Heard Island: A new study has found that bird flu has killed thousands of southern elephant seal pups on Heard Island, one of Australia’s remote sub-Antarctic territories. Researchers estimate that more than 13,000 pups from a population of around 17,000 died after the H5N1 strain spread through colonies since August last year.
The research focused on Heard and McDonald Islands, located about 4,000 kilometres southwest of Australia. The islands support more than one million breeding seabirds and seals, making them an important habitat for wildlife in the region.
Scientists used drone surveys and field investigations conducted between October and January to assess the impact of the outbreak. Samples were collected from nine species, with six testing positive for the H5N1 strain. Those species included southern elephant seals, king penguins, gentoo penguins, Antarctic fur seals and South Georgia diving petrels.

According to the report, approximately 13,359 seal pups from a population of 17,364 on Heard Island died, representing more than 75 percent of the group. Researchers noted that the actual mortality rate could be even higher because deaths were still occurring when surveys concluded. In one monitored area, nearly 97 percent of seal pups were reported dead.
The study also found increased deaths among king and gentoo penguins, although the impact was significantly lower than that seen in seal populations. Researchers stated that no unusual mortality was detected among albatrosses or certain endemic bird species found on the islands.
The findings suggest that bird flu likely reached the islands through migratory birds arriving from the French-owned Crozet Islands, located about 1,800 kilometres away. Australian authorities have described the losses as concerning and confirmed that monitoring efforts will continue as scientists assess the potential risk of the virus reaching mainland Australia.

