Two subspecies have been described: Dasyurus g. geoffroii from central Australia and D. g. fortis from south-western Australia. It seems unlikely that there are two subspecies of D. geoffroii, as minor differences between animals from south-western Australia and those from central and eastern Australia are likely to have been clinal and we do not consider D. g. fortis to be valid. Mitochondrial control region DNA evidence indicates that D. geoffroii is very closely related to the Bronze Quoll D. spartacus of southern New Guinea (Firestone 2000; Woolley et al. 2015). This supports the suggestion that there are no valid subspecies within Dasyurus geoffroii and that D. spartacus may be conspecific with D. geoffroii; however, that taxonomic treatment is not generally recognised, and this account considers D. geoffroii to be endemic to Australia, and does not include D, spartacus.

It is challenging to assess the conservation status of the Chuditch because population size is poorly resolved, population trends vary across sites with increases due to translocations and more intensive control of predators at some sites, but probable decreases at other sites. The Chuditch population size is estimated as less than 10,000 mature individuals and is either stable or declining slightly with numbers varying depending on climate. Over the next 10 years, declining rainfall in the south-west of Western Australia caused by climate change is projected to cause a slow continuing decline in population size across the majority of range occupied by this species due to declining prey availability, however at least some translocated subpopulations are likely to be stable or increasing. Increasing temperatures may affect subpopulations. The population decline due to such climate changes over the next 10 years may approach 10%. Thus the species is assessed as Near Threatened (approaching C1).

The conservation programs that focus on the species are, primarily, fox control via baiting that is carried out over conservation lands in the south west of Western Australia (WA) by the WA state government. This benefits the Chuditch along with other terrestrial mammals within the prey-size range of the Red Fox Vulpes vulpes. In addition, subpopulations of the Chuditch have been established by translocation in other localities where ongoing management excludes foxes or holds densities of foxes at low levels, while also reducing or excluding feral Cats Felis catus.

The Chuditch was formerly distributed over nearly 70% of the Australian continent, occurring in every mainland State and Territory. It was relatively abundant over this large range at the time of European settlement (Collett 1887, cited in Serena et al. 1991, Whittell 1954, Johnson and Roff 1982, Burbidge et al. 1988). However, a drastic decline and contraction of range has occurred since. Specimens were last collected in New South Wales in 1841, Victoria in 1857 and in Queensland between 1884 and 1907. Chuditch were last reported in the arid zone in the mid-1950s (Finlayson 1961), western desert Aboriginal oral history reported that it survived until about 1950 (Johnson and Roff 1982, Burbidge et al. 1988). In Western Australia, the species was still abundant in the south-west in 1907, but had disappeared from coastal areas north of Geraldton by this time (Shortridge 1909). Chuditch occurred on the Swan Coastal Plain until the 1930s (Serena et al. 1991, Orell and Morris 1994).

Burbidge et al. (2009), using modern, historical and subfossil data, found that the Chuditch occurred in 38 of Australia’s 85 bioregions and that it was extinct in 31 and declined or seriously declined in seven.

The Chuditch became restricted to the south west of Western Australia, particularly the jarrah forest and nearby areas, however, small, isolated subpopulations persist in the Avon wheatbelt, parts of the Great Western Woodlands and mallee (Dunlop and Morris 2012), and in and near the Fitzgerald River National Park and Ravensthorpe Range (Sanders et al. 2012). There have been recent records on the Swan Coastal Plan near Baldivis and Yalgorup National Park. It was successfully reintroduced to Julimar Conservation Park in 1992, Lake Magenta Nature Reserve in 1996, Kalbarri National Park in 2000 (Johnson and Orell 2006), and Mt Lindesay National Park, with 63 individuals released there between March 1999 and January 2000. There have been unsuccessful translocations to Cape Arid National Park on the south coast of Western Australia and to François Peron National Park, Shark Bay.

Chuditch were reintroduced to South Australia at Ikara-Flinders Ranges National Park in 2014 and Vulkathunha-Gammon Ranges National Park in 2022. By 2024, Chuditch had been reintroduced to three introduced predator-free fenced mainland islands (exclosures) (Arid Recovery in South Australia, Mt Gibson Sanctuary in Western Australia in 2023-24 and Wild Deserts in New South Wales in 2023), with more fenced sites proposed for reintroduction.

There is a proposal to reintroduce Chuditch to Dirk Hartog Island, Shark Bay (Algar et al. 2020).

A large Dasyurus reported by local Aboriginal people in the north Kimberley (Manglamarra et al. 1991, Karadada et al. 2011) known to Wunambal speakers as Daada, may be this species.

