Biodiversity

Species Profile and Threats Database


For information to assist proponents in referral, environmental assessments and compliance issues, refer to the Policy Statements and Guidelines (where available), the Conservation Advice (where available) or the Listing Advice (where available).
 
In addition, proponents and land managers should refer to the Recovery Plan (where available) or the Conservation Advice (where available) for recovery, mitigation and conservation information.

EPBC Act Listing Status Listed as Endangered
Recovery Plan Decision Recovery Plan required, included on the Commenced List (1/11/2009).
 
Adopted/Made Recovery Plans Recovery Plan for the Kangaroo Island Dunnart Sminthopsis aitkeni (South Australia Department of Environment and Natural Resources (SA DENR), 2011e) [Recovery Plan].
 
Other EPBC Act Plans Threat Abatement Plan for predation by feral cats (Department of the Environment, Water, Heritage and the Arts (DEWHA), 2008zzp) [Threat Abatement Plan].
 
Policy Statements and Guidelines Survey guidelines for Australia's threatened mammals. EPBC Act survey guidelines 6.5 (Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC), 2011j) [Admin Guideline].
 
Federal Register of
    Legislative Instruments
Declaration under s178, s181, and s183 of the Environment Protection and Biodiversity Conservation Act 1999 - List of threatened species, List of threatened ecological communities and List of threatening processes (Commonwealth of Australia, 2000) [Legislative Instrument].
 
State Government
    Documents and Websites
SA:Threatened Species - The Kangaroo Island Dunnart - Rare or Elusive? (South Australian Department for Environment and Heritage (SA DEH), 2009g) [Internet].
State Listing Status
SA: Listed as Endangered (National Parks and Wildlife Act 1972 (South Australia): June 2011 list)
Non-statutory Listing Status
IUCN: Listed as Critically Endangered (Global Status: IUCN Red List of Threatened Species: 2013.1 list)
Scientific name Sminthopsis aitkeni [300]
Family Dasyuridae:Polyprotodonta:Mammalia:Chordata:Animalia
Species author Kitchener,Stoddart and Henry,1984
Infraspecies author  
Reference  
Distribution map Species Distribution Map

This is an indicative distribution map of the present distribution of the species based on best available knowledge. See map caveat for more information.

Illustrations Google Images

Scientific name: Sminthopsis aikeni

Common names: Kangaroo Island Dunnart; Sooty Dunnart

Recent synonyms: Sminthopsis murina

The species is conventionally accepted.

The Kangaroo Island Dunnart is a small marsupial with dark, sooty fur above and light grey fur underneath. Adults grow between 80–90 mm long, weighing up to 25 g. This species has a slender, pointed muzzle and a thin tail growing to 10.6 cm long (Strahan 1998). It is distinguished from similar looking species by the dark sooty colour of the dorsal fur by its slender pointed muzzle (Strahan 1998), and is the only dunnart occurring on Kangaroo Island.

Australian distribution

This species is found in the western half of Kangaroo Island, in remnant habitats of eucalypt woodland, primarily on sandy soils, often with a low heath understorey. It was last recorded in 2001, with 22 dunnarts being captured from six locations, including four new locations, adding to the 10 individuals caught since 1969. All recent catches were in protected locations where native vegetation remains intact (Gates 2001b).

Extent of occurrence

The six current sites where the Kangaroo Island Dunnart is known to occur are from the western side of the island. As a very small number of individuals have been recorded between these six locations, the extent of occurrence is extremely difficult to calculate. The clearing of nearly 50% of the island vegetation may correlate with the extent of occurrence and the decrease in the dunnarts (Gates 2001b). Also, the recent fire history in the eastern side of the island may also be a contributing factor (Gates 2001b).

Area of occupancy-western side of Kangaroo Island

The area of occupancy of the Kangaroo Island Dunnart is also difficult to estimate due to limited data, however the discoveries of dunnarts on only the western side of the island suggests that the area of occupancy has contracted in the last decade (Gates 2001b). The Kangaroo Island Dunnarts were originally thought to be found only on the eastern side of the island, perhaps due to the larger human presence, a greater survey effort and disturbance on this side (such as land clearing) which expelled the dunnarts from their habitats, resulting in their discovery in 1969, fleeing from fallen Yaccas (Xanthorrhoea semiplana tateana) (Gates 2001b; Herbert 1996).

