But this also gave researchers their first opportunity to see how the penguins would behave when their usual breeding grounds were not available - with many suspecting that the penguins would simply not breed at all in those years.
Satellite images taken during those years, however, have been found to show emperor penguin breeding colonies perched on top of some of the continent's fresh-water ice shelves, often surrounded by thirty-metre-high cliff faces.
Emperor penguins are agile swimmers, but are usually thought of as quite clumsy animals on dry land, and so their ability to scale such ascents came as quite a surprise. But detailed examination of the satellites imaged showed that the penguins had worked out a long and winding path they could tread to reach the top of the shelf.
This adaptability gives hope that the emperor penguins may not be quite so vulnerable to population collapse as previously thought, should their prefered breeding grounds disappear in coming years.
The work is written up in online journal PLOS ONE.