Mass deaths across two states have marked a major shift in Australia's bird flu outbreak, as authorities seek approval for vaccinations to protect vulnerable animals.
Aerial surveillance detected more than 1000 dead crested terns on remote islands off South Australia, Premier Peter Malinauskas said on Thursday.
On King Island off Tasmania, 28 dead penguins were also discovered, a week after confirmation of the state's first bird flu case.
"The loss of more than 1000 birds is deeply concerning and the state government is treating these events with the utmost seriousness," Mr Malinauskas said on Thursday.
There was also the disconcerting news of a suspected flu death involving a little penguin on Kangaroo Island, he said.
SA authorities were seeking approval for a vaccination program for penguins and potentially other species, including the black-bellied parrot, the premier said.
The vaccinations, which require two separate injections, would initially be focused on captive animals, such as those at Adelaide Zoo and Cleland Wildlife Park, but there was no timeline on its rollout.
The island deaths were detected on Wednesday at North and South Page Islands off Kangaroo Island, and Troubridge Island, off Yorke Peninsula.
SA has 177 confirmed bird flu events, the most of any state.
NSW authorities on Thursday reported two H5 events, involving seven birds.
Six infected greater crested terns and one diseased giant petrel were discovered at Narooma and Merimbula, on the state's south coast.
SA primary industries department biosecurity chief Georgie Cornish said bird flu reporting had moved from individual cases to events to make sure people understood how it was moving across the landscape.
The mass island deaths were in areas where events had already been reported, and there were also seven new events in SA reported on Thursday.
In Tasmania, specialist teams had been sent to King Island after 28 penguins and three crested terns were discovered at the Port of Grassy.
The animals were being tested for H5 bird flu, Tasmanian Premier Jeremy Rockliff posted on social media.
Tasmania has 11 confirmed bird flu cases since the virus was first found in the state on August 13 at Rocky Cape, on the north-west coast.
– AAP