Over the final three years, a extremely deadly type of avian influenza has whipped all over the world, felling birds in Europe, Africa and Asia earlier than leaping throughout the ocean and setting off the worst chicken flu outbreak in United States historical past.
Last fall, the virus, generally known as H5N1, lastly arrived in South America. It raced shortly down the Pacific coast and killed wild birds and marine mammals in staggering numbers. Peru and Chile alone have reported greater than 500,000 useless seabirds and 25,000 useless sea lions, in line with a new report, which was printed final week by OFFLU, a world community of flu specialists.
Now, scientists are apprehensive that the virus will make its approach to Antarctica, considered one of solely two continents — together with Australia — that haven’t but been hit by the pathogen. “The negative impact of this virus on Antarctic wildlife could be immense — likely worse than that on South American wildlife,” the report warns.
More than 100 million birds breed in Antarctica and on the islands close by, and plenty of marine mammals swim within the surrounding waters. Some of these species, together with the distinctive emperor penguin and Antarctic fur seal, crowd collectively in giant colonies. “And that could be a recipe for disaster,” mentioned Dr. Ralph Vanstreels, a researcher at a Latin American wildlife health program on the University of California, Davis, and an creator of the brand new report. “We could be looking at a very high death toll.”
This chicken flu variant, which emerged in 2020, has brought about monumental outbreaks on poultry farms, ensuing within the deaths of nearly 60 million farmed birds within the United States alone. But in contrast to earlier variations of the virus, it has additionally unfold broadly in wild birds and routinely spilled over into wild mammals.
The virus first appeared in South America in October 2022, spreading from Colombia right down to Chile in simply three months. “As soon as it started moving south, it did so very, very rapidly,” mentioned Dr. Marcela Uhart, who directs the U.C. Davis Latin American wildlife health program and is an creator of the OFFLU report.
The casualties are tough to tally as a result of many contaminated animals had been in all probability by no means detected, scientists mentioned, and never all the useless animals that did flip up had been examined for the virus. But a whole lot of hundreds of useless seabirds, together with boobies, cormorants and gulls, had been reported in South America. The losses accounted for 36 p.c of Peru’s inhabitants of Peruvian pelicans and 13 p.c of Chile’s Humboldt penguins, in line with the report.
South American sea lions additionally died by the hundreds, representing 9 p.c of the inhabitants in Peru and Chile. (Scientists are nonetheless undecided precisely how marine mammals are contracting the virus or whether or not it’s spreading readily amongst them.)
The virus has continued to maneuver south. In June, it turned up in a South American sea lion within the far south of Chile, simply 670 miles from the Antarctic Peninsula. Some birds routinely wander between South America and Antarctica, feeding in each areas. Others will make their approach to their Antarctic breeding websites as spring arrives within the Southern Hemisphere, doubtlessly bringing the virus with them.
Antarctica has by no means had an outbreak of extremely pathogenic chicken flu earlier than and its residents are prone to have few immune defenses in opposition to the virus. “The populations are completely naïve,” mentioned Dr. Thijs Kuiken, a veterinary pathologist at Erasmus University Medical Center within the Netherlands and an creator of the brand new report. “The worry is that the first time that it goes through, it will really have a high impact in terms of rate of mortality.”
Many of the area’s birds, together with emperor penguins and sooty shearwaters, are already dealing with different threats, from sources together with local weather change, the fishing trade or different human actions. Some species, just like the southern pintail and the Macquarie shag, are restricted to only a few islands. “So if you were to get an outbreak in those islands, basically the whole species collapses,” Dr. Vanstreels mentioned.
Local marine mammals might be in danger, too. Although the Antarctic fur seal can vary broadly, 95 p.c of the inhabitants lives round only one island, making it susceptible to an outbreak.
At this level, the virus is so widespread that it will not be attainable to cease it from reaching Antarctica. “At the moment, there’s nothing we can do to prevent it,” Dr. Kuiken mentioned. “So it’s important in the coming months to be as alert as possible.”
It might be important to watch wild populations to be taught extra about how the virus is spreading, what species is likely to be most in danger and what conservation actions is likely to be wanted to assist them get well, scientists mentioned. “What we’re trying to do is document this really well, trying to understand how the virus is moving to see how we can better protect the species going forward,” Dr. Uhart mentioned.