DENS FOR ENDANGERED NORTHERN QUOLLS
NORTHERN QUOLLS BEING ENTICED BACK TO SAVANAAH LAND WITH ARTIFICIAL DENS
19 SEPTEMBER 2022
Homes are being built for endangered northern quolls in Far North Queensland to entice them back to what was ‘quoll country’ in the days before cane toads.
Northern quolls all but disappeared from savannah land after the arrival of cane toads, but researchers say the small populations that survived and live in patches of rocky country above savannah land, have learned to avoid eating them.
Now dens are being built around the edges of hillsides at Australian Wildlife Conservancy’s Brooklyn Wildlife Reserve, north of the Atherton Tablelands, to help increase quoll numbers and reconnect populations.
Terrain and Gulf Savannah NRMs and Australian Wildlife Conservancy are working together on the project with the help of Ground Creations, who are building the dens, Transport and Main Roads’ Edmonton to Gordonvale project and Mt Carbine’s EQ Resources Ltd, who are each providing some of the resources.
Terrain’s Dr Andrew Dennis said 12 trial dens were being built from pipes, rock and rubble.
“Artificial dens have only been used on rehabilitating mine sites’’ he said. “With their work to guide us, as well as quoll and den research elsewhere, and all the background survey work done by Australian Wildlife Conservancy on where quolls are living in this area, we’ve come up with a new design that should suit the habitat here.
“Unlike on mining land, these dens will be built within undisturbed areas. Their design is based on natural den characteristics, such as depth and temperature and humidity targets.
“The Department of Transport and Main Roads, in collaboration with principal construction contractor HSA Group (John Holland, Seymour White and AECOM) for the Bruce Highway, Cairns Southern Access Corridor, (Stage 3) Edmonton to Gordonvale project is donating some concrete pipes needed for the project and mining company EQ Resources is providing us with rocks and rubble to make this happen.”
The dens are being built just beyond known quoll habitat. If they are successful in drawing quolls back out into flat savannah land, they may be a useful tool to reconnect isolated populations of quolls and improve the endangered species’ genetic health.
Australian Wildlife Conservancy’s Wildlife Ecologist Dr Manuela Fischer said the project is critical in ensuring quolls are able to return into cane toad infested areas and thrive in Far North Queensland.
“Northern quolls are at high risk of genetic isolation and its possible consequences, such as inbreeding depression,” Dr Fischer said. “We are currently collecting genetic samples across different areas on Brooklyn Wildlife Sanctuary to determine if there is any genetic structuring between these areas. We are also collaborating with other researchers to identify genetic structuring at a regional scale within Queensland’s northern quoll populations.”
Dr Dennis said quolls suffered an 80 per cent decline in Queensland as cane toad populations increased. Since then, they seem to have stabilised with populations remaining in pockets where they have learned to avoid toads.
“If this trial works, the lessons learnt could be applied in the Northern Territory and in Western Australia, where there is an ongoing rapid decline’’ he said. “Northern quolls are listed in the top-100 priority threatened species in Australia. Females use seven to 10 hectares as a home range, while males need 70 hectares and more. We want to get them back on the savannah lands, reconnecting isolated populations and keeping genetics healthy while also performing their ecological role there as an apex predators.”
The dens are part of a larger quoll project being delivered by Terrain NRM in partnership with the Western Yalanji traditional owners, Australian Wildlife Conservancy, Gulf Savannah NRM and James Cook University. It is trialling conservation methods and building on previous genetic sampling and fire management work. This project is supported through funding from the Australian Government.
**Photo credits: Wayne Lawler, Australian Wildlife Conservancy, Valeria Silva