Australia's koalas: Freeze sperm to save species, say researchers

Researchers in Australia say freezing koala sperm could help protect the endangered marsupials from extinction.

Scientists at the University of Newcastle in New South Wales have suggested setting up a biolab of collected sperm.

This could then be used as part of a breeding programme to future-proof the species and improve its genetic diversity, they say.

Bushfires in recent years have killed tens of thousands of koalas.

Conservation scientist Dr Ryan Witt said the proposals were a cost-effective way to prevent inbreeding, and therefore help preserve the genetic diversity of koalas beyond small colonies of captive animals:

"Currently... we have no insurance policy against natural disasters like the 2019-2020 bushfires that threaten to wipe out large numbers of animals at the one time," he said.

"If the koala population dies in these kind of fire events, there is no way to bring them back or preserve their genetics."

Live koala young have been born following assisted reproduction using fresh or chilled sperm, the researchers say.

"By using frozen sperm, we can reintroduce genetic variation into wild koala populations without having to relocate koalas," said Dr Lachlan Howell, also of the University of Newcastle.

"We've identified 16 wildlife hospitals and zoos across Australia that could act as nodes to collect koala sperm," he added.