During the last 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 hen flu outbreak in United States historical past.
Final fall, the virus, often known as H5N1, lastly arrived in South America. It raced rapidly 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 line with a brand new report, which was revealed final week by OFFLU, a worldwide community of flu consultants.
Now, scientists are nervous that the virus will make its solution to Antarctica, one in every of solely two continents — together with Australia — that haven’t but been hit by the pathogen. “The detrimental affect of this virus on Antarctic wildlife could possibly be immense — possible 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 lots 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 giant colonies. “And that could possibly 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 could possibly be taking a look at a really excessive loss of life toll.”
This hen flu variant, which emerged in 2020, has precipitated monumental outbreaks on poultry farms, ensuing within the deaths of almost 60 million farmed birds in the USA alone. However not like earlier variations of the virus, it has additionally unfold extensively 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 transferring 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 the entire lifeless animals that did flip up had been examined for the virus. However a whole bunch of 1000’s 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 line with the report.
South American sea lions additionally died by the 1000’s, representing 9 % of the inhabitants in Peru and Chile. (Scientists are nonetheless unsure 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 solution 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 hen flu earlier than and its residents are more likely to have few immune defenses towards the virus. “The populations are utterly naïve,” stated Dr. Thijs Kuiken, a veterinary pathologist at Erasmus College Medical Middle within the Netherlands and an creator of the brand new report. “The concern is that the primary time that it goes by way of, it is going to actually have a excessive affect when it comes to price of mortality.”
Lots 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 should you had been to get an outbreak in these islands, mainly the entire species collapses,” Dr. Vanstreels stated.
Native marine mammals could possibly be in danger, too. Though the Antarctic fur seal can vary extensively, 95 % of the inhabitants lives round only one island, making it susceptible to an outbreak.
At this level, the virus is so widespread that it is probably not attainable to cease it from reaching Antarctica. “In the meanwhile, there’s nothing we are able to do to forestall it,” Dr. Kuiken stated. “So it’s vital within the coming months to be as alert as attainable.”
It is going to be essential to observe wild populations to be taught extra about how the virus is spreading, what species is perhaps most in danger and what conservation actions is perhaps wanted to assist them recuperate, scientists stated. “What we’re attempting to do is doc this very well, attempting to grasp how the virus is transferring to see how we are able to higher defend the species going ahead,” Dr. Uhart stated.
