Swarms of moths in Australia lift hopes of recovery for endangered species

Swarms of moths blanketing homes in Australia's southeast in recent days signalled the endangered species is recovering, authorities said on Saturday.

Bogong moths, with a wingspan of up to 5 cm have experienced years of steep population decline, decreasing the visibility of their southern spring migration to caves in the Australian Alps in a journey that can be up to 3,000 km.

But the moths have had a comeback this year, with reports that the insects have invaded backyards and homes along Australia's east coast, including in New South Wales state capital, Sydney.

"It’s really exciting to see this recovering population coming our way," Steve Whan, who represents the alpine area of Monaro in the New South Wales parliament, said in a statement. "The Bogongs are terrific for our ecosystem, supporting our treasured native wildlife like the pygmy-possum and pollinating our eucalyptus trees."

In neighbouring Victoria state, Chief Biodiversity Officer James Todd said it was exciting to see the moths returning in large numbers this year. "The jump in numbers is a positive sign for biodiversity," Todd said in a statement.

The numbers of the moths, which are harmless to humans and legally protected, have fallen due to drought, agricultural intensification and habitat loss, authorities say.

One theory for the rebound is more rainfall in northern New South Wales producing extra food for the insects' larvae, the Australian Broadcasting Corp reported.