Penguins are some of the slowest-evolving birds in the world

How are penguins affected by climate change?

The Antarctic is rapidly changing as the world warms, with the West Antarctic Ice Sheet estimated to be among one of the most rapidly warming areas of the world. Between 1957 and 2006 the area is thought to have warmed by almost 0.2⁰C a decade, around twice the rate of the rest of the continent.

Rising temperatures have caused the ice sheet to melt at an increasing rate. The Thwaites glacier, which is already responsible for around 4% of global sea level rise, is estimated to begin collapsing before 2030.  

If the entire glacier breaks up, the sea level could rise by over 65 centimetres globally, and threaten low-lying islands such as the Maldives, the Seychelles and parts of Hawaii. 

The loss of ice also has implications for penguins too, which use sea ice to breed, rest and moult. Their prey, such as Antarctic silverfish, also depend on ice to reproduce and shelter and any declines in prey will affect penguin populations further.

The study looked at how the different traits of the species have affected their populations in past climate change events to help understand how they will adapt to the Anthropocene.

The researchers found that penguins which migrate and forage offshore, such as the Adélie penguin, responded better to climate shifts during the last Ice Age than those which inhabit specific residential areas, such as the African penguin.

Modern climate change, however, will likely be too fast for penguins to adapt in time.

‘Penguins are perfectly capable of adapting to shifting climate on a time scale of tens of thousands or even millions of years, but we are now facing unprecedented rates of global heating,’ Daniel says. ‘If the polar ice sheets melt away rapidly in the next century, for example, there just won’t be enough time for penguins to evolve to the new conditions.’

Even the migratory, and larger, penguins which have previously responded better to changing climates in the past will struggle to keep up with modern climate change. At the current rate of warming, even the biggest species of penguin, the emperor, will see around 70% of their colonies wiped out by 2050. 

Though they may have lasted for tens of millions of years, and faced climate change many times before, the ability of penguins to survive the Anthropocene is uncertain. Cutting global carbon emissions and limiting the effects of warming in the southern hemisphere will be crucial to preserving these iconic birds.