The northern quoll (Dasyurus hallucatus), also known as the northern native cat, the North Australian native cat or the satanellus is a carnivorous marsupial native to Australia.
Taxonomy
The northern quoll is a member of the family Dasyuridae, and is often stated to be the most distinctive Australian quoll. There are three other quoll species found in Australia, and another two species found on the island of New Guinea, all of which are currently placed in the genus Dasyurus. The northern quoll was first described in 1842 by naturalist and author John Gould, who gave it the specific epithet hallucatus, indicating that it has a notable first digit. This species has sometimes been placed in a separate genus, Satanellus.
Four distinct morphological forms of the northern quoll were recognised in the 1920s, however more recent population genomic analysis has shown that these forms do not conform to the underlying genetic differentiation shown across the species distribution.Three broad population genomic clusters are present in the species, which broadly correspond to populations in the regions of Queensland, Northern Territory and Western Australia. This population genomic structure conforms to known biogeographic barriers across northern Australia, including the Carpentarian Gap and Ord Arid Region. Finer scale population structure shows differentiation of the Groote Eylandt and Pilbara populations of quolls.
Life history
The northern quoll is the smallest of the four Australian quoll species. Females are smaller than males, with adult females weighing between and adult males . Head and body length ranges from for adult males and for adult females. The tail length ranges between .
Northern quolls feed primarily on invertebrates, but also consume fleshy fruit (particularly figs), and a wide range of vertebrates, including small mammals, birds, lizards, snakes, and frogs. They also scavenge on roadkills, around campsites, and in garbage tins.
A remarkable feature of this species is that the males show complete die-off after mating, leaving the females to raise the young alone. Females have eight teats in a pouch, but apparently give birth to more than eight young which must wriggle their way to the pouch and compete for a teat to survive. In a study in Western Australia's Kimberley region, the testosterone levels of males peaked in July, and females gave birth in July or August.
In the wild, males live for about one year, while the maximum recorded for a wild female was about three years of age. In rocky habitats, the lifespan of both sexes appears to be increased to two or three years, and individuals are larger than those living in savanna habitats, possibly due to better habitat and reduced predation.
A February 2023 study published in Royal Society Open Science found that "reduced resting behaviour among males could explain the post-breeding death as the deterioration in appearance reflects that reported for sleep-deprived rodents."
Range and habitat
The northern quoll occurs from the Pilbara region of Western Australia across the Northern Territory to south east Queensland. Their historical range extended uninterrupted from S.E Queensland to the Kimberley in Western Australia. There are several disjunct populations. This quoll species is most abundant in rocky ranges and open eucalypt forest. Analysis of occurrence records for the species shows that rocky areas are important for the species.
Northern quolls have declined substantially since European colonisation of Australia, with one study in the Northern Territory finding a roughly 60% contraction in their extent of occurrence. Of the nine species analysed, this decline was only exceeded by that of the brush-tailed rabbit-rat, the sole remaining species in the genus Conilurus. In the Northern Territory, northern quolls appear to be declining towards geographic areas of higher vegetation complexity, lower elevation, and milder temperatures, suggesting that, in these areas, threats may be mediated or better tolerated.
Conservation status
The northern quoll is currently classified as Endangered by the IUCN.
The species is now absent from many parts of its former range, particularly the savanna country. In 2005 it was listed as Endangered under Australian Commonwealth legislation (EPBC Act). Threats are predation by feral cats, dingoes and foxes, particularly after fire or grazing has removed protective ground cover. Destruction, degradation, and fragmentation of the quoll's habitat due to land clearing, grazing, pasture improvement, and mining are also significant. Quolls are also susceptible to being run over on roads.