First H5 bird flu death recorded in endangered Australian sea lion

South Australian officials confirmed that a dead Australian sea lion found on Kangaroo Island on Tuesday represents the first recorded fatality of the species from the H5 strain of avian influenza. The discovery marks the inaugural case of H5 bird flu affecting this endangered marine mammal, prompting heightened surveillance across the region’s coastal habitats.

Authorities estimate the total Australian sea‑lion population at fewer than 12,000 individuals, with some recent surveys suggesting numbers may be under 10,000. The majority of the colony resides in South Australia, while a smaller segment inhabits Western Australia. The Kangaroo Island incident has triggered coordinated response efforts among wildlife veterinarians, biosecurity agencies and conservation groups to contain the virus and protect the remaining sea‑lion populations.