Long-term monitoring of threatened quolls in the Pilbara is helping to better understand their ecology and distribution.
Gathering quality data is enabling scientists to also create better tools to inform management decisions.
The Pilbara Northern Quoll Monitoring Project has been run by the Department of Biodiversity, Conservation and Attractions (DBCA) for the past five years.
The project engages with local traditional owner groups, pastoralists, universities and mining companies to achieve broad ecological research on this endangered species.
DBCA Research Scientist Dr Judy Dunlop said since its inception, over 1600 quoll records have been added to the publicly available database, NatureMap.
“This has enabled the development of a species distribution model allowing us to map the likely distribution of quolls throughout the region,” she said.
Once common across the majority of northern Australia, northern quolls (Dasyurus hallucatus), has had its historical range contracted and habitat fragmented since European settlement.
“The primary cause of decline in this species has been death from predation attempts on the toxic introduced cane toad (Rhinella marina),” Judy said.
“This has resulted in the complete collapse of some northern quoll populations in Queensland and the Northern Territory.
While cane toads have not yet reached the Pilbara, they are projected to naturally colonise the Pilbara mainland between 2026-2064.
DBCA Technical Officer Neal Birch said DNA analysis has shown the Pilbara populations to be genetically distinct from other Northern Australian populations.
“As such, they have high conservation priority due to their separation, distinct genetics, occupancy of a unique habitat niche and exposure to different threatening processes to other northern quoll populations across Australia,” he said.
Current threats to quolls in the Pilbara include predation from feral animals (cats and foxes), altered fire regimes and habitat loss due to industrial developments.
Long term monitoring sites have been established at Dolphin Island, Millstrean National Park, Karijini National Park, Yarrie Station, Mallina Station, Mt. Florance Station, Hooley Station, Indee Station, and the Roy Hill Special Rail Lease.
Neal says additionally, surveys have been undertaken at Karlamilyi National Park and Martu Determination Area where they have been able to confirm the existence of a local population of quolls.
“The first evidence of northern quolls in Karlamilyi National Park (KNP) were found by consultants in 2012 with scats found during survey,” Neal said.
“Annual surveys by DBCA have been conducted since 2015 to determine the range, pedigree and possibly the population size of quolls within KNP – DNA analysis has determined they are Pilbara quolls.”
The Martu people talk of quolls being common in the area historically but had not been seen in living memory.
“In 2016 an individual male was caught and was the first living quoll seen in the area by Martu elders in more than 60 years!”
In 2018, remote cameras detected nine separate quoll detections over an area spanning 80km.
In conjunction with mining partners, the project is also field trialing the Felixer feral cat grooming trap, a new mechanism for targeting feral cats and foxes with promising results.
The project’s efforts have led to the confirmation of an eastern range extension of over 200km into KNP, as well as more comprehensive species distribution model helping inform management decisions on the likelihood of discovering quoll presence within a given area of the Pilbara region.