(Image: A. M. Thierry – Ancel/CNRS – IPEV)

If you spent most of the day huddled on the ice sheets of Antarctica, you’d turn blue too.

Emperor penguins live and breed in a harsher climate than any other species of bird. Temperatures at the bottom of the world can fall as low as -40 °C, and winds up to 40 metres per second whip across the landscape. With no windbreaks to protect them, the penguins are forced to pack together tightly.

To study how the animals cope, Dominic McCafferty at the University of Glasgow, UK, and colleagues used a thermal imaging camera to photograph groups of emperor penguins on islands off the coast of East Antarctica. The camera revealed how much heat the birds were losing to the surrounding air.


Surprisingly, the images revealed that the surfaces of the penguins’ bodies – shown as dark blue in the photo above – were colder than the sub-zero air around them. That suggests they were losing almost no heat at all.

But the freezing conditions could be the least of the penguins’ worries as rising temperatures threaten to destroy their habitats.

Journal reference: Biology Letters, doi.org/mgj