Australia is recognised as the home of the marsupials - that fascinating group of mammals that raise their young in a pouch. But while many of us are familiar with kangaroos, koalas and possums, there are others that are virtually unknown, including one specialised group with over 50 species. This group is the marsupial carnivores.
Even though the majority of the marsupial carnivores are similar in size to many of our native rats and mice, there are larger, possum-sized animals known as quolls.
In Queensland there are two species, the spotted-tailed quoll and the northern quoll. A third species, the western quoll, once lived in Queensland but was last seen here in 1907. Due to habitat clearing and disturbance throughout much of its former range it can now only be found in a small area of Western Australia.
A double tragedy: out of sight and out of mind
The western quoll faced a double tragedy in Queensland. It not only went extinct in this state but it was so little-known that its disappearance was all but unnoticed.
This same double tragedy could face the remaining two quoll species if action is not taken to conserve them and make Queenslanders aware that these marsupial carnivores are part of this state's wildlife. If nothing is done, future generations will only have the poorer experience of being able to look at old photographs of these animals, knowing that they will never be seen again in the wild.
Common name: spotted-tailed quoll
Scientific name: There are two subspecies of spotted-tailed quoll:
Spotted-tailed quoll (northern subspecies), Dasyurus maculatus gracilis
Spotted-tailed quoll (southern subspecies), Dasyurus maculatus maculatus. (Dasy = hairy; urus = tail; maculatus = spotted; gracilis = gracile or slender).
The spotted-tailed quoll (northern subspecies) is listed as Endangered in Queensland (Nature Conservation Act 1992) and nationally (Environment Protection and Biodiversity Conservation Act 1999). It is ranked as a critical priority under the Department of Environment and Heritage Protection (EHP) Back on Track species prioritisation framework.
The spotted-tailed quoll (southern subspecies) is listed as Vulnerable in Queensland (Nature Conservation Act 1992) and is Endangered nationally (Environment Protection and Biodiversity Conservation Act 1999). It is ranked as a high priority under the Department of Environment and Heritage Protection (EHP) Back on Track species prioritisation framework.
Male spotted-tailed quolls have a head-body length of 380-759 mm, a tail length of 370-550 mm and weigh up to 7 kg. Females are smaller in size, with a head-body length of 350-450 mm, a tail length of 340-420 mm and weigh up to 4 kg.
The spotted-tailed quoll ranges in colour from rich red-brown to dark brown with white spots of varying size scattered over both the body and tail. It is distinguished from other quoll species by the spots running along the length of its tail. The fur on the stomach is cream or white.
The head of the spotted-tailed quoll has a distinctive pink-red nose and short, rounded ears that just extend above the outline of the head. In size it is similar to a cat but with a more elongated body and shorter legs. When moving quickly it bounds and it is also an agile climber.
Habitat and distribution
The spotted-tailed quoll (northern subspecies) inhabits coastal ranges (usually 600m or more above sea level) between Townsville and Cooktown. There have also been unconfirmed sightings to the west of Townsville and as far south as the Mackay-Whitsunday area.
The spotted-tailed quoll (southern subspecies) occurs in coastal areas and adjacent ranges throughout south-eastern Australia from southern Queensland to South Australia and Tasmania.
The southern subspecies has been recorded from five broad geographic areas in southern Queensland. Four of these areas are centred on the coastal ranges and the Great Dividing Range from the Queensland-New South Wales border, north to the Gladstone area in central Queensland. The fifth area is centred in the Dalby region, although there are few records and the species is poorly known in this geographic region.
A study of spotted-tailed quoll populations in southern Queensland and far northern New South Wales between 2002 and 2006 found two substantial quoll populations in Queensland: at Girraween National Park and Cullendore (comprised of private properties) (Meyer-Gleaves 2008). The spotted-tailed quoll population at Cullendore has been considered the most abundant known population of the species in Queensland.
The spotted-tailed quoll generally occurs in densely vegetated areas ranging from rainforest and vine-forest through to dry and wet eucalypt forest, woodland and coastal heathland (Watt 1993; Edgar & Belcher 2002). Transient males are sometimes seen in more open areas, including land cleared for pasture.
Spotted-tailed quolls use gullies, drainage lines, escarpments and ridges for foraging and movement within their various habitat types. Rocky outcrops can be important as they contain caves and crevices that are used as den sites
Life history and behaviour
Spotted-tailed quolls are usually nocturnal and solitary. They are territorial and have overlapping home ranges. The home ranges of individuals vary from 100-200 ha for the northern subspecies and up to 580 ha for the southern subspecies. Communal latrine sites can be found where these home ranges overlap and may help an animal advertise its territory or readiness to mate.
Like the Tasmanian devil, the spotted-tailed quoll opens its jaws widely when threatened and gives a piercing scream. Quolls will also be vocal when encountering a potential mate or another quoll in its territory.
Spotted-tailed quolls make dens in tree hollows, logs, rock crevasses and even among building materials. Maternal dens (where young are raised) often have long entrances.