At European settlement, the Chuditch was relatively abundant across its extensive range (Collett 1887, cited in Serena et al. 1991; Whittell 1954; Johnson and Roff 1982; Burbidge et al.1988), but declined rapidly from the early nineteenth century.

In the 1980s, the Chuditch population was estimated to be <6,000 (Serena et al. 1991), including an estimated c. 2,500-4,400 in the jarrah forest (based on trapping records from 1974-1988). However, numbers are now higher due to fox control and translocations, but in 2008 may still have been <10,000 (Morris et al. 2008). Groom and Morris (2009) estimated that there were 12,500 Chuditch in the jarrah forest, and 2,000 Chuditch in the wheatbelt and Goldfields.However, due to the 2023-24 drought in the south-west of Western Australia, numbers are now lower.Isolated subpopulations may be small, e.g. <100 at Julimar (Morris et al. 2008).

At Forrestiana (80 km east of Hyden) with a mean annual rainfall of 340 mm, population density was estimated at 0.039 individuals km^-2. This was almost three times lower than the lowest density estimate in jarrah forest sites, which was from Dwellingup at 0.11 individuals km^-2 and was substantially smaller than the densities estimated at Batalling, at 0.34 km^-2 and Julimar, at 0.68 km^-2 (Rayner et al. 2011).More recent population estimates indicate that densities are highest in Dryandra Woodland National Park, with density estimates of 1.01 individuals km^-2 in 2021. This suggests the population size there could be between 200 and 368 individuals (Drew et al. in draft), assuming equal density across the reserve. The Dryandra subpopulation appears to have benefited greatly from a high level of control of Red Fox and feral Cat Felis catus, which commenced in 2013 within the national park.

Subpopulations in the eastern parts of the wheatbelt, in comparison, are extremely small with Lake Magenta Nature Reserve estimated to have between 7 and 12 individuals, and Dragon Rocks Nature Reserve between 3 and 5. Recent searches in the goldfields (2022 - 2024) did not find any evidence of the species at three reserves west of Kalgoorlie. Several mine sites have, however recorded the species in areas south of Southern Cross. It is estimated that the total population in wheatbelt and goldfields is likely to be fewer than 2,000.

Northern populations such as at Kalbarri appear to have increased from 2018. Despite a translocation to Kalbarri in the early 2000s there was no evidence that the translocated population had survived 8 years after the translocation until camera trapping was used. Recent camera monitoring and targeted cage trap monitoring suggests the species has persisted and may be expanding, with camera records of the species on land to the north of Kalbarri National Park. The subpopulation in Kalbarri National Park is estimated to be between 20 to 40 individuals based on 2019 data. It is likely the population has had higher recruitment recently as a result of increased control of introduced predators within the national park that commenced in 2016. There is no evidence the translocation to François Peron National Park was successful.

Forest populations on average are slightly larger than arid areas with Julimar State Forest estimated to support between 85 and 156 individuals and nearby Avon Valley National Park between 56 and 103, Muja (Batalling) State Forest between 126 and 230 individuals and Tone-Perup between 62 and 114. Populations between Avon Valley and Muja State Forest are extremely sparse and it is estimated that there are fewer than 150 animals in the forest area between these sites. Based on this information it is estimated that there are <5,000 individuals in the forest area of the south west of Western Australia.

Populations on the south coast of Western Australia have not been adequately monitored in recent years. Only one site there has been surveyed for Chuditch in the last 10 years. Monitoring has been conducted at Ravensthorpe and nearby Cocanarup Nature Reserve between 2021 and 2024. There is likely only 7 to 10 resident individuals across these two reserves. Camera monitoring indicates the species is still persisting in Fitzgerald River National Park, albeit at very low densities.

The reintroduced population in Ikara-Flinders Ranges National Park was estimated in 2022 at 359 individuals at a density of 0.07 individuals km^-2 (Schaefer 2024). The fenced reintroduced population at Arid Recovery was estimated at 72 individuals at a density of 1 individual km^-2 in 2022 (Schaefer 2024).

A captive breeding program was established in 2022 at Taronga Conservation Society Australia. The program has been successful in providing animals for release at multiple locations throughout the species former range, including the Vulkathunha-Gammon Ranges National Park and Arid Recovery in South Australia, Mt Gibson in Western Australia and Wild Deserts in NSW (R. Schildkraut, pers. comm, 2024).

Based on these estimates of the size of subpopulations, the total population size is likely to be 5,000-10,000 individuals. Population trend varies amongst sites, with increases due to successes in some translocations and to more intensive predator control, but decreases elsewhere.

