Australia — EIGHTEEN years after huge bushfires destroyed much of the Royal National Park, the area’s biggest native mammal has finally returned.
Greater glider possums – tree-dwelling marsupials that grow to nearly a metre – had been missing from the ecosystem since 1994, when fire turned the eucalyptus canopy into a desert of charred tree trunks. But that changed last month when a birdwatcher glimpsed a large, furry shape sailing between trees at dusk.
The news rippled through the ranks of parks and wildlife officers and a spotlighting expedition was mounted.
Before long, there were two more confirmed sightings.
”We’re very excited about this find,” said Debbie Andrew, a biologist with the NSW Office of Environment and Heritage.
Fauna surveys in 1996, 1997 and 2010 found no trace of the marsupial. It is not clear if the glider is a descendant of survivors that endured lean times in the park, or if it migrated along a treetop corridor from the Illawarra.
The nocturnal animal is particularly vulnerable to large fires such as the 1994 bushfires, which claimed four lives and destroyed 101 homes in southern Sydney.
”Greater gliders never come to ground and need a continuous forest canopy to move about,” Ms Andrew said. “That’s why it’s important we continue to protect the moist forest wildlife corridors between Royal National Park and the Illawarra escarpment.”
The gliders spend their lives nibbling eucalyptus buds at the top of big gum trees and each adult has a dozen or more nests in separate hollowed trees, lined with strips of bark.
They can glide up to 50 metres between trees but, in places, the fires left areas of skeletal trees many kilometres wide, forming barriers that would have trapped and starved survivors.
Tanya Leary, a biodiversity officer with the National Parks and Wildlife Service, said most native bushland fauna was accustomed to bushfires but the 1994 fires were big enough to disrupt the entire ecosystem.
”In the case of the greater glider, it would live in habitat that was frequently burned but usually the big, older trees it needs would have survived,” Dr Leary said.
More surveys are being organised to see how many of the gliders have returned to the park.