Survey guidelines for Australia’s threatened non-flying mammals

Chuditch, western quoll

Dasyurus geoffroii

States and territories: Western Australia.

Regions: South-western Western Australia.

Habitat: Jarrah Eucalyptus marginata forest woodland or mallee shrubland (Serena & Soderquist 1995), specifically in moist, densely vegetated, steep-sloping forest and riparian vegetation (Orell & Morris 1994).

Habit: Ground and tree-dwelling, shelters in dens (earth burrows, hollow logs and hollows in termitaria).

Avg. body weight: 1300 g (males) and 900 g (females) (Orell & Morris 1994).

Activity pattern: Nocturnal/partly diurnal.

Diet: Carnivore: insects, other large invertebrates, small mammals, birds and lizards.

Breeding: Seasonally, with mating occurring late April to early July. Litters of between two and six suckle as pouch young for 61 days and then remain as den young until weaning (approx. September to November) (Orell & Morris 1994).

Description

Chuditch are medium-sized carnivorous marsupials distinguished from other species in their range by their brown fur with white spots and brush-like tail. Males are bigger than females and they also have larger home range areas (approximately 15 square kilometres) compared to females (3–4 kilometres squared) (Serena & Soderquist 1989). Females defend their home ranges, while males range over an area utilised by a number of different females.

Chuditch, like other quolls, shelter in dens during the day, and a female may use on average 66 logs and 110 burrows within her home range over the period of a year (Orell & Morris 1994). Logs that are used as dens must be at least 30 centimetres in diameter, and have a hollow diameter of 7–20 centimetres (Orell & Morris 1994). Burrows are constructed beneath habitat features such as stumps, logs, trees or rock outcrops (Orell & Morris 1994).

The species is an opportunistic feeder, foraging nocturnally for food sources located on the ground and in trees. Individuals will sometimes forage during the day during the breeding season, or if climatic conditions prevent nocturnal foraging (Orell & Morris 1994). Food items include insects, small mammals, birds, reptiles, fruit and flowers.

Survey methods

Recent studies conducted by Wayne and colleagues (2008) found bait to be a contributing factor in the trapping of chuditch with a bait consisting of meat meal, sardines, fish oil, chicken oil and rolled oats (‘chuditch bait’) increasing capture rates. The same study also recommends a relative low trap density and the use of free-swinging bait ‘hooks’ made of fencing wire as a way of reducing the problems associated with ants (Wayne et al. 2008). It is important to note that a completely closed loop rather than a hook should be used in order to avoid injury to trapped animals (Wayne et al 2008).

On the basis of previous surveys, the following survey techniques are recommended to detect the presence of the chuditch in areas up to 5 hectares in size:

• 
  daytime searches for potentially suitable habitat resources, such as jarrah Eucalyptus marginata forest woodland or mallee shrub land (Serena & Soderquist 1995), specifically in moist densely vegetated, steep sloping forest and riparian vegetation (Orell & Morris 1994) (see Ecovision Environmental Consultants 1996). Description of the survey technique and recommended effort is outlined in Section 3.1
  
• 
  daytime searches for signs of activity, including tracks, scats and latrines (description of the survey technique and recommended effort is outlined in Section 3.2)
  

• 
  hair sampling device (hair funnels) surveys, following the description of the technique and recommended effort provided in Section 3.3.7, and using a mixture of sardines, tuna oil and flour for bait. The chuditch is included among those known to be distinguishable from hair samples (see Table 2, Section 3.3.7)
  
• 
  baited camera traps using ‘chuditch bait’ are a more cost effective survey method and also allow for concurrent data to be collected (M Schulz pers. obs.; Nelson 2008).
  

Cage trapping surveys are not considered necessary at the first stage of detection surveys as long as hair funnel or camera trap surveys are employed, as these are an appropriate and effective alternative. Should cage trapping surveys be required, it is recommended that they be conducted according to the description and recommended survey effort provided in Section 3.3.10, provided that permission and licensing has been granted from the relevant Western Australian government organisations. Cage trapping should not be conducted during between mid-August to mid-November when females may have large pouch young or den-young.

Surveys conducted between April and July may detect males in areas where they may not usually occur, either as they move in search of females to mate with or move away from other more competitive males. The locations of these records may indicate important supplementary habitats such as corridors within fragmented landscapes.

Similar species in range

There are no species similar in appearance to the chuditch within its known range.

References

Serena, M and Soderquist, T. 1989. Spatial organisation of a riparian population of the carnivorous marsupial Dasyurus geoffroii. Journal of Zoology, London 219: 373-383.

Serena, M. and Soderquist, T. 1995. The Western Quoll Dasyurus geoffroii. In ‘The Mammals of Australia’. (Ed. R. Strahan) pp 62-63. (Reed Books: Sydney, Australia).
Orell, P. and Morris, K. 1994. Chuditch Recovery Plan. Department of Conservation and Land Management, Western Australia.
Wayne, A.F., Rooney, J., Morris, K.D. and Johnson, B. 2008. Improved bait and trapping techniques for Chuditch (Dasyurus geoffroii): overcoming reduced trap availability due to increased densities of other native fauna. Conservation Science Western Australia, 7 (1) 49-56