Reported by NPR World
A small group of Adélie penguins return to their colony. A mega-colony of these penguins was hit by a big die-off in early 2024. Ralph Vanstreels hide caption
Sailing toward the Danger Islands, Dr. Ralph Vanstreels had a good idea of what he might find: A lot of dead Adélie penguins.
It was March 2024 and a virus had been sweeping through the area, leaving deceased birds in its wake.
More from the original report
Vanstreels got the crime right but the culprit wrong. There were dead penguins but a virus was not to blame.
As his vessel pulled up to a landing ramp on one of the islands — located just off the Antarctic Peninsula — Vanstreels and his fellow researchers immediately noticed bumps in the snow.
"Was each bump a rock or was it a carcass? We had to do quite a bit of intensive searching [through the snow]," says Vanstreels, who is based in Argentina and is a wildlife veterinarian with the University of California, Davis.
The team ultimately found more than 537 penguin carcasses on just the ramp, which he estimates was about the size of an airport runway.
There were many more carcasses elsewhere on the Danger Islands, which are home to two mega colonies for penguins. The researchers estimate there were thousands of dead Adélie penguins and other species of birds. But they had to work quickly and couldn't do a complete count, Vanstreels says.
A view of the Adélie penguin colony at Beagle Island, one of the Danger Islands. A few penguin carcasses are scattered on the rocks. Ralph Vanstreels hide caption
"You cannot stay there very long because you might be locked down with an iceberg blocking your way out," he says.
As the team has pieced together this tragic penguin mystery, Vanstreels says, the case holds broader lessons for tracking the spread of diseases globally.
Now let's time jump to Australia a few months ago for another bird disease conundrum.
In June, H5N1 — high pathogenicity avian influenza also known as bird flu — arrived in mainland Australia. Up until that point, Australia had been the…