Serendipity helped scientists track down a “supercolony” of Adelie penguins hidden on an isolated archipelago in Antarctica, and the story of how they located the birds is just as baffling as the find itself. The massive colony dwells on a remote group of nine rocky islands called Danger Islands and is so big it was literally spotted from space, reports BBC News.
The discovery is detailed in a paper published today (March 2) in the journal Scientific Reports and belongs to researchers from the Woods Hole Oceanographic Institution (WHOI), who set about exploring the secluded area in December of 2015 after coming across some intriguing photos taken by the American Landsat spacecraft.
The images taken from space had captured significant guano stains on the archipelago rocks, prompting scientists to believe a large colony of penguins could have gone unnoticed in the area. This rekindled interest in the Danger Islands, which “weren’t known to be an important penguin habitat,” study co-author Dr. Heather Lynch said in a WHOI news release.
Dr. Lynch, who is a professor of ecology and evolution at Stony Brook University in New York, was also the one to stumble upon the NASA satellite imagery back in 2014, together with Mathew Schwaller, a scientist at NASA Goddard Space Flight Center.
The pair enlisted the help of WHOI seabird ecologist Stephanie Jenouvrier; Michael Polito, an assistant professor at Louisiana State University; and Dr. Tom Hart, from Oxford University, U.K. to investigate their findings. The team boldly set off on an expedition into the remote islands and found a “hotspot” of Adelie penguins previously unknown to science.
“It’s a classic case of finding something where no-one really looked,” Dr. Hart said in a statement for BBC News.
He explained that the Danger Islands, located off of the Antarctic Peninsula’s northern tip in the northwest Weddell Sea, are so inaccessible that they usually make explorers think twice before deciding to set foot in the area. In fact, these islands are generally avoided by ships due to their “treacherous waters” and thick sea ice, notes the WHOI news release.
“This is called the Danger Islands for a reason,” said Dr. Lynch in a statement.
“The area is covered by heavy sea ice most of the year, and even in the height of summer it is difficult to get into this region to do surveys,” she specified.
Nevertheless, the undeterred researchers braved these daunting conditions and, by a miraculous twist of fate, ended up uncovering a staggering total of 751,527 pairs of Adelie penguins nesting on the rocky archipelago. This amounts to more than 1.5 million individuals living undisturbed and undetected in the pristine islands.
According to Dr. Lynch, this momentous discovery was made possible by “a window of time where the sea ice moved out” enough so that the team could get a yacht to the islands, News.com.au disclosed.
The “supercolony” was so massive that it couldn’t be tallied just by hand-counting alone. It took a collage of drone footage and a neural net counting program that produced 2D and 3D maps of the area to gauge the enormous extent of the colony.
Spectacularly, the study revealed that the hidden sanctuary in the Danger Islands hosts more Adelie penguins than the whole Antarctic Peninsula. In addition, it also “includes the third and fourth largest Adelie penguin colonies in the world,” the researchers write in their paper, which they describe as “the first complete census of Pygoscelis spp. penguins in the Danger Islands.”
Moreover, the team also discovered two other species of penguins nesting on the distant archipelago. Their report showed the Danger Islands are home to roughly 100 pairs of Gentoo penguins and around 27 pairs of Chinstrap penguins.
Perhaps the most striking thing about this “unexpected penguin metropolis,” as LiveScience called it, is the fact that their isolation has kept the Adelie penguins safe from the threats that have been plaguing penguin populations in other areas of Antarctica.
Less than 100 miles to the west of the peninsula, the populations of Adelie penguins have plummeted over the last four decades, decreasing by a whopping 70 percent, states News.com.au.
“Not only do the Danger Islands hold the largest population of Adelie 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,” Polito points out.
Jenouvrier also chimed in on the matter, revealing that the team is hoping to figure out what made the Danger Island penguins fare so much better than their western counterparts.
“Is it linked to the extended sea ice condition over there? Food availability? That’s something we don’t know.”
This becomes increasingly important from a conservationist standpoint, as the secret “supercolony” could help scientists understand more about population dynamics and “the effects of changing temperature and sea ice on the region’s ecology,” shows the in the WHOI news release.
As a matter of fact, the study authors are proposing that the Danger Islands should be taken into “special consideration” when the officials designate the marine protected areas in the region.
On a separate note, the NASA collaboration that sparked this discovery has also provided the scientific community with an online penguin map that keeps track of Antarctic penguin populations. The project is based on a tool called Mapping Application for Penguin Populations and Projected Dynamics (MAPPPD), which was developed by Dr. Lynch and Schwaller two years after they discovered the NASA satellite photos that pinpointed the presence of penguins in the Danger Islands.
MAPPPD comprises “data for approximately 1,300 historical and current surveys in over 700 sites around the Antarctic continent,” based on both satellite imagery and published literature, Dr. Lynch detailed in a NASA news release from 2016.
The MAPPPD penguin map “is the first of its kind” and enables citizen scientists “to understand how environmental change, fishing, and tourism may be affecting Antarctica’s iconic birds,” shows the 2016 news release.