Bird Flu H5N1 Strain Kills Over 75% of Baby Elephant Seals on Remote Heard Island
New research indicates the H5N1 strain of avian influenza has caused significant mortality among southern elephant seal pups on Heard Island, one of Australia's remote Antarctic territories. Scientists estimate that approximately 13,000 out of 17,000 baby seals on the island succumbed to the virus since last August, representing over 75% of the local population.
Heard and McDonald Islands, situated roughly 4,000 km south-west of Australia, host over one million breeding seabirds and seals. Data collected between October and January, involving drone surveys and ground visits, confirmed the presence of H5N1 in six species, including southern elephant seals, king and gentoo penguins, Antarctic fur seals, and South Georgia diving petrels.
Dr. Julie McInnes, lead author and wildlife biologist, noted that these observations represent the initial detection of H5 bird flu in an Australian external territory, indicating the virus's eastward progression across the sub-Antarctic. The impact on elephant seals mirrors patterns observed on other sub-Antarctic islands, such as South Georgia.
While Australia remains the sole continent without reported cases of the H5N1 strain, the Environment Minister, Murray Watt, described the seal deaths as “sobering,” emphasising the need for vigilance and preparedness against a potential incursion on the mainland. Researchers suspect the virus was introduced to the islands last August by migratory birds from the French-owned Crozet Islands.
