H5N1 Causes Die-off of Antarctic Skuas, a Seabird
Skua Deaths Mark First Wildlife Mortality Due to Avian Flu on Antarctica
More than 50 skuas in Antarctica died from the high pathogenicity avian influenza virus H5N1 in the summers of 2023 and 2024, marking the first documented die-off of wildlife from the virus on the continent. That is confirmed for the first time in a study led by Erasmus MC in The Netherlands and the University of California, Davis. It published this week in the Nature journal Scientific Reports.
A relative of gulls, skuas are predatory, large brown birds living mostly in polar and subpolar environments. Similar to raptors, they play an important ecological role as scavengers. That role could position them to further spread the virus across Antarctica, the report notes.
Scientists previously detected the virus in a kelp gull and two skuas in Antarctica found dead in January and February 2024. However, avian flu had not been confirmed as the cause of their deaths.
“We knew there were animals with the infection, but this is the first study to show they died of the viral infection,” said co-senior author Ralph Vanstreels, a wildlife veterinarian with the UC Davis One Health Institute within the Weill School of Veterinary Medicine. “It’s an important distinction in the early days of an outbreak.”