Bird flu has hit uncomfortably close to home in recent months. Public health experts have detected nearly five dozen known infections H5N1 avian influenza virus in humans in the usa Dairy farmers are approaching their full year to the virus in their herds. And more than 100 million birds in US poultry farms have been lost to the pathogen or killed in attempts to stop its spread since February 2022.
Meanwhile, the spreading strain of the H5N1 virus, known as clade 2.3.4.4b, has also infiltrated ecosystems around the world, wreaking havoc that has largely been forgotten. Millions of individual wild animals of hundreds of species—wild parakeets and penguins, otters and owls, ducks and dolphins—have died on every continent except Australia, including in some of the cleanest places monitored by scientists. Understanding the true scale of bird flu in the wild is more of a guesswork compared to scientific estimates of its impact on domesticated species.
“Wild birds often die in inconvenient places, and it takes people’s time to respond to them, or to count them,” says Michelle Wille, a disease ecologist at the University of Melbourne. “On the contrary, farmers have a specific number of birds in their shelter. So it’s an effort.”
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Where this effort has been made, the results have been grim, revealing a worldwide wave of H5N1 deaths. In South Africa in 2021, monitors counted 20,686 dead cormorants infected with bird flu. In 2022, scientists counted 16,873 dead adult seabirds called Sandwich Terns in the breeding grounds of northwestern Europe. Twenty one massive California condor— precious individuals in a population of less than 600 animals — died in Arizona and Utah in early 2023. 96 percent of elephant seal pups died on some beaches in Argentina that same year, suggesting the regional death toll may be higher. 17,000 animals.
Those elephant seals had a particularly disturbing pair of developments. The virus can and has been shown to affect large numbers of mammals rapidly approaching the Antarctic regionHome to some of Earth’s most beloved ecosystems and animals.
“As it continued south and into South America, that was when the alarm bells were ringing for us,” says Ash Bennison, a marine ecologist at the British Antarctic Survey, who says he started to worry about the threat of H5N1. region in early 2022, almost two years before the virus reached Antarctica.
One area of concern was South Georgia Island, a rugged landscape full of wildlife, located 900 kilometers from the tip of the Antarctic Peninsula, surrounded by several smaller islands. “The Alps are often described as rising straight out of the water,” says Mark Belchier, marine fisheries ecologist at the British Antarctic Survey and director of fisheries and environment for the government of South Georgia and the South Sandwich Islands. “As the only dry land for hundreds of kilometers, it is a key breeding ground.” Several species of whales are celebrated in its rich waterswhile three species of seagull and four species of penguin and albatross each breed on the island, crowding the coast. Tourists who have the means to reach the remote island also attend. In the last year with available data, more than 26,000 people—including tourists, scientists, and aid workers—visited South Georgia.
One of those people was Theo Allan. Trained as an architectural photographer, he made a lifelong pivot in 2019 when he turned his camera to documenting Antarctic tourist expeditions. “It’s almost like going to Mars, where you don’t have human civilization and nature takes its course,” says Allan. “The size of these icebergs makes you feel like an ant.”
On cruise ship excursions, he and tourists board inflatable boats to get close to shore, racing between icebergs that can collapse at any moment. Even under the best conditions, the work is hard. “The wind is blowing; (there are) snowflakes, snowflakes hitting your face,” he says. “It can be pretty intense.”
Conditions were even more difficult when he arrived in South Georgia in January 2024 for a two and a half month visit. Then he saw evidence that bird flu had hit the region.
Both skuas feed on penguin carcasses, highlighting the role of the Antarctic food chain in the transmission of bird flu.
The first known cases around South Georgia were found in seabirds on Bennison’s Bird Island, on the west end of the main island. (While it’s possible that humans brought the virus to Bird Island, scientists say evidence suggests migrating animals were the likely vector.) In mid-September, researchers observed a young Southern Giant Petrel that appeared ill shortly before its death. They started seeing dead Brown Skuas in early October. Both species are predators catchers—scientists reported that Brown Skuas were feeding on the odd-looking petrel carcass. As the virus spread, most of the petrels were saved, but dozens of skua were found dead. Scientists know that catching sick animals can spread bird flu between species, but Bennison says it’s not clear why the petrels contracted the disease.
“These are animals that get caught in very strange bodies of things like elephant seals, fur seals, so they’re probably already exposed to a huge range of pathogens,” he says of the petrels. “There may be some animals that have certain ecologies, which means they have a heightened immune system, or maybe they have a more relaxed immune system.”
