Estimates are that the current epidemiological outbreak of the H5N1 type virus (highly pathogenic "bird flu"), which began in 2021, has caused the death of millions of wild birds and thousands of mammals worldwide, the "Guardian" reported.
A polar bear has died from bird flu as the highly contagious H5N1 virus spreads to the most remote parts of the planet.
The death was confirmed in December by the Alaska Department of Environmental Protection. "This is the first reported case involving a polar bear ever," said Dr. Bob Gerlach, Alaska's state veterinarian.
Gerlach said the bear probably fed on the carcasses of infected birds.
Polar bears are listed on the International Union for Conservation of Nature's (IUCN) Red List as a "threatened" species, mainly due to declining sea ice.
"It's possible that more bears died unnoticed because they usually live in remote areas with few people," Gerlach said. "You really depend on the people who are there or the biologists who are involved in wildlife monitoring," he said.
The current outbreak of the highly contagious H5N1 variant, which began in 2021, is believed to have killed millions of wild birds. Globally, thousands of mammals have also died from the virus, including black and brown bears. Among the species that have died from the virus in Alaska in recent months are bald eagles, foxes and cats.
"It was in Antarctica and now it's appeared in the Arctic in mammals, it's terrifying," Diana Bell, emeritus professor of conservation biology at the University of East Anglia, told the Guardian.
"Yet I am not surprised, in the last few years the list of dead mammals has become colossal. There is now such a wide range of raptors and carnivorous mammals affected that it is not just a poultry disease.
"When it affects a big, iconic species like the polar bear, people suddenly sit up and listen, or at least I hope they do. We already have a biodiversity pandemic and it's called H5N1 because it's killed a lot of birds and mammals."
The first known cases of H5N1 were found in the Antarctic region in October among brown skuas (a type of large seabird) on Bird Island, off South Georgia. Two months later, hundreds of fur seals were found dead. Several other locations also saw increased mortality of seals, lalugers, and brown skuas.
Scientists warn that the highly contagious virus could lead to "one of the greatest environmental catastrophes of modern times" if it reaches remote penguin populations. The virus continues to spread south into the Antarctic region.
According to the latest update on the Scientific Committee for Antarctic Research (SCAR) website, further tests are currently pending. "It doesn't bode well," said Dr Megan Dewar, head of SCAR's Antarctic Wildlife Health Network.
Dewar co-authored the risk assessment, which found that many Antarctic animals are at risk, including gulls, lalugers, seals and sea lions.
She said: "The analysis showed an increased risk of HPAI (highly pathogenic avian influenza) in Antarctic species in 2023 or 2024 in the Antarctic Peninsula region, and that is exactly what we are seeing."
Ecosystems in polar regions are particularly vulnerable to bird flu because they are home to many animals that are found nowhere else in the world and have never been exposed to such viruses. In addition, these areas are among the most affected by climate change. /BGNES