- University of Delaware / Megan Cimino
Penguins are some of the most beloved wild animals in the world, and Adélie penguins are some some of the cutest. But these miniature creatures – a little over two feet tall and weighing between 9 and 12 pounds – might be in trouble.
A new study published today in Scientific Reports found that climate change will have a dramatic impact on the Antarctic homes of Adélie penguins. The study predicts that 30% of their population could be gone by the year 2060, and as much as 60% of the population will disappear by the end of the century.
The researchers based these predictions on satellite observations of sea surface temperature, sea ice and bare rock locations, penguin population estimates, and the various levels of warming expected over the next century by the Intergovernmental Panel on Climate change.
Adélie penguin colonies breed around the continent in October in rocky onshore areas, building nests with small stones. In early spring, when ice sheets began to break up, the penguins waddle over long distances (sometimes as far as 31 miles) from their nest to open water to hunt for fish.
Geological records show that these penguins have long been affected by shifts in climate for nearly 45,000 years, with the expansion and melting of glaciers affecting their distribution and breeding grounds. Previously, the melting of some glaciers was beneficial, allowing the penguins to return to rocky breeding grounds that had once been inaccessible. But these benefits of warming have now reached a tipping point.
While these little birds do not thrive when it is too cold, recent population trends suggest they also do not thrive when there is excessive warmth. Warming sea surface temperatures are likely to create conditions in which the penguins will simply not be able to rear chicks.
- Thomson Reuters
Researchers report that the climate change impact on the birds is likely to be site-specific, with some regions of the continents more affected than others. For example, colonies are already in decline (by almost 80%) across the West Antarctic Peninsula, which is one of the most rapidly warming places on earth. This region has had the most years with warmer than normal sea surface temperatures, called “novel climate,” and climate models predict this trend will continue in the future.
Still, there is a little hope for the Adélie penguins. Because the effects of warming climates are likely to be site specific, it is possible that there will be refugia areas, or areas that have a relatively unaltered climate. One such place is Cape Adare, a peninsula far south in East Antarctica. This suggests that the populations of penguins that survive will be concentrated in the south over the next century.