But the minions were just the beginning. Bennison and his colleagues also reported sightings of Gentoo penguins, wandering albatross and dead or dying seals on Bird Island and South Georgia. Where they could, scientists cleaned up the carcasses and sent samples to the UK for testing, eventually confirming that many of the animals had bird flu.
The region is no stranger to wildlife carcasses. “There are always dead and dying animals,” says Sally Poncet, an independent environmentalist who has worked in South Georgia for decades. “That’s what South Georgia is all about; it’s a matter of life and death.” But he noticed that after bird flu arrived, the bodies piled up faster than usual.
King penguins walk past the rotting carcass of an adult tern on the island of South Georgia, in the British overseas territory of South Georgia and the South Sandwich Islands, Antarctica.
Allan also noticed the difference when he arrived in January and started visiting the familiar places. Although he expected to see the effects of the virus, it was a “wonderful experience,” he says, “to see these animals pretty much dead among other living animals that are going to die all along the coast. . . . I don’t know how to put it into words, but it’s hard to witness.” He smelled the difference. , too. “When I was next to some of those carcasses, the stench was very heavy in the air,” Allan says.
Allan was also surprised to see the survivors struggling with the death of their neighbors. For him, the most powerful moment of the season came when he saw a group of king penguins walking inland from the coast. One bird was removed from the group to be placed next to the corpse of another penguin. “The group continued to walk. And then the whole group turned around and looked at this penguin next to the body,” says Allan. “It felt very human.” He particularly remembered the darkest days. covid pandemicWhat he spent in India. “Loved ones would not touch their relatives,” he says. “Some of them wouldn’t even go to get the bodies from the hospital.”
A group of penguins walk away from the corpse of another penguin as one of them stops walking and stands next to the corpse.
Scientists working to understand bird flu and its impact on wildlife have also been forced to deal with the emotional reality of the dead and dying. “It’s pretty sad to know that very little could have been done to minimize transmission or the threat to these animals,” says Bennison. “What you have to do is buckle up and put on your scientist hat and try really hard to collect data to make it worthwhile for animals.”
This year scientists will be able to collect even more data and process it faster. That’s partly because Amandine Gamble, an ecologist at Cornell University, says a team of researchers is in the region to test bird flu samples directly in South Georgia, for example, rather than relying on labs an ocean away.
The test not only diagnoses bird flu, but also helps understand questions such as whether animals are developing resistance to the virus. If so, the discovery would raise hopes that last season’s deaths were an anomaly rather than a persistent threat. Gamble says his initial sense is that poachers are developing resistance, but that’s not the case with Gentoo penguins in both South Georgia and the Falkland Islands, closer to South America, last year.
Allan is back in the south, watching the situation unfold. So far scientists have suggested that wildlife in South Georgia and the surrounding islands are doing better than last year. Bennison says that in late October, he and his colleagues saw two suspicious deaths — compared to about 50, aided by Gentoo penguins, at the same time last year. Many of the island’s nesting birds have already laid their eggs, and seals are returning to establish breeding grounds, he added. Early reports of this season’s elephant seals in South America, however, suggest that this year’s breeding populations may be much lower than usual.
Black albatross skull, remnants of last year’s bird flu outbreak, seen in the Falkland Islands.
Amandine Gamble/Cornell University College of Veterinary Medicine
Scientists say bird flu could affect a different set of species this year, leaving open the possibility that there could be even more deaths in South Georgia’s future. In addition, southern advances that avoided bird flu last year, such as in Antarctica, may run out of luck in the coming months.
Still, Belchier is taking hope that last year’s deaths were mostly among young people rather than middle-aged adults. “These are species that deal with boom-and-bust environmental conditions,” he says. Their populations are structured so that a bad breeding year can wipe out the species. Gamble cautions, however, that he and his colleagues are seeing mature Gentoo penguins in the Falkland Islands, which could suggest a longer-term problem with the population.
Even in the face of more significant losses, South Georgia has a history of resilience, Poncet says. Man killed and introduced several seals and whales the rats wreaked havoc on the local fauna. Each time, with the cooperation of man, species have rebounded. “The wildlife of South Georgia has already seen it all,” he says.
“It’s incredibly resilient,” says Poncet. “Hopefully they will deal with it. Wildlife does it normally, if we leave it alone.’
