Australia's H5N1 Bird Flu Cases in Migratory Seabirds Grow to Eight as Surveillance Ramps Up

Australia's H5N1 Bird Flu Cases in Migratory Seabirds Grow to Eight as Surveillance Ramps Up

As of July 9, 2026, the highly pathogenic avian influenza (HPAI) H5N1 strain has continued its slow, isolated spread among wild migratory seabirds along the Australian coastline, with the national tally of confirmed cases rising to eight.

Biosecurity officials and wildlife experts are on high alert, though a massive coastal survey has confirmed that the virus has not yet caused widespread mortality or breached commercial poultry operations.

Case Distribution and New Detections

The eight confirmed cases of H5N1 (clade 2.3.4.4b) are distributed across three states, strictly isolated to wild migratory seabirds (such as giant petrels and skuas):

• Western Australia (WA): 5 confirmed cases. Additionally, WA has reported two new suspected H5 cases in dead petrels found in Perth’s metropolitan area (Mullaloo Beach) and north of Geraldton (Horrocks Beach).
• South Australia (SA): 2 confirmed cases. The second SA case was confirmed on July 8, 2026, in a giant petrel collected from Hardwicke Bay on the Yorke Peninsula. SA authorities are currently testing two more suspected cases collected from Port Vincent and Kangaroo Island (Emu Bay).
• New South Wales (NSW): 1 confirmed case (a giant petrel found near Hawks Nest).

Massive Coastal Surveillance Survey

To assess the scale of the threat, South Australian authorities conducted the largest aerial and ground wildlife survey in over four decades. The rapid biosecurity operation covered over 5,000 kilometers of coastline, islands, and reefs using helicopters, fixed-wing planes, drones, and ground crews:

• The survey recorded more than 30,000 seabirds and seals across 600 locations, including 85 remote islands.
• Encouraging Findings: SA Primary Industries Minister Clare Scriven reported: "Encouragingly, over 5000 kilometres of surveillance has shown that we don't have widespread mortalities in either birds or in wildlife. That is encouraging and speaks to the fact that these are still isolated incidents."

Biosecurity Warnings and Poultry Measures

While the virus has not been detected in any commercial poultry flocks or non-migratory native land birds, biosecurity warnings are escalating. Federal and state authorities are advising free-range poultry farmers to prepare to keep their flocks indoors to prevent contact with wild birds¹ as the high-risk migratory season progresses.²