Breeding has been recorded between June and September in the northern subspecies and between April and August in the southern subspecies. Females give birth after a gestation period of twenty-one days and there are usually five young in a litter. The young become independent after 18 weeks and are sexually mature at 12 months of age. Females only produce young in their first two breeding seasons, producing a single litter per year. The northern subspecies is known to have a lifespan of three years.
Spotted-tailed quolls eat a range of animals either as prey or carrion including insects, reptiles, birds and mammals up to the size of a small wallaby. They are also attracted to areas of human habitation in search of food scraps and, in particular, poultry.
The quoll as a chicken killer
When spotted-tailed quolls and backyard chicken runs were more common, the quoll had a reputation as a poultry killer. Often the only time anyone saw a spotted-tailed quoll was when it was discovered in a chicken run - or was shown (dead) in a photograph usually captioned something like "tiger cat - killed 37 chickens".
One of the mysteries surrounding these raids on chicken runs related to how the quoll would often kill many more chickens than it could possibly eat. Why would a quoll do this? One argument is that the quoll as a predator is simply behaving naturally and is responding to the presence of a prey animal that cannot escape. Also, the prey animal may lack the instinctive reaction to escape, making it little more than a "sitting duck" triggering the predator to go on catching and killing prey. The result is that instead of the quoll catching, killing and eating a single chicken (while any others escape), it goes on catching and killing as long as there are chickens present to trigger that behaviour. This situation has also been observed where other wild predators encounter domesticated prey.
The killing of poultry by quolls is not a serious issue in Queensland but may be a problem in isolated areas. The Tree Kangaroo and Mammal Group recommends that the netting on any fence surrounding a poultry yard should be buried at least 15 cm under the ground so that quolls can't dig underneath. If it is a moveable chicken pen, it can have an outwardly-directed skirt of small gauge mesh around it to keep quolls out. There shouldn't be any gaps in the netting used on a quoll-proof fence.
The Tasmanian Parks and Wildlife Service has also developed guidelines for how to protect poultry from spotted-tailed quolls.
Clearing for development and agriculture have reduced the area of available habitat and den sites and caused declines in populations and even local extinctions. Clearing has also exposed spotted-tailed quolls to secondary threats including indirect poisoning from 1080 baiting, hunting, vehicle mortality, predation and competition from feral animals, and its eradication as a pest of poultry. Feeding on cane toads has also resulted in the poisoning of animals.
The following threats to the southern subspecies include:
- habitat loss and modification (including timber harvesting operations)
- habitat fragmentation
- indirect poisoning from 1080 baiting for wild dogs
- competition and predation by feral species
- illegal hunting and trapping
- loss of tree hollows as den sites through fire and vegetation clearing
- prescribed burning and conducting high impact land management activities during the breeding season
- poisoning from ingesting cane toads
A "quollseekers" community program is now recording sightings of spotted-tailed quolls as a way of monitoring changes to their populations and overall distribution.
Landholders are encouraged to protect these animals on private land through preserving its habitat, building quoll-proof poultry yards and responsibly managing dogs and cats.
Studies have been conducted by the Queensland Government, in conjunction with the New South Wales Government and research institutions (DPIF 2008), to ensure wild dog baiting programs do not inadvertently poison spotted-tailed quolls. Baits should not be laid within 300 m of forest edges and should be buried more than 10 cm deep to deter quolls from digging them up.
Common name: northern quoll
Scientific name: Dasyurus hallucatus
The northern quoll is listed as Least Concern in Queensland (Nature Conservation Act 1992) and is Endangered nationally (Environment and Biodiversity Conservation Act 1999). It is ranked as a medium priority under the Department of Environment and Heritage Protection (EHP) Back on Track species prioritisation framework.
Male northern quolls have a head-body length of 270-370 mm, a tail length of 220-345 mm and weigh 340-1120 g. Females are smaller in size, with a head-body length of 250-310 mm, a tail length of 200-300 mm and weigh 240-690 g.
The northern quoll is the smallest of the quolls and varies from grey-brown to brown in colour with large white spots on its head, back and occasionally the base of the tail. The tail is sparsely furred, with a dark brown to black tip lacking spots. Its chest and belly are cream or white in colour.
It has a pointed face similar to many of the smaller marsupial carnivores, and large, prominent eyes and ears. It can be distinguished from the other quolls by its small size, unspotted tail and the clearly striated (ridged) pads on its hind feet that assist in climbing.
Habitat and distribution
The northern quoll once occurred continuously across northern Australia, from the Pilbara, Western Australia to the top end of the Northern Territory and through the Gulf Country and Cape York Peninsula to the Main Range area, south-east Queensland.
The present distribution of the northern quoll has contracted throughout its former range and in Queensland it is now fragmented into a number of populations with the highest densities found in Cape York, the Atherton Tablelands and the Mackay-Whitsunday area. Occasionally there are records of northern quolls as far south as Maleny on the Sunshine Coast hinterland.