Population locations

The most recent research on the Kangaroo Island Dunnart revealed a western distribution of the species, with other sites not being located since 1990 (Gates 2001a). Their current locations are scattered around the Ravine des Casoars Wilderness Protection Area and the Flinders Chase National Park (Gates 2001b). Due to the small size and elusive nature of the dunnarts (Gates 2001b), undiscovered populations are expected to occur throughout Flinders Chase National Park, in areas where native vegetation remains (Gates 2001a).

Fragmented distribution

The Kangaroo Island Dunnart has a naturally limited distribution and fragmented population, at the national scale. The loss of the species on the eastern side of the island suggests that the species is limited into the western side of the island where natural, undisturbed native habitat remains (Gates 2001a).

The most recent survey to date was conducted by Gates (2001b) which captured and recorded 22 Kangaroo Island Dunnarts using a combination of pitfall and Elliott traps across 46 sites. In total, there were 13 700 pitfall trap-nights and 8900 Elliott trap-nights, one of the most extensive studies to date. Previous to this survey, only ten specimens have been recorded since 1969 (Gates 2001b), and some attempts failed to detect any (Maxwell et al. 1996). There have also been a handful of anecdotal sightings.

Population totals and trends

The total population size of the Kangaroo Island Dunnart is unknown due to the limited data available (only 32 caught specimens). However a figure of approximately 500 is thought to be the total size (Gates 2001a).

There is a trend of population contraction in terms of the area in which they are found. Habitat loss is thought to be the main reason for this apparent decline in distribution, and it is thought that population trends follow this habitat decline (Yates 2001a, b).

Generation length

It appears that adults live only for one year, or two breeding seasons, as there are two breeding seasons per year. Individuals reach sexual maturity at six months, therefore the generation length is somewhere between six months to a year (Gates 2001b).

Important populations

The six identified populations on the western side of Kangaroo Island are all deemed to be important as their slight separation is thought to aid in the genetic diversity of the species (Gates 2001b).

The entire population of Kangaroo Island Dunnarts identified by the most recent survey (Gates 2001b) was found in the Ravine des Casoars Wilderness Protection Area and the Flinders Chase National Park.

General description

The Kangaroo Island Dunnart has been recorded from sea level to 240 m in Brown Stringybark/ Cup Gum (Eucalyptus baxteri/ E. cosmophylla) low to very low open woodland. One was recorded from Kingscote Mallee (E. rugosa) low open woodland and one from Kangaroo Island Mallee-ash (Eucalyptus remota) low to very low woodland (Herbert 1996). Most records are from areas with sandy soils and low heathy lower stratum vegetation.

Biological habitat

There is little data on the habitat preferences of the dunnarts, indeed it is likely that the Kangaroo Island Dunnart is a habitat generalist, with broad use of native vegetation recorded (Gates 2001b). It is therefore likely that the remaining vegetation on the island could potentially be suitable for the dunnarts habitat or shelter on night foraging movements. The six sites where the dunnarts are recorded to inhabit all occur within the higher rainfall areas of the island. Of these sites, the major vegetation associates are Kangaroo Island Mallee-ash open low mallee, and Brown Stringybark low woodland.

There is thought to be high variation within these associations, including floristics, secondary overstorey species and densities (Gates 2001a). The understorey at these locations is usually sparse and variable, and includes species such as Desert Banksia (Banksia ornata), Silver Banksia (B. marginata), Guinea-flowers (Hibbertia species), Yakkas (Xanthorrhoea semiplana tateana), Beaked Hakea (Hakea rostrata), Rushes (Lepidosperma species), Bearded-heath (Leucopogon concurvus), Kangaroo Island Cone-sticks (Petrophile multisecta) and the Common Fringe-myrtle (Calytrix tetragonal) (Gates 2001a).

Importance of Yakkas

There appears to be a preference for sheltering under Yakkas, including ones that are suffering from Phytophthora dieback; indeed four of the first individuals collected were caught while fleeing from the bases of felled Yakkas (Maxwell et al. 1996). The dunnarts are also thought to spend periods of up to four hours using these Yakkas shelters at night on foraging expeditions (Gates 2001b).

Sexual maturity and mortality

There is very little data on the life history of the Kangaroo Island Dunnart, however the breeding season is estimated around spring and summer. Gestation is approximately 12 days, with young leaving the nest at 21 days old. Young separate from their mothers at 56 days old and reach sexual maturity at six months. It is expected that like other dunnart species, they do not live longer than a year, although it is suggested that females may survive to breed for two years (Gates 2001a). This short longevity correlates with the low number of adult dunnarts captured during the most recent survey (Gates 2001b) in the post-breeding season of late summer and autumn.

