22 June 2020
POST BUSHFIRE SURVEY SHOWS 90% REDUCTION IN WILDLIFE
One of the first wildlife surveys conducted after Australia’s devastating bushfires has found a 90% reduction in ground dwelling species in burnt areas.
Two small mammals and five skinks were the only low mobility, ground-dwellers located after a search of seven sites in northern New South Wales.
However, there were positive signs of forest regeneration indicating that food and shelter is returning.
The World Wide Fund for Nature-Australia funded Eco Logical Australia (ELA) to conduct the surveys in Gibraltar Range National Park (5 sites in March) and Torrington State Conservation Area (2 sites in February).
Ecologists conducted daytime fauna searches and set up sensor cameras. The number of ground dwelling species detected was less than 10% of what would normally be expected.
The main findings were:
- Fires were widespread in and around the sites surveyed and typically burnt away all ground- cover and nearly all of the canopy.
- Fire impacted wet forests as well as rainforest areas, making them a severe fire incident affecting habitats and species that would normally not be affected by fires.
- Only high mobility species were recorded regularly, particularly kangaroos and wallabies.
- There was an absence of low mobility, ground-dwelling species with only a swamp rat, an unidentified mammal (possibly a Spotted-tailed Quoll or Rufous Bettong), and five smaller reptiles recorded (Murrays Skink x 3, Dark Bar-sided skink x 1, Copper-tailed Skink x 1). Birds that typically spend most of the time on the ground (e.g. quail-thrush and scrubwrens) were also not detected. Quantifiably, this was considered likely to be a > 90% reduction over what could have been expected to be seen.
“Normally you would expect smaller reptiles like skinks and dragons to pop up everywhere. Their absence really shows how devastating fires are for smaller species. They are either unable to escape the flames or have no food or shelter if they do survive,” said report lead author Dr Frank Lemckert, Principal Scientific Ecologist, Eco Logical Australia.
“If drought and fire become more frequent under a changing climate then smaller and less mobile species are likely to decline and may become extinct,” he said.
WWF-Australia conservation scientist Dr Stuart Blanch said the survey re-enforces an important message.
“We must protect forests that did not burn, particularly from logging and being bulldozed. It will take a long time for burnt areas to fully recover. Intact bushland has never been more important,” Dr Blanch said.
“These two protected areas should provide cool mountain refuges from the impacts of global heating. Yet both burnt. It’s a wake-up call. Australia should lead the world in an energy transition to renewables,” he said.
Not all trees are recovering. Many smaller eucalypts were dead and Silver Banksia and Black She-oak were not re-sprouting or germinating and seemed to have been killed by fire.
Sensor cameras detected feral pigs in Torrington State Conservation Area. A concern as they will be preying on and competing with native fauna and damaging the landscape.
However, no feral cats or foxes were recorded which is a major positive because there were fears they would be taking a toll on native fauna exposed because of a lack of ground cover.
Some other positives from the survey were:
- Vegetation was starting to regenerate at all sites indicating that food is becoming available for more generalist species and that shelter is returning.
- The NSW critically endangered threatened species Scrub Turpentine was recorded regenerating in a burnt site in Gibraltar Range National Park.
- Four individuals of the NSW vulnerable threatened species Glossy-black Cockatoo were recorded feeding on She-oak cones adjacent to a survey site in Gibraltar Range National Park.
- Frogs were heard calling from within swamp areas, even though these had been subject to intense fires.