Good news! Millions more Adélie penguins may be marching across Antarctica than earlier counts suggested.
Nearly six million of the tuxedoed penguins may live in East Antarctica, more than double the previous count of 2.3 million birds, scientists said on Thursday.
The new data is exciting—more penguins!!! However, there are some concerns about the population information from a conservation standpoint, according to the team of Australian, French and Japanese researchers working on the penguin count.
A higher number of penguins suggests that more flightless birds are interacting with humans than previously thought, meaning researchers might need to be more vigilant about protecting breeding grounds. More penguins also means more demand for their prey, krill and fish.
Population-related problems would only compound the bigger threat facing Adélie penguins, and nearly everything else on the planet: climate change. Antarctica’s melting ice will reduce the seabirds’ swath of viable habitat, while warmer and more acidic oceans could hamper their food supply.
By the end of the century, around 60 percent of today’s Adélie colonies may be in decline by 2099 because of climate change, according to a NASA-funded study from 2016.
Yet long-term projections are fairly uncertain, given all the what-ifs, and even current estimates can be off by millions, as Thursday’s study showed.
But wait, how did scientists miss several million adorable penguins? The simplest explanation is that researchers previously only included breeding pairs in their population studies. The baby-makers stay mostly on land between October and February to nest and breed, allowing researchers to take a rough head count.
The non-breeders “are harder to count because they are out foraging at sea, rather than nesting in colonies on land,” Louise Emmerson, a seabird ecologist with the Australian Antarctic Division, said in a news release.
This time, however, the researchers counted both groups of birds. “Our study in East Antarctica has shown that non-breeding Adélie penguins may be as, or more, abundant than the breeders,” she said.
During several breeding seasons, the scientists used aerial and ground surveys, tagging and re-sighting data, plus automated camera images ranging over a more than 3,100-mile stretch of coastline in East Antarctica.
The team estimated 5.9 million Adélie penguins in the region, and between 14 million and 16 million birds globally.
Among the East Antarctica penguin posse, a sizable amount breed near one of the nine permanently occupied research stations in the ice-free areas. Penguins prefer those spots for nesting; they’re also the most ideal areas for research stations, due to ease of resupply.
More than a million birds, or 29 percent of the population, breed within 6.2 miles of a research station, and 44 percent breed within 12.4 miles of a station, said Colin Southwell, a seabird ecologist and lead author of Thursday’s study.
“By identifying significant penguin breeding populations near stations we can better identify which areas may need enhanced protection into the future,” he said in the news release.