Adélie penguins are sentinels of a changing climate in Antarctica. Thanks to you, we can work to understand the challenges they face

Benjamin Dupuis, marine predator researcher and PhD student shares his field notes from d'Urville research station in Antarctica.

By the time I arrived at Terre Adélie in early November, the penguins were already building their pebble nests. With around 40,000 breeding pairs on the archipelago, we can’t monitor all of them, so we follow just under 100. We attach small trackers to the birds’ backs so we can record their trips to the sea and collect data on their diving behaviour. I study the Adélies’ movements during the breeding season to understand which areas of ocean are the most important for them. This will help us to predict how the penguins will be affected by their changing environment. The penguins have already had to deal with climatic challenges: in 2022, the ice broke up early and we had an unusual amount of rain and snow for the time of year. This created tricky conditions on land. I saw some penguins struggling to find the perfect stones they needed to build their nests due to a thick blanket of snow where there’s normally bare ground. When they did manage to find some pebbles, they were faced with the task of building a nest on top of the snow – not an easy feat. Their troubles didn’t end there as mild temperatures then melted the snow, soaking their eggs. Sadly, a lot of penguins’ eggs got chilled and failed to hatch. Some days, the snow was so thick it would cover the nesting Adélies up to their necks. Just looking at them made me feel cold, but this icy blanket isn’t a problem for penguins. Their thick, double layer of feathers traps warm air close to their skin, and their constant preening spreads a waterproofing oil across their plumage. A thick layer of fat adds extra insulation. Penguins also have an adaptation called counter-current exchange, where blood in the arteries supplying their feet and flippers heats up the blood returning to the rest of their body in nearby veins. Thanks to these amazing adaptations, they’re able to swim in icy water that’s -2ºC!

Adelie penguin (Pygoscelis adeliae) taking a dive, Antarctic Peninsula, January 2018
© WWF-Aus / Chris Johnson

Around mid-December, the Adélies’ chicks began to hatch. Newly hatched birds are susceptible to the cold and must be brooded around the clock by their parents, but the unusually wet weather meant families were faced with an even greater challenge. If the chicks’ downy feathers become soaked, they lose their insulating ability, which can mean freezing to death in this unforgiving landscape. Over the next few weeks, the chicks grew rapidly and became more independent, taking their first steps beyond the nest and beginning to explore. Before we knew it, they were big enough to be left in creches while both parents foraged at sea, only returning to the colony to feed their young. As the chicks began to replace their down with adult feathers, I’d often see parent birds being chased by hungry, rather punk-styled moulting chicks. It was hilarious! The recent high levels of snow and rain have made this breeding season particularly difficult, but climate change means these kinds of conditions are only going to become more common. By understanding the threats penguins are facing now, we can predict how future changes to their environment might affect them – and identify ways to help. And by protecting penguins, we're also helping to safeguard Antarctic biodiversity as a whole. It’s all thanks to your support that this vital research is possible.

A raft of Adelie penguins (Pygoscelis adeliae) on an ice formation in Antarctic Peninsula, January 2018.
© WWF-Aus / Chris Johnson