Chuditch use a wide variety of habitats including woodland associations, dry sclerophyll forests, beaches and deserts (Burbidge et al. 1988, Serena et al. 1991, Orell and Morris 1994). In the Jarrah forest, Chuditch populations occur in both moist, densely vegetated, steeply sloping forest and drier, open, gently sloping forest. Riparian vegetation appears to support higher densities of Chuditch, possibly because the food supply is better or more reliable, and better cover offered by dense undergrowth may reduce vulnerability to predators. Chuditch also appear to utilise native vegetation along road reserves in the wheatbelt.

Chuditch are nocturnal and generally solitary and can move several kilometres in one night. Serena and Soderquist (1989) estimated the home range in jarrah forest to be 337 ha, with a core area of 90 ha. In more arid habitats larger home ranges are apparently required (Rayner et al. 2011). Within the core area up to 180 den sites, located in hollow logs, tree limbs, rock outcrops and burrows, were utilised. At Ikara home ranges were 245 ha for females and 2,778 ha for males (Moseby et al. 2021).

In the arid zone, Chuditch are known to have denned in termitaria and holes in the ground, including warrens constructed by Boodie Bettongia lesueur (Johnson and Roff 1982, Burbidge et al. 1988). At Kalbarri National Park, Chuditch are at greatest density in the gorges along the Murchison River. Chuditch reintroduced to arid South Australia (<,150 mm average rainfall) were recorded favouring the burrows of bilbies and bettongs in dune habitats and travelling over 3-17 km² per night.

The Chuditch is a generalist predator and an opportunistic hunter, eating small mammals, birds, reptiles, invertebrates and some plant matter. Large invertebrates comprise two-thirds of their diet. They will scavenge carrion and rubbish and prey on chickens (Soderquist and Serena 1994, Stepkovich et al. 2023). At the Arid Recovery translocation site they were recorded killing Boodies Bettongia lesueur, Shark Bay Bandicoots Perameles bougainville and Greater Stick-nest Rats Leporillus conditor (Stepkovich et al. 2023).

The enormous decline in range of the Chuditch since European settlement has been attributed mainly to predation by the European Red Fox. However, in many areas, Chuditch abundance and distribution declined before the arrival of the fox with the pattern of pre-fox decline being consistent across multiple geographic regions, albeit poorly documented. The apparently rapid collapse of populations may have been due to multiple factors such as predation by an expanding feral Cat population, widespread use of strychnine baits to control Dingoes, an undocumented disease, habitat modification by livestock or changed fire regimes. Foxes arrived in the south west of Western Australia in the late 1920s. Before widespread fox control, using dried meat baits with 1080, was implemented in conservation lands in the south west, research demonstrated that baiting did not affect adult Chuditch and that following fox baiting, Chuditch numbers increased. At Batalling (Muja State Forest), Chuditch trap success increased after fox baiting from c. 0.5% in December 1990 to 13% in July 1995 and was then maintained at 4-6% until 1998 (Morris et al. 2003). From 1999 onwards captures declined rapidly and remained below 1% until 2021. Capture rates in 2023 were at 3.8%. Increased predator management within the Muja State Forest site commencing in 2020 has likely supported improved recruitment (M. Drew pers. comm. 2024).

The Chuditch occurs in several national parks, however, much of its range is within State forest, where logging was phased out in January 2024. Thinning and wood collecting continues to occur in state forest with an unknown impact on Chuditch. Morris et al. (2003) studied the impact of timber harvesting at Kingston. Despite confounding data due to increasing numbers of Woylies Bettongia penicillata captured in traps set for Chuditch following fox control, they concluded that logging had little or no effect on Chuditch abundance. The jarrah forest is also subject to rotational prescribed burning and monitoring has shown little impact on Chuditch (Morris et al. 2003), although prescribed burning practices (increased size and frequency) have changed since that study.

Predation by introduced Red Fox and feral Cat are the major threats, and causes of major historical decline. Climate change leading to lower rainfall and higher temperatures are an increasing threat.

Recovery was initially guided by Serena et al. (1991). This was superseded by Orell and Morris (1994), and Dunlop and Morris 2012), with the following recovery actions, most of which have been implemented at least partly:

• Retain and improve habitat critical for survival
• Determine impacts of feral Cats on Chuditch
• Determine the impact of feral cat control methods on Chuditch
• Continue, expand and improve baiting foxes and feral cats
• Determine population abundance and distribution of Chuditch populations
• Establish reference sites for monitoring Chuditch population abundance to evaluate the effectiveness of fox and cat control
• Undertake and monitor translocations to increase the extent of occurrence
• Increase public awareness through community education and enforcement of regulations
• Coordinate recovery implementation

Reference sites were established in 2021 and a captive breeding program was established in 2022 to provide animals for additional translocations. The Chuditch is listed as Vulnerable under Australian and Western Australian environmental legislation.