Reproduction

Little is known about the reproductive cycle of Kangaroo Island Dunnarts. Females are thought to be polyestrous which is similar to the reproductive cycles of the Common Dunnart (Sminthopsis murina) (Fox & Whitford 1982), therefore mating is thought to occur around twice a year, first in spring and again in summer, with two cohorts of young conceived between mid-September and early October and the second cohort between November and December (Gates 2001b).

Ground-dwelling invertebrates are the primary food source for the Kangaroo Island Dunnart (Gates 2001a), with scat analysis (Gates 2001b) showing spiders (recorded in 59% of scats) and ants (recorded in 56% of scats) as the primary items; with beetles and scorpions also recorded (in 36% of scats) and one record of grasshopper and centipede (Gates 2001a).

As with other dunnarts (Kitchener et al. 1984), the Kangaroo Island Dunnart is nocturnal, moving around mostly at night, with a short period of rest at night (around 2 hours). The same dens are used during both day and night, and a series of shelters are accessed over the home range (Gates 2001b). It seems that the home range size for the dunnarts is between 0.34 ha and 2.32 ha, with males moving around up to 290–380 m, and females moving around up to 170–180 m per night (Gates 2001b).

Isolation and habitat loss

The Kangaroo Island Dunnart is threatened by severe isolation of its population, and the many compounding factors that aid in habitat loss. This habitat may result in a more fragmented distribution. These factors include:

  • an altered fire regime with less frequent, but more intense fires
  • native vegetation clearing
  • on going modification of the remaining habitat as a result of grazing (both native and exotic animals) (Gates 2001a).

Fire presents a serious threat as it can spread into the national park and protection areas, impacting upon the remaining six sites on the island. Although the evidence for each of these factors is only the association with native vegetation (with a decrease in native vegetation thought to signal a decrease in dunnart populations), the precautionary principal is called upon to protect the remaining populations (Gates 2001a).

Catastrophic events

If a catastrophic event should occur on Kangaroo Island, such as a large scale fire or flood, the survival of the Kangaroo Island Dunnart could be highly threatened. It is possible that the genetic transfer that could be occurring between these populations, or indeed the whole population itself, may be lost in one severe catastrophic event.

The threats to the Kangaroo Island Dunnart are being abated using the objectives of the 2002–2005 Recovery Plan. These include six strategic areas, which were carried out by: the Department of Environment and Heritage (DEH) Conservation Programs Unit; Kangaroo Island field staff; contract fire ecologists; contract biologists; landholders and community members; DEH Biological Conservation, Threatened Species Unit, Adelaide; and local Country Fire Service brigades (Gates 2001a). The strategic areas are (Gates 2001a):

Strategic Area 1: Site Protection and Management of Known Populations

To develop and implement management prescriptions to protect and conserve all known sites with populations of Kangaroo Island Dunnarts.

Strategy Area 2: Clarify Distribution and Threatening Processes

2.1 To improve methods of detecting the Kangaroo Island Dunnart.

2.2 To enhance protection of potential dunnart habitat and investigate the impacts of fire on the species by:

  • Reducing the severity and extent of wildfires and associated back-burning operations.
  • Increasing the complexity of the mosaic of successional stages of habitat within Flinders Chase National Park and Ravine des Casoars Wilderness Protection Area.
  • Determining if the post-fire age-class of vegetation influences the distribution and abundance of the dunnarts.

2.3 To continue to clarify the influence of habitat type and patch size on the distribution of the Kangaroo Island Dunnart.

2.4 To investigate the impact of Phytophthora on the abundance and distribution of Yakka, an important habitat plant. An effect on the Yakka may have a potentially negative impact on the Kangaroo Island Dunnart.

2.5 To investigate the potential for predation or spread of toxoplasmosis by feral Cats (Felis catus).

Strategic Area 3: Investigate Ecology and Biology

To gain a better understanding of Kangaroo Island Dunnart ecology and biology and to determine if threats are likely to be caused by habitat limitations or predation by identifying:

  • breeding biology including reproductive output and survival
  • movement patterns, home range size and habitat use
  • areas of high use
  • shelter requirements
  • dispersal ability.

