Over the past three years, a extremely deadly type of avian influenza has whipped around the globe, 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.
Final fall, the virus, often called 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 lifeless seabirds and 25,000 lifeless sea lions, in keeping with a brand new report, which was printed final week by OFFLU, a worldwide community of flu specialists.
Now, scientists are apprehensive that the virus will make its approach to Antarctica, one in all solely two continents — together with Australia — that haven’t but been hit by the pathogen. “The destructive influence of this virus on Antarctic wildlife may very well be immense — probably worse than that on South American wildlife,” the report warns.
Greater than 100 million birds breed in Antarctica and on the islands close by, and plenty of marine mammals swim within the surrounding waters. A few of these species, together with the distinctive emperor penguin and Antarctic fur seal, crowd collectively in massive colonies. “And that may very well be a recipe for catastrophe,” stated Dr. Ralph Vanstreels, a researcher at a Latin American wildlife well being program on the College of California, Davis, and an creator of the brand new report. “We may very well be taking a look at a really excessive dying toll.”
This chicken flu variant, which emerged in 2020, has brought about huge outbreaks on poultry farms, ensuing within the deaths of practically 60 million farmed birds in the US alone. However not like 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 quickly because it began shifting south, it did so very, very quickly,” stated Dr. Marcela Uhart, who directs the U.C. Davis Latin American wildlife well being program and is an creator of the OFFLU report.
The casualties are tough to tally as a result of many contaminated animals had been most likely by no means detected, scientists stated, and never all the lifeless animals that did flip up had been examined for the virus. However tons of of hundreds of lifeless seabirds, together with boobies, cormorants and gulls, had been reported in South America. The losses accounted for 36 % of Peru’s inhabitants of Peruvian pelicans and 13 % of Chile’s Humboldt penguins, in keeping with the report.
South American sea lions additionally died by the hundreds, representing 9 % 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 more likely to have few immune defenses in opposition to the virus. “The populations are utterly naïve,” stated Dr. Thijs Kuiken, a veterinary pathologist at Erasmus College Medical Heart within the Netherlands and an creator of the brand new report. “The concern is that the primary time that it goes by, it’ll actually have a excessive influence by way of fee of mortality.”
Most 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 business or different human actions. Some species, just like the southern pintail and the Macquarie shag, are restricted to just some islands. “So for those who had been to get an outbreak in these islands, mainly the entire species collapses,” Dr. Vanstreels stated.
Native marine mammals may very well be in danger, too. Though the Antarctic fur seal can vary broadly, 95 % of the inhabitants lives round only one island, making it weak to an outbreak.
At this level, the virus is so widespread that it will not be potential to cease it from reaching Antarctica. “In the meanwhile, there’s nothing we will do to forestall it,” Dr. Kuiken stated. “So it’s necessary within the coming months to be as alert as potential.”
It will likely be vital to watch wild populations to study 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 stated. “What we’re attempting to do is doc this very well, attempting to know how the virus is shifting to see how we will higher defend the species going ahead,” Dr. Uhart stated.
