Emperor penguins (Aptenodytes forsteri) might be adapting to a warming planet, according to a new study. It turns out that these penguins are more willing to locate themselves in the face of changing temperatures.
Researchers from British Antarctic Survey looked at satellite data on the movements of four Antarctic emperor penguin colonies and found that these birds are shifting from their traditional breeding grounds to thicker ice-shelves. An ice shelf is a large, floating block of ice that forms where a glacier meets a coastline. Generally, penguins breed on thin sea-ice, sometimes up to 18 kilometers or 11 miles offshore. The thin floating sea ice gives them easy access to water where they hunt for fish.
Now, rising temperature and low sea ice has forced emperor penguins to move to thicker ice shelves, especially now when thin sea ice forms later than usual. For the study, researchers analyzed data from ENVISAT synthetic aperture radar data and Quickbird satellite data to study the behavior of four penguin colonies living in warmer areas where the availability of sea ice is low. As the climate changes, species need to adapt to a shifting environment. Now, scientists have found out that emperor penguins, at least, may be more adaptable than previously thought.
‘Previously we thought emperor penguins didn’t breed on these ice shelves as they are too clumsy and couldn’t climb up the cliffs that form at their edges. But through satellite images we’ve now found evidence of several colonies that do breed on top of these ice shelves,’ explains Dr Peter Fretwell of NERC’s British Antarctic Survey (BAS), lead author on the paper. ‘We don’t know how the emperor penguins go up and down off the ice shelf. In one case they’re going up and down a 30 meter ice shelf but we don’t know if they’re jumping off it, sliding down or climbing because we haven’t been able to visit them,’ Fretwell says.
“Satellite observations captured of one colony in 2008, 2009 and 2010 show that the concentration of annual sea ice was dense enough to sustain a colony,” Peter Fretwell said in a news release.
“But this was not the case in 2011 and 2012 when the sea ice did not form until a month after the breeding season began. During those years the birds moved up onto the neighbouring floating ice shelf to raise their young ones.”
This isn’t the first study that has explored the changes in penguin behavior. A related research by British Antarctic Survey scientists and colleagues had shown that these birds were abandoning their traditional breeding grounds for stable ice shelves. In fact, penguins are now climbing steep ice shelf walls, some 30 meters or nearly 100 feet high, to find a good breeding spot.
We know only a little about Emperor Penguins because they lay their eggs during winter. It is very difficult for people to see Emperor Penguins at this time except with a very strong flashlight. Emperors live so far south that the sun never rises for 3 months. Here, through the window of a helicopter, you see clumps of Emperor penguins that are nesting on the frozen sea. The icebergs are resting on the ocean bottom and lock the sea ice in place long enough (7 months) for the chicks to grow up.