Wires attributes flying fox starvation to habitat loss and dry winter

Grey-headed flying foxes are starving en masse across New South Wales and parts of Victoria, with wildlife rescuers responding to a surge in reports of “exhausted and emaciated” adults and skeletal pups.

Most reports involved grey-headed flying foxes, listed as vulnerable under Australian federal environment laws and which usually feed on the blossoms and nectar of native trees. The bats are now facing food shortages across NSW, from the northern rivers to the south coast, according to the state’s environment department. Rescue organisations in Victoria are also seeing an increase in callouts, particularly in East Gippsland and Castlemaine.

Rachael Smethurst, the bat coordinator at Fawna wildlife rescue on the NSW mid-north coast, said the organisation was receiving 50 to 90 calls each day — more than the total number of bat callouts in the previous nine months.

The bats were starving, she said. “They’re coming into back yards to eat ornamental fruit trees and eating a lot of ripe and unripe cocos palms. They’re crawling around on the ground eating unripe dropped fruit, and quite literally dropping out of trees due to starvation.”

Flying foxes were staying in backyards because they lacked the energy to fly back to camp, Smethurst said. Many were already dead, including pups that had been born prematurely.

Wildlife rescue organisation Wires said the mass starvation event was likely the result of habitat loss and a dry winter, with poor seasonal flowering of eucalypts and other native species.

“Many malnourished and dehydrated female flying foxes are in the final month of their gestational period and are tragically losing their young,” Wires said. “They just haven’t got the nutritional health or strength to produce milk or carry to full term.”

Some animals were displaying unusual behavior as they struggled to find food and water. “They’re eating off the ground, drinking water from the grass after the rain, and hanging too low in trees.”

Dr Vere Nicolson, a wildlife vet with Wires, said caring for premature pups was “labour intensive and not universally successful,” with the response made more challenging by the number of animals involved.

In Victoria, Tamsyn Hogarth, director of the Fly By Night Bat Clinic, said rescuers were seeing many “exhausted and emaciated” bats and starving babies “like little skeletons” that appeared to be coming from NSW.

Bats spending time in people’s backyards during the day was a red flag, she said. “They’re so hungry they’re actually eating during the day, away from the safety of the camp.” Hogarth said dead pups had been found under trees, and incidents with barbed wire, dog attacks and electrocution had also increased.

A NSW environment department spokesperson said the cause of the incident had not been definitively identified. “We don’t know for sure what is causing this particular incident, but food shortages can be aggravated by climatic events such as drought and El Niño conditions,” the spokesperson said.

The state’s health department reminded the public to avoid touching or handling bats after 43 people were assessed having been scratched or bitten in the past two weeks.

Hogarth said residents who saw sick or dead bats should report them to their local wildlife rescue so volunteers could check for pups, rehabilitate animals where possible and ease the suffering of others. Access to veterinarians able to provide euthanasia was challenging, she said, with so many reports coming from regional or rural areas.

Grey-headed flying foxes typically give birth to one young per year, so the loss of so many pups would have a “terrible ripple effect” for the species, Hogarth said. The food shortages followed thousands of heat deaths in flying fox colonies over the summer, and came amid disruptions to Melbourne’s Yarra Bend camp from freeway construction. “They’re copping it everywhere, they can’t catch a break,” Hogarth said.