First endangered Australian sea lion dies from bird flu

South Australia has recorded the first confirmed detection of H5 bird flu in an Australian sea lion.

SA's environment minister Emily Bourke said the sea lion was found at Seal Bay on Kangaroo Island.

About 85 per cent of the country's Australian sea lions are in SA, with the remainder in Western Australia, according to the National Parks and Wildlife Service which estimates the total population to be less than 12,000.

"We know that in South Australia this is the home of the Australian sea lion. Most of the population is here," Ms Bourke said.

Ms Bourke said the sea lion in Seal Bay was recovering from a shark attack when it succumbed to bird flu.

"We found that it was actually not the shark that killed the sea lion, it was the bird flu case," she said, adding that the sea lion may have been more vulnerable to disease due to its existing injuries.

Ms Bourke said South Australia's sea lion population was already experiencing a decline in population of about 2 per cent every year.

She said other parts of the world had seen a "devastating impact" of bird flu on sea lions and seals, citing the example of Heard Island, an external Australian territory in the Southern Ocean, where research estimates more than 13,000 baby seals have succumbed to bird flu — more than three-quarters of the cohort on the island.

Kangaroo Island Mayor Michael Pengilly said the bird flu case was "not unexpected" but was still disappointing, and he hoped numbers would remain at a minimum.

He said Seal Bay was the "most visited place on Kangaroo Island" and a favourite spot with international visitors.

"Everybody wants to go to Seal Bay, it's a fascinating place. It's a colony, one of the last ones in Australia and it's quite a large colony so it's on the favourite list for everybody including locals," he said.

He said tours of Seal Bay were currently being conducted from the boardwalk rather than the beach to help prevent the spread of bird flu.

Ms Bourke said bird flu has now been detected in four different mammal species in South Australia.

Last month, the virus was detected in a long-nosed fur seal in SA's south-east, marking Australia's first positive case in a mammal.

Ms Bourke said the state has since had two more confirmed cases in long-nosed fur seals, as well as a "number" of confirmed cases in little penguins — including one announced today at Victor Harbor.