Strategy Area 4: Community Awareness

To continue to raise community awareness and support for the Kangaroo Island Dunnart recovery program through community education and involvement in the program.

Strategic Area 5: Establishment of a Captive Colony

To investigate the possibility of a captive colony of Kangaroo Island Dunnarts.

Strategic Area 6: Recovery Planning

To ensure that the Recovery Plan is implemented as efficiently and effectively as possible.

Management documents for the Kangaroo Island Dunnart include:

  • Recovery plan for the Kangaroo Island Dunnart Sminthopsis aitkeni: 2002-2006 (Gates 2001a).

The following table lists known and perceived threats to this species. Threats are based on the International Union for Conservation of Nature and Natural Resources (IUCN) threat classification version 1.1.

Threat Class Threatening Species References
Agriculture and Aquaculture:Agriculture and Aquaculture:Land clearing, habitat fragmentation and/or habitat degradation Sminthopsis aitkeni in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage, 2006xj) [Internet].
Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or predation Felis catus (Cat, House Cat, Domestic Cat) A taxonomic revision of the Sminthopsis murina complex (Marsupialia: Dasyuridae) in Australia, including descriptions of four new species. Records of the Western Australian Museum. 11:20111-248. (Kitchener, D.J., J. Stoddart & J. Henry, 1984) [Journal].

Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC) (2011j). Survey guidelines for Australia's threatened mammals. EPBC Act survey guidelines 6.5. [Online]. EPBC Act policy statement: Canberra, ACT: DSEWPAC. Available from: http://www.environment.gov.au/epbc/publications/threatened-mammals.html.

Fox, B.J & D. Whitford (1982). Polyoestry in a predictable coastal environment: reproduction, growth and development in Sminthopsis murina (Marsupialia: Dasyuridae). In: Ed. M. Archer, ed. Carnivorous Marsupials. Page(s) 39-48. Sydney: Royal Zoological Society of New South Wales.

Gates, J.A (2001a). Recovery Plan for the Kangaroo Island Dunnart Sminthopsis aitkeni: 2002-2006. Kingscote: Department of Environment and Natural Resources.

Gates, J.A (2001b). The Distribution and ecology of the Kangaroo Island Dunnart Sminthopsis aitkeni: Final Report.

Herbert T. (1996). Distribution, habitat preferences and status of the Kangaroo Island Dunnart (Sminthopsis aitkeni). Nature Conservation Society of South Australia.

International Union for Conservation of Nature (IUCN) (2010). IUCN Red List of Threatened Species. Version 2010.4. [Online]. Available from: http://www.iucnredlist.org.

Kitchener, D.J., J. Stoddart & J. Henry (1984). A taxonomic revision of the Sminthopsis murina complex (Marsupialia: Dasyuridae) in Australia, including descriptions of four new species. Records of the Western Australian Museum. 11:20111-248.

Maxwell, S., A.A. Burbidge & K. Morris (1996). The 1996 Action Plan for Australian Marsupials and Monotremes. [Online]. Wildlife Australia, Environment Australia. Available from: http://www.environment.gov.au/resource/action-plan-australian-marsupials-and-monotremes.

Strahan, R. (Ed.) (1998). The Mammals of Australia, Second Edition, rev. Sydney, NSW: Australian Museum and Reed New Holland.

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This database is designed to provide statutory, biological and ecological information on species and ecological communities, migratory species, marine species, and species and species products subject to international trade and commercial use protected under the Environment Protection and Biodiversity Conservation Act 1999 (the EPBC Act). It has been compiled from a range of sources including listing advice, recovery plans, published literature and individual experts. While reasonable efforts have been made to ensure the accuracy of the information, no guarantee is given, nor responsibility taken, by the Commonwealth for its accuracy, currency or completeness. The Commonwealth does not accept any responsibility for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the information contained in this database. The information contained in this database does not necessarily represent the views of the Commonwealth. This database is not intended to be a complete source of information on the matters it deals with. Individuals and organisations should consider all the available information, including that available from other sources, in deciding whether there is a need to make a referral or apply for a permit or exemption under the EPBC Act.

Citation: Department of the Environment (2014). Sminthopsis aitkeni in Species Profile and Threats Database, Department of the Environment, Canberra. Available from: http://www.environment.gov.au/sprat. Accessed Tue, 23 Sep 2014 18:42:44 +1000.