A new study has revealed a surprising silver lining to the unending bad news about antarctic warming, for one species at least, as it was discovered that adélie penguins actually do rather well in the iceless summers. By swimming instead of walking to find food, they expend less energy searching for sustenance, resulting in bigger adults and thriving chicks. The findings were published in Science Advances.
It’s no great secret that Antarctica has taken a beating from climate change in recent years. Unprecedented high temperatures only lasted nine days in February before the record was smashed by an even higher recording of over 20°C (68°F). The result is an iceless landscape that spells bad news for some endemic species like the emperor penguins as well as coastal communities at risk from rising sea levels.
There seems to be one animal, however, that isn’t exactly hating the new landscape, as it was discovered that adélie penguins in continental East Antarctica seemingly thrive without ice. Their behavior was recorded in an unusually ice-free breeding season from 2016 to 2017, the effect of which was compared to other, more traditionally chilly breeding seasons to see how the growth of chicks and adults changed.
Adélies usually waddle across the ice to access the water before hunting for krill. During the swim, they are reliant on cracks in the sea ice to breathe, which aren’t always associated with a conveniently placed air hole. With the ice gone, the penguins could switch straight to their more effortless swimming mode, free to breathe whenever they please without pesky ice sheets separating the best krill spots from precious oxygen. With greater and easier access to food, their chicks grew faster and the adults grew fatter, painting a picture of success in a drastically transformed landscape.
The researchers note that their findings appear to contradict existing research on adélies – which are considered a sentinel species for climate change in Antarctica – that mostly imply they wouldn’t fare well in a hotter climate. However, they highlight that such studies looked at correlations whereas their study, comparing the results of four breeding seasons including one completely without ice, draws conclusions from experimental comparisons.
Understanding how key species will cope with increasing temperatures is a crucial area of research as climate models predict that the Antarctic will rapidly lose sea ice as the 21st century progresses. While more research needs to be carried out to better understand how changing sea ice and temperatures will affect adélies as a species, it’s possible it's not all bad news for nature’s naughtiest penguin.