Authorities in South Australia are investigating what they believe could be the country’s first mass mortality event linked to bird flu, after more than 80 dead and sick greater crested terns were discovered on a small island off the state’s south-east coast.
The birds were found at Baudin Rock, and samples have been sent to a laboratory in Adelaide for testing to confirm whether bird flu is responsible for the deaths. While the terns have not yet been officially classified as suspected or confirmed cases, officials say the pattern strongly resembles outbreaks of bird flu seen overseas.
South Australia’s chief veterinarian, Skye Freuan, said the discovery was not unexpected given how the virus has behaved elsewhere in the world, but that the speed of its spread in local wildlife was concerning. She said it appeared likely to be the first mass mortality event caused by bird flu since the virus was first detected in a dead migratory seabird in Western Australia. According to Dr Freuan, the outbreak now seemed to be escalating rapidly.
Dr Freuan said the virus was moving through resident bird populations such as crested terns and seagulls, rather than only affecting migratory species passing through the region. Once bird flu establishes itself in wild bird colonies, authorities say there is little that can be done to halt its spread, and large numbers of sick or dead animals become increasingly likely.
The suspected event at Baudin Rock comes as national figures on bird flu detections continue to climb. Federal authorities confirmed at the weekend that a silver gull found at Robe, also in South Australia, had tested positive for bird flu, taking the national tally of confirmed and presumed cases to 53. It was described as the first confirmed detection of bird flu in a silver gull anywhere in Australia, a development experts say could widen the virus’s reach considerably.
Public health specialists have warned that gulls range widely across beaches, wetlands, farmland and urban areas, meaning bird flu could now spread into a much broader mix of wildlife, poultry operations and populated environments. Overseas experience with bird flu suggests Australia should brace for further coastal spread, additional mass mortality events among seabird colonies and marine mammals, and a continued rise in detections over coming weeks.
Just days earlier, 19 greater crested terns from multiple sites along South Australia’s south-east coast and Kangaroo Island were confirmed positive for bird flu, marking the first evidence of local transmission of the virus within the state’s tern population. Conservation groups say Australia is still in the early stages of its bird flu outbreak but caution that the trajectory mirrors what has been observed in South America, where early detections were followed by a rapid increase in cases and geographic spread.
Environmental advocates have called for greater funding to monitor and respond to bird flu, warning that vulnerable native bird species and marine mammals are at high risk as the virus becomes established in Australian wildlife for the first time. The Federal Government has committed $113 million to prepare for the arrival of bird flu in the country, with a further $24 million released to states and territories last month to support surveillance and response efforts.
So far, there have been no detections of bird flu in poultry or within Australia’s broader agricultural production system, and health authorities maintain that the risk to human health remains low. Nonetheless, officials are urging members of the public who come across sick or dead birds, particularly in coastal areas of South Australia, to report the sighting rather than approach or handle the animals, as investigations into the suspected mass mortality event continue.
