Quoll’s ark

Relocation to a tropical island that’s free of cane toads is helping ensure the future of the northern quoll.

Story by Kerry Sharp

Light aircraft crisscrossing Australia’s vast northern coastline carry some pretty unusual cargo at times, but none more so than the 65 northern quolls flown out of Darwin to an island haven hundreds of kilometres from their traditional foraging grounds. The little mammals with distinctive white spots and razor-sharp teeth were not impressed about being trussed up in calico bags and stacked in wire-mesh cages in the aircraft cabin for a four-hour flight to the Arnhem Land coast, but they were the lucky ones. Left in their mainland natural habitat, this species faced a bleak future on a diet of deadly cane-toad poison.
Wildlife authorities estimate that tens of thousands of northern quolls have already been wiped from the Top End landscape since the reviled Bufo marinus first crossed the Queensland border into the Northern Territory, near Borroloola, more than 10 years ago. The cane toad was imported into Queensland from Hawaii 70 years ago to control beetles that were destroying the sugarcane, but this wasn’t successful. What no one foresaw then was this creature’s incredible capacity to colonise far afield in huge numbers and wreak havoc on our native wildlife.
The northern quoll’s survival rides on how well it can adapt in safe refuges like the islands it now occupies in The English Companys Islands group in the Arafura Sea to the north-east of Arnhem Land. The early results of the Island Ark experiment are reason for great optimism. From the original 65 released in 2003, at least 500 and probably 1000 northern quolls are now foraging their way across the islands. They have proven to be incredibly robust, even emerging unscathed from a wildfire and category-five cyclone that stripped their new forest home bare.