Australia on Friday said it will temporarily withdraw researchers from a sub-Antarctic island because of the threat posed by H5 avian influenza, or bird flu, according to a government department.

The Australian Antarctic Division made the "difficult decision" to withdraw staff from the Macquarie Island research station due to psychosocial risks posed by a potential outbreak, the Department of Climate Change, Energy, the Environment and Water said.

The department said 24 expeditioners currently live and work at the research station, established in 1948 on the Southern Ocean island about 1,500 kilometers (932 miles) southeast of Tasmania.

While H5 bird flu has not been detected on Macquarie Island, the island is home to large elephant seal populations close to station buildings, the department said.

Expert assessments predict a high likelihood of a significant mortality event during the upcoming breeding season, it added.

"Elephant seals have proved particularly susceptible to H5 bird flu, with pup mortality rates of more than 90% discovered in some colonies in the sub-Antarctic external territory of Heard Island and McDonald Islands," the department said.

Separately, a dead dolphin found at Goolwa on South Australia's Fleurieu Peninsula tested positive for H5N1 bird flu, ABC News reported.

"We know that dolphins are highly susceptible, which means they are at risk," said South Australia's chief veterinary officer Skye Fruean.

Australia has recorded 354 positive bird flu events in wildlife, including 203 in South Australia, according to official government figures.