Crowned gecko (Lucasium stenodactylum) - vulnerable species listing

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the Crowned Gecko, Diplodactylus stenodactylus Boulenger 1896, as a VULNERABLE SPECIES in Schedule 2 of the Act. Listing of vulnerable species is provided for by Part 2 of the Act.

This species is now known as Lucasuim stenodactylum (Boulenger, 1896) [NSW Government Gazette No. 113, 25 November 2011, Pages 6715-6716].

NSW Scientific Committee - final determination

The Scientific Committee has found that:

1. The Crowned Gecko, Diplodactylus stenodactylus, is a brown or reddish brown lizard, typically with a pale vertebral stripe that commences as separate stripes from each eye that converge and fuse at the nape (Cogger 2000). Individuals reach a total length of approximately 90 mm.

2. The Crowned Gecko is widely distributed from the west and north-west coast of Western Australia, through the Northern Territory and across central Australia (Cogger 2000). In NSW, the species is known from four separate locations in the state's far west: 21 records from Sturt National Park; a 1995 record from Mutawintji National Park; a 1991 record from near Lilly Loch, 125km south of Broken Hill; and eight records from 1981 near Thurloo Downs, 145km east of Tibooburra.

3. The habitat preferences of the Crowned Gecko are largely unknown (Sadlier and Pressey 1994). In NSW, the species has been reported from red sand habitats (R. Sadlier pers. comm.) and elsewhere from savannah woodland (Cogger 2000) and stony areas with shrubs (Swan 1990).

4. The Crowned Gecko is potentially threatened by habitat disturbance in unprotected areas. Grazing by introduced herbivores within Crowned Gecko habitat affects the density and structure of spinifex, adjacent shrubs and ground cover. This degrades Crowned Gecko habitat and increases the risk of predation for individuals moving between patches of vegetation. Disturbance through trampling by stock also degrades Crowned Gecko habitat by altering the soil structure and facilitating weed invasion.

5. The diets of Feral Cats, Felis catus, and European Red Foxes,  Vulpes vulpes, include a significant proportion of reptilian prey (Sadlier  et al. 1996). The degree of threat to the Crowned Gecko from predation by these introduced species is unknown; this impact in concert with threats to the habitat of the Crowned Gecko may potentially be significant.

6. The distribution of the Crowned Gecko is severely fragmented such that local populations of the species are vulnerable to extinction via stochastic events. Despite recent records from within National Parks, this may not ensure the Crowned Gecko's long-term survival in NSW.

7. In view of the above the Scientific Committee is of the opinion that Crowned Gecko Diplodactylus stenodactylus Boulenger 1896 is likely to become endangered in New South Wales unless the circumstances and factors threatening its survival or evolutionary development cease to operate.

Associate Professor Paul Adam
Chairperson

Scientific Committee

Proposed Gazettal date: 25/06/04
Exhibition period: 25/06/04 - 06/08/04

References: 

Cogger HG (2000) 'Reptiles and amphibians of Australia.' (Reed Books: Chatswood)

Sadlier RA, Pressey RL (1994) Reptiles and amphibians of particular conservation concern in the Western Division of New South: a preliminary review. Biological Conservation 69, 41-54.

Sadlier RA, Pressey RL, Whish GL (1996) 'Reptiles and amphibians of particular conservation concern in the Western Division of New South Wales: distributions, habitats and conservation status.' NSW National Parks and Wildlife Service, Occasional Paper 21, Hurstville.

Swan G (1990) 'A field guide to the snakes and lizards of New South Wales.' (Three Sisters Productions: Winmalee)