‘Supercolony’ of 1.5m penguins detected on remote island causes flap among scientists
YOU might think it would be difficult to miss one and a half million penguins. However, after living in obscurity on the Danger Islands off the Antarctic peninsula, a “supercolony” of Adélie penguins has been discovered by scientists.
The birds were detected on the rocky and remote islands after patches of their excrement were picked up by Nasa satellites in 2014, and a team of scientists later calculated the vast number using drone technology.
The team launched an expedition in December 2015 to the Danger Islands, which were so-called in 1842 by James Clark Ross, the explorer, for being thickly encrusted in ice.
Dr Tom Hart, of Oxford University, one of the expedition party, told The Daily Telegraph: “This is the biggest colony discovered recently. It is a huge number of penguins.
“The weirdest, most surprising and incredible thing is that, in this day and age, something so big can go unseen.”
The discovery comes after thousands of Adélie penguin chicks died between 2010 and 2017 due to mass starvation, in what French scientists described as a “catastrophic breeding failure” caused by unusually thick sea ice which forced their parents to forage further for food. As a result, only two chicks out of 18,000 pairs of Adélie penguins in east Antarctica survived the early 2017 breeding season.
The newly-discovered supercolony had managed to go undetected for so long because of the remoteness of the islands and the treacherous waters that surround them, said Heather Lynch, associate professor of ecology and evolution at Stony Brook University, New York, and lead author of the study.
“Until recently, the Danger Islands weren’t known to be an important penguin habitat,” she said. However, all that has changed.
Once the team of scientists had arrived on the islands, they used a drone to take aerial images and gather infor- mation on the number of penguins in the colony. The drones allowed scientists to survey the island in a grid while taking one picture per second.
“You can then stitch them together into a huge collage that shows the entire land mass in 2D and 3D,” said Hanumant Singh, professor of mechanical and industrial engineering at Northeastern University, Boston, Massachusett, who developed the drone’s imaging and navigation system. Specialist software helped them comb through the images to search for penguin nests.
What this revealed was that 751,527 pairs of Adélie penguins live on the islands.
The study, published in the journal Scientific Reports, also found the population of Adélie penguins on the Danger Islands has been stable since 1959, despite the effects of climate change.
“Not only do the Danger Islands hold the largest population of Adélie penguins on the Antarctic peninsula, they also appear to have not suffered the population declines found along the western side of Antarctic peninsula that are associated with recent climate change,” said Prof Michael Polito, from Louisiana State University, who co-authored the study.
Dr Hart added: “I think people have got used to knowing where things are, so they stop looking. The penguins have been there all along.
“This is not new to the penguins – they are quite happy living their lives out there. This is new to us and it is just a fact that we have overlooked them.”