What can hundreds of dead penguins tell us about climate change?

A warmer world might be a penguin-less world. 

New research has connected hundreds of mummified penguin carcasses to two disastrous weather events thought to be influenced by climate change.

The study, which was published in the Journal of Geophysical Research – Biogeosciences, warns that these events might foreshadow what’s to come if the Earth continues to get hotter.  

A team of Chinese and Australian researchers found the mummified Adélie penguins under a remarkably thick layer of sediment in Long Peninsula, East Antarctica, which usually has a dry climate. 

Then, using radiocarbon dating, the scientists found that most of the mummified carcasses were from two specific incidents that affected breeding colonies from 750 and 200 years ago.

Hundreds of mummified penguin carcasses scattered across the study site in East Antarctica.

“First of all, the extent of carcasses and abandoned colonies struck us,” co-author Yuseong Gao told the American Geophysical Union. “Then we were surprised by the consistent dates of the mummies. We had expected a much larger range of dates.”

Lead researcher Liguang Sun also explained to LiveScience that it’s actually not strange to find a bunch of dead Adélie penguins with their feathers and bones intact. 

“But it is very rare to find so many mummified penguins, especially mummified chicks,” Sun told LiveScience.

All of these signs alerted them that something out of the ordinary had occurred. The two instances of unusually thick sediment were evidence to the researchers that a lot of water flowed over the area in a short amount of time. 

Since penguin chicks do not develop waterproof feathers until a later stage of development, a particularly wet or snowy season would put them in danger of getting hypothermia and dying — which is why scientists believe they found the large number of dead chicks in the two breeding colonies. 

A closeup of a mummified penguin from the 750 years ago.

The weather event they suspect to be the cause is called zonal wave 3 (ZW3), which produces near-shore ice and adds a lot of moisture to the atmosphere. 

Research showed that this meteorological pattern became more frequent in the late 20th Century due to an increase in greenhouse gas emissions.

Since the world hasn’t done enough to curb our collective greenhouse gas emissions, researchers fear that ZW3’s will become more frequent than ever before and penguin populations will continue to face unfavorable conditions that will jeopardize the survival of the populations. 

This particular breed of Antarctic penguins have seen a slough of catastrophic breeding seasons recently. 

In 2017 all but two penguins from a colony of 40,000 died from starvation. Earlier that year, only two chicks from a colony of 18,000 breeding penguins survived. That same colony lost every chick in 2013. 

Scientists overwhelmingly point to global warming for the cause of these events and are encouraging international organizations to adapt new strategies that would better protect the species.