Bird flu is bad -- for elephant seals

 

I hate to be the bearer of bad news -- in fact, I hate to be the reader of bad news.

Reading about what H5N1, otherwise known as avian/bird flu, has done to populations of pinnipeds (seals, sea lions, elephant seals) is definitely reading about bad news.

It's downright scary. And the BBC headline doesn't make it less so.

'It was a horrible scene to witness': How bird flu has decimated elephant seal populations

"In 2023, however, it was impossible to know the full number of dead adults, as additional deaths could have occurred at sea. Or how many females had become pregnant after the outbreak. So at the end of 2024, in the following breeding season, Campagna and colleagues from WCS [World Conservation Society] along with scientists from the University of California, Davis and the Argentinian research agency Conicet – returned to survey the beaches once again.

Their results, released at the end of September 2025 and seen by the BBC, reveal that the elephant seal population at Peninsula Valdés decreased by 60% overall after the bird flu outbreak. According to researchers, this population drop fits the criteria of the International Union for Conservation of Nature (IUCN) to push a species population once considered of "Least Concern" to "Endangered". While the official change of the species conservation status hasn't happened yet, Uhart believe it will soon.

According to their latest findings, the total number of alpha males dropped 43% (from approximately 450 to 260), while female adults decreased by 60% (from about 12,000 to 4,800), compared to pre-pandemic seasons. The annual offspring was also slashed by nearly two-thirds, from around 14,000 to only 5,000.

"Before 2023, it was impossible to think that a healthy population like the one in Peninsula Valdés could become endangered from one year to another," says biologist Valeria Falabella, seashore conservation director at WCS Argentina. "This is a warning," she adds, noting that climate change brings additional risks and uncertainties for the species."

There are a lot of warnings out there in the wild world. It doesn't seem to me enough people are heeding them.

 

It's definitely something to shout about