Bird flu is sweeping South America. Antarctica could be next.

Over the past three years, a highly deadly form of Avian Influenza Swept across the globe, shooting down birds in Europe, Africa and Asia, then unleashed across oceans worst outbreak Bird flu in American history.

Last fall, the virus was called H5N1finally reached South America.

It spread rapidly along the Pacific coast, killing staggering numbers of wild birds and marine mammals.

only at peru and chile More than 500,000 seabirds and 25,000 sea lions have died, according to a new report last week by OFFLU, a global network of influenza experts.

Now, scientists fear the virus will spread to AntarcticaAustralia is one of only two continents not yet affected by the pathogen.

“The negative impact of this virus on Antarctic fauna is likely to be substantial, possibly more severe than the impact on South American fauna,” the report warns.

More than 100 million birds breed in Antarctica and nearby islands, and many marine mammals swim in the surrounding waters.

Some of these species, such as the endemic emperor penguin and Antarctic fur seal, congregate in large flocks.

“This could spell disaster,” said Dr. Ralph van Stries, a researcher at UC Davis’ Latin American Wildlife Health Program and one of the authors of the new report.

“We could be facing a very high death toll.”

The variant of bird flu that emerged in 2020 caused massive outbreaks on poultry farms, killing nearly 60 million poultry in the United States alone.

But unlike previous versions of the virus, it is also widespread in wild birds and often spreads to wild mammals.

The virus first appeared in South America in October 2022, spreading from Colombia to Chile in just three months.

“Once it starts moving south, it’s moving very, very quickly,” said Dr. Marcela Uhart, director of the Latin American Wildlife Health Program at UC Davis and an author of the OFFLU report.

Scientists say it is difficult to count the number of victims because many infected animals may never be found and not all dead animals that show up are tested for the virus.

But in South America, hundreds of thousands of seabirds, including boobies, cormorants and gulls, have died.

Losses accounted for 36 percent of Peru’s pelican population and 13 percent of Chile’s Humboldt penguin population, the report said.

South American sea lions also died in large numbers, accounting for 9 percent of the populations of Peru and Chile.

(Scientists don’t yet know how marine mammals become infected with the virus, or whether it spreads easily among them.)

The virus continues to spread southward.

In June, it was spotted on a South American sea lion near the southern tip of Chile, just 670 miles from the Antarctic Peninsula.

Some birds frequently wander between South America and Antarctica, feeding in both places.

Others will travel to Antarctic breeding grounds in the southern hemisphere when spring arrives, possibly carrying the virus.

Antarctica has never had an outbreak of highly pathogenic bird flu, and its residents may have poor immune defenses against the virus.

“People are completely naive,” said Dr. Tes Kuiken, a veterinary pathologist at Erasmus University Medical Center in the Netherlands and an author of the new report.

“It’s worrying that the first time this happens, it’s really going to Tremendous influence In terms of mortality.

Many bird species in the region, such as emperor penguins and sand gulls, already face additional threats from sources such as climate change, fisheries or other human activities.

Some species, such as wagtails and cormorants, are restricted to a few islands.

“So if there was an outbreak on these islands, basically the entire species would collapse,” van Struels said.

Native marine mammals may also be at risk.

Although Antarctic seals are widely distributed, 95% of the population lives around a single island, making them vulnerable to outbreaks.

Currently, the virus is so widespread that it may not be able to prevent it from reaching Antarctica.

“Right now, there’s nothing we can do to stop it,” Kuiken said.

“So it’s important that we remain as vigilant as possible over the next few months.”

Monitoring wild populations is critical to learning more about how the virus spreads, which species may be most at risk, and what. conservation action

Scientists say they may need to be helped to recover.

“What we’re trying to do is document this well, try to understand how the virus spreads to understand how we can better protect the species in the future,” Uhart said.

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