The northern quoll lives in a range of open woodland and open forest types preferring rocky areas. Northern quolls have also been recorded in vineforest, mangroves, sugarcane farms and urban areas. Their greatest breeding success is known to occur at sites near water
Life history and behaviour
The northern quoll is nocturnal to crepuscular (active at night & twilight) and shelters in tree hollows, timber piles or rock crevices during the day. They are equally at home on the ground or when climbing in trees and are known for their aggressive behaviour when disturbed. They are usually solitary, except when mating or occasionally when foraging.
Northern quolls are opportunistic feeders and their diet mainly consists of insects. They also feed on small mammals and reptiles, and occasionally fruit and nectar.
Northern quolls have only one breeding season per year, which begins as early as May. Females lack a true pouch, but after mating the area develops around their six or eight teats, creating a flap of skin that helps to contain the young. The young are born between June and September after a short gestation period of just less than a month.. There is an average of six or seven young per litter, but as many as 17 have been recorded.
The young attach to the mothers teats and are carried by her for eight to ten weeks. After this time the young detach from the teats and are suckled in a nest until they are five months old. Up to one-third of a litter may die during this period. The surviving young have been observed still suckling from the mother on a stretched teat while clinging to her back.
Adults become sexually mature at 12 months of age. Females may live for two or three years, only producing one or two litters in their lifetime. Males die soon after mating, rarely living for more than a year.
Habitat destruction for agriculture and urban development is the main threat facing the northern quoll. Loss of habitat and food resources due to inappropriate fire regimes is also a threatening process. Fragmentation of its habitat exposes it to a range of other threats ranging from vehicle mortality and predation by introduced predators to poisoning from ingesting cane toads.
Symptoms of death from cane toad toxin can include bright red lips or gums, a red roof of the mouth, bright red nose and nose bleeds, red ears, bleeding from the ears, a red eye, red skin in the pouch area, bright purple teats and faeces around the anus (Oakwood 2003).
The spread of cane toads into the Northern Territory is now resulting in the local extinctions of northern quoll populations. It is likely, given the scientific data becoming available from the Northern Territory, that the northern quoll in Queensland would have suffered a very high level of impact from the invasion of the cane toad over the past two decades and this impact is likely to be ongoing (DSEWPaC 2010).
A national recovery plan for the northern quoll has been developed outlining the management actions necessary for the conservation of the species. There is a need to raise community awareness about northern quolls to ensure that they receive greater protection outside protected areas. The Wildlife Preservation Society of Queensland (WPSQ) have been running Quoll Discovery Days to involve the community in helping quoll species.
Landholders can protect these animals on private land through habitat protection and responsible pet management. Some things that landholders can do to help include:
- build quoll-proof poultry yards to ensure that quolls are no longer a problem to poultry
- maintain bush on your property, leaving hollow logs and other den refuges
- prevent the use of poison baits or use first generation rodent baits such as Racumin which do not kill quolls
- keep your dogs and cats restrained at night when quolls are active to prevent attacks on quolls.
EHP undertakes planned burns in fire adapted communities to maintain the community and prevent the frequency and intensity of wildfires. EHP is undertaking a project with support and assistance from Reef Catchments and WPSQ to determine if quolls can persist in areas with different fire regimes.
As part of this project in 2011, northern quolls have been surveyed at Crediton State Forest before and after a planned burn using remote cameras, radio-tracking and micro-chipping of individual quolls. Quolls were present both before and after the plan burn, indicating a suitable burn regime was implemented.
Three female quolls recorded prior to the burn had pouch young and their offspring were recorded months after the burn. This indicates that they managed to successfully raise young following the burn. Radio-tracking enabled the identification of den types, the distribution of dens in an area and the number of dens used, as well as the area of habitat used by individual quolls. The gathering of this type of information needs to be duplicated at several locations to develop appropriate fire regimes for quolls.
Edgar R and Belcher C. 2002. Spotted-tailed Quoll, in Strahan R (ed) The Mammals of Australia. Reed New Holland, Sydney.
Hill BM and Ward SJ. 2010. National recovery plan for the northern quoll Dasyurus hallucatus. Department of Natural Resources, Environment, The Arts and Sport, Darwin.
Key threatening process: The biological effects, including lethal toxic ingestion, caused by Cane Toads (Bufo marinus). Department of Sustainability, Environment, Water, Population and Communities.
Maxwell S, Burbidge A, and Morris K. 1996. Action Plan for Australian Marsupials and Monotremes. Wildlife Australia, Endangered Species Program Project Number 500.
Meyer-Gleaves S. 2008. Ecology and conservation of the spotted-tailed quoll (Dasyurus maculatus maculatus) in southern Queensland. PhD thesis. School of Environment, Griffith University.
Oakwood M. 2003. Quolls decline with the advance of toads. Savanna Links (newsletter of the Cooperative Research Centre for Tropical Savannas Management) 26, 6, 12.
Quollseekers Network (Information on Wildlife Preservation Society of Queensland's website)