Flying-fox heat stress targeted in world first

The NSW Government’s Saving our Species (SoS) program is pioneering a research partnership to test if water sprinklers can reduce the effects of heat stress on flying-foxes.

Grey-headed flying foxes (Pteropus poliocephalus) in trees

“During the 2019–20 summer over 72,000 grey-headed flying-foxes are estimated to have died in extreme heat events and sadly this is part of an escalating trend for this threatened species,” said Manager Threatened Species Conservation Linda Bell. 

“Flying-foxes feed on nectar and pollen and travel vast distances and are also able to disperse larger seeds. This makes them vital to the health and regeneration of our native forests, especially the hardwood forests our timber industry depends on. 

“This ground-breaking research project will determine whether sprinklers can reduce temperature-related deaths in flying-fox camps and, if so, how they can be configured to provide the best possible result for this threatened species,” Ms Bell said. 

Providing funding of over $128,000, SoS has partnered with World Animal Protection, Campbelltown City Council and Western Sydney University (WSU) to deliver the project.  

Western Sydney University’s Lab of Animal Ecology helped design a scientific experiment investigating the efficacy of using sprinklers.  

Associate Professor Justin Welbergen said his team has been able to gather continuous temperature and humidity data across the camp at different heights across the canopy, thermal data from a drone at regular intervals (before and after spraying from the sprinkler), and also behavioural data. 

“These data allow us to determine the responses of flying foxes to different temperatures and humidity regimes, and the effects the sprinklers have on them," Prof. Welbergen said. 

The council agreed to provide access to the site for the experiment, as well as purchase, installation and ongoing maintenance of the sprinkler water tank.  

“We’re passionate about ensuring the conservation and protection of all wildlife in Campbelltown, including the threatened grey-headed flying-fox which is such an important part of our local ecosystem,” said Mayor George Brticevic. 

“Working collaboratively with experts, government agencies, wildlife care groups and the community offers the best opportunity to achieve this.”   

"Flying-foxes are critical to our unique Australian environment, but the devastating bushfires left them even more vulnerable and we can't let them face this crisis alone,” said World Animal Protection ANZ Executive Director Simone Clarke. 

“That's why we helped fund this vital project, to protect them now and in the future.” 

The project has already commenced and is expected to continue for the duration of this and the forthcoming summer in 2021–22. For more information on flying-fox heat stress go to: Heat stress in flying-fox camps.