It is also the only island to date with a population estimate (285,000-305,000) derived from a ground survey of the island. Though they are not especially uncommon, scientists have been concerned that their Antarctic population has been on a steady decline for the last 40 years.
The numbers were toted up by humans counting the birds on land, and via automated tallies of images taken by unmanned aerial vehicles.
The first bird census of the Danger Islands unearthed over 750,000 Adelie breeding pairs, more than the rest of the area combined, the team reported in the journal Scientific Reports. Governments have a huge opportunity this year to create an Antarctic Ocean Sanctuary, which would put nearby waters off-limits to expanding industrial fishing vessels that are targeting the major food source for penguins and other marine life: the small, shrimp-like, krill.
Elsewhere in Antarctica where the climate is more volatile, penguin colonies are in decline.
The research team's December 2015 visit coincided with what is mid-summer in Antarctica, and at the islands, the average temperature hovered around 32 degrees, just at freezing, he said. They reconfigured a commercial quadcopter drone to fly over the islands taking one photo per second, and those images were were analyzed by neural network software.
'We were... very lucky to have a window of time where the sea ice moved out and we could get a yacht in, ' said Lynch.More news: Stephen Colbert Asks Omarosa Why We Will Not Be Okay Under Trump
It could also help them understand what is causing other populations to decline when these penguins are thriving. Finally getting into the Danger Islands and counting the penguins shows how robust populations are where the ice is intact'. "The Danger Islands are hard to reach, so people didn't really try that hard", team-member Dr Tom Hart from Oxford University, UK, told BBC News.
An accurate update on the size of the population of this supercolony also provides an invaluable benchmark for future change, noted Jenouvrier.
A drone image of penguins in the Danger Islands.
Located off the Antarctic peninsula's northern tip, these islands are both incredibly remote and surrounded by thick sea ice.
"We want to understand why".
A breakthrough discovery of this scale offers ecologists hope: Even in the age of Google Earth, maybe we don't know our planet as well as we think we do.
"And the sheer scale of what we saw, gasped, said Dr".