Two new H5 bird flu events involving Australian sea lions have been confirmed at The Pages off Kangaroo Island, as South Australia’s outbreak grows to 318 confirmed events.
The sea lions were detected on North Page Island and South Page Island through proactive aerial wildlife surveillance being carried out along South Australia’s coastline and offshore islands.
The latest detections are significant given The Pages are an important breeding location for the endangered Australian sea lion. A 2026 threatened species action plan identifies the Pages Islands colony as one of South Australia’s three major breeding sites for the species.
The two sea lion events are among four new confirmed H5 bird flu events reported on Monday, September 21st.
A black-faced cormorant has also been confirmed at Lipson Island off the Eyre Peninsula, while a magpie has tested positive on Hindmarsh Island on the Fleurieu Peninsula.
A large number of dead greater crested terns were also spotted on The Pages during surveillance, although authorities have recorded those deaths as a continuation of an existing H5 event rather than a new event.
The latest update extends confirmed H5 detections in Australian sea lions beyond Seal Bay, where an event involving the species was confirmed on September 13. At that point, South Australia had recorded 290 events.
Concern about The Pages predates the latest sea lion results. In August, around 1,000 dead birds were identified during mass mortality events on islands that host the significant sea lion breeding colony, prompting wildlife experts to closely watch for transmission into the marine mammals.
Australian sea lions are found only in Australia and are federally listed as endangered. The species has a particularly slow breeding cycle, with females returning to the colony where they were born to reproduce, making losses at individual breeding sites particularly important for conservation.
South Australia’s confirmed H5 tally stood at 314 on Sunday, September 20th, following a new event involving an Australasian gannet at Victor Harbor. The four events announced Monday lift that figure to 318.
Authorities stress that an “event” does not necessarily represent one individual animal. South Australia adopted the national reporting system in August, under which an event may involve one or multiple infected animals in a particular location.
More than 2,260 H5 tests have now been carried out in South Australia since the start of 2026, while almost 12,000 reports have been made to the Emergency Animal Disease Hotline since June.
There remain no confirmed H5 bird flu detections in South Australian poultry or other livestock, and authorities continue to assess the risk to human health as low.
South Australians are being urged not to touch sick or dead birds or other wildlife. Anyone who encounters affected wildlife should record what they see and report it to the Emergency Animal Disease Hotline on 1800 675 888.
The next H5 bird flu community forum will be held at Willunga on Tuesday, October 6th.
