Second suspected wildlife mortality event raises concerns over the spread of avian influenza
Australia is facing growing concerns over the spread of deadly H5 bird flu after aerial surveillance detected mass bird deaths in a second state.
Environment Minister Murray Watt said Australia has entered “a long and difficult journey” after CSIRO confirmed the country’s first mass mortality event linked to the virus at Baudin Rocks off the coast of South Australia.
Hours later, Victorian authorities reported that aerial observations had identified a cluster of dead and sick greater crested terns in the Glenelg River estuary near Nelson and across Lawrence Rocks in the state’s south-west.
Victoria investigates possible second bird flu mortality event
If samples from the Victorian birds test positive, the state would become the location of Australia’s second confirmed wildlife mortality event caused by H5 bird flu.
“I want to level with people: this is the beginning of what is likely to be a long, difficult journey in terms of the impacts on wildlife,” Watt said.
Authorities said aerial surveillance over Baudin Rocks identified approximately 50 dead birds and 30 sick birds. Samples from five greater crested terns and one silver gull were analyzed by CSIRO’s Centre for Disease Preparedness and confirmed positive for H5 bird flu.
Government warns spread among wild birds is difficult to control
Officials said controlling the spread of the virus among wild bird populations presents significant challenges because migratory and native birds naturally move across large areas.
“The reality is, you can’t stop native and wild birds flying around, and you can’t stop wild animals moving around,” Watt said, adding that authorities are focusing on strengthening the resilience of native bird and mammal populations.
More bird deaths detected across South Australia and Victoria
Victoria’s chief biodiversity officer James Todd said aerial surveillance findings were consistent with the recent situation reported in South Australia.
Chief veterinary officer Dr Graeme Cooke said monitoring near Portland and Nelson showed a clear increase in the number of dead terns along the coastline.
“Last week we talked about individual detections; the first cases of the H5 bird flu in Victoria. We are now seeing a change as the disease spreads out and has further impacts,” Cooke said.
The affected Victorian region contains important breeding areas for Australasian gannets, seal colonies, the Glenelg estuary, and Discovery Bay, an internationally recognized wetland area.
H5 bird flu reaches new locations in South Australia
South Australian authorities have also raised concerns after a confirmed H5 bird flu case was detected in a migratory petrel found in the Coorong, a significant wetland area supporting waterbirds and migratory species.
CSIRO confirmed 18 additional cases in South Australia, including six birds from Baudin Rocks. Other confirmed cases included silver gulls and greater crested terns across several locations, including Glenelg, Troubridge Island, Southend, Monarto, and Pages Islands.
Environment Minister Emily Bourke said the detection in the Coorong was particularly concerning because the area provides habitat for large populations of waterbirds.
“So it’s going from seabirds, but also potentially now into where we know a lot of waterbirds are nesting and using this space as a safe haven,” Bourke said.
