In the spring of 2019, scientists declared that the second largest emperor penguin colony in the world had disappeared, following disastrous weather and breeding conditions over the previous three years.
This followed the disappearance of huge colonies of Adelie penguins that had also taken place in recent years. It was a devastating one-two blow, a tragedy for penguin lovers and ornithologists alike. What happened? What has caused these events?
Adelie Penguins and Ironically Thick Ice
There are two kinds of true Antarctic penguins: Adelie and emperor penguins.
The disaster for the Adelie penguins has been caused by global climate change, but while we might usually visualize that change causing ice to melt and thin, in this case, it is thicker ice that has caused the problem.
In 2010, thinning sea ice caused a tongue of a glacier (the Mertz glacier) to break off, and an iceberg the size of the country of Luxembourg broke away. This event caused massive changes in ocean currents and affected the way that ice formed in the whole area.
Ice began to pile up in much bigger amounts in the area where the penguins had traditionally laid their eggs and hatched their chicks. This caused a significant problem. The thicker ice meant that adult penguins had to travel 62 miles more than usual in search of open water so they could catch food to eat for themselves and to take back to their chicks.
While the parents were gone, the chicks were defenseless, hungry, and exposed to the elements, as penguin down is not waterproof for some time after birth. All the extra time that parents were away meant that the chicks died.
Scientists monitoring the situation have been devastated by the scenes, which have been very moving: the eggs and chicks, left behind, dying alone on the ice.
In 2017, scientists found that of all the eggs laid and the chicks hatched, only two baby Adelie penguins survived.
Emperor Penguins and Thin Ice
If the events of the previous time had not been bad enough, additional tragedy struck in 2016 and continued for the next three years.
This time, it was about thin ice, not thick.
Emperor penguins lay their eggs and hatch them on ice shelves, one of which is in Antarctica’s Weddell Sea in a place known as Halley Bay. As with the Adelie penguins, the Halley Bay colony in the Weddell Sea usually contained somewhere in the neighborhood of 25,000 breeding pairs of penguins.
In 2016, however, tragedy struck on the breeding shelf as the ice, weakened by climate change, broke and fell, drowning tens of thousands of newborn baby penguins overnight.
As if this first ice shelf collapse was not enough to decimate the colony, the tragedy repeated in 2017 and 2018, with the Antarctic ice too thin, apparently, to hold the weight of the thousands of penguins who had arrived for breeding season to lay their eggs and raise their chicks.
Emperor penguins are the tallest and heaviest of all penguin species and need reliable and sturdy patches of ice on which to raise their young.
Each time, the newly hatched chicks were dropped into the sea before they were ready to swim or survive and were drowned.
In 2019, researchers from the British Antarctic Survey, working from satellite photos, noted first that a large iceberg (newly broken off due to ocean warming) was about to disrupt the site. They also noted that no penguins were even trying this year to re-establish a colony at the site.
For this reason, the scientists decided to declare that the Halley’s Bay colony, the second largest emperor penguin colony in the world, was gone.
What Does this Mean?
As the National Geographic Society notes, Antarctica could indeed lose all of its penguins. Penguins require very specific conditions for laying their eggs and hatching and raising their young. We have likely reached the point where we need to accept that widespread extinctions of many species are inevitable.
Some continue to hope, however, that many of humanity’s favorite animals will adapt to changing climate conditions and find ways to manage as the world and the climate change around them. We will have to wait and see what the future, our decisions, and our climate bring.