You’ll find them in freezing temperatures but a new study found that Antarctica’s emperor penguins may have struggled with the cold during the last Ice Age when temperatures were cooler.
Researchers looking at how climatic changes have affected the highly cold-adapted penguin – the tallest and heaviest of all penguin species – over the last 30,000 years suggest there were only three populations in the last Ice Age, Discovery News reported.
But as temperatures have risen since then, the species has bounced back and there are now seven times more emperor penguins in many more locations, said joint lead researcher Jane Younger.
“We hadn’t really thought about the fact that it would be too cold for them in the past,” Younger, a PhD student at the University of Tasmania, told AFP.
“They live through life in minus 30 degrees Celsius (-22 Fahrenheit) now so they are pretty cold adapted.”
By examining the genetic diversity of modern and ancient penguin populations, scientists from the universities of Tasmania, Southampton and Oxford in Britain, as well as the Australian Antarctic Division were able to estimate these numbers over time. They found that penguin population numbers began rising over the last 12,000 years when temperatures rose by an average of about 15 degrees Celsius and the amount of sea ice around Antarctica began to reduce.
Younger said the warmer temperatures likely allowed penguin chicks a better chance at survival during cold winter months – when temperatures would have dropped to minus 45 degrees Celsius during the ice age.
Too much sea ice could have also reduced the locations available for breeding, while a shrinking of ice would have allowed for more open ocean to feed, she said.
We were actually really surprised by this. What we had thought was that the ice age, because there was so much more sea ice, which they need (to breed), and because they are so cold-adapted, that this would probably be a good thing for them,” she said.
Emperor Penguin Population Has Become 7 Times Larger Since Last Ice Age