Biodiversity publications archive

Refugia for biological diversity in arid and semi-arid Australia

Biodiversity Series, Paper No. 4
S.R. Morton, J. Short and R.D. Barker, with an Appendix by G.F. Griffin and G. Pearce
Biodiversity Unit
Department of the Environment, Sport and Territories, 1995

5. Foci of biological diversity in South Australia (continued)

5.4. Gawler

Area

60,308 km².

Primary land-use

Grazing for sheep.

National Parks and Nature Reserves

Lake Gairdner National Park, Lake Gilles Conservation Park (part).

Management problems

Goats, foxes, cats and house mice are common in the Gawler Ranges (Robinson et al. 1988). Grazing by sheep and rabbits threatens to prevent regeneration of long-lived perennial plants (Lange and Purdie 1976; Lange and Willcocks 1980; Woodell 1990). Birds of the chenopod shrublands appear to be particularly at risk of decline (Reid and Fleming 1992).

ANZECC-listed species

Mammals: Sandhill dunnarts Sminthopsis psammophila (V) were discovered in 1969 but have not been seen since (Aitken 1971b in Robinson et al. 1988).

Birds: Malleefowl Leipoa ocellata (E) were recorded in the Gawler Ranges survey (Robinson et al. 1988). The Region is also the site of large number of historical records of night parrots Geopsittacus occidentalis (E).

Plants: Brachycome muelleri (E) was listed by Leigh et al. (1984, pp. 156-7).

Species that are regionally endemic

The gecko Nephrurus deleani is restricted, by apparently unsuitable surrounding habitat, to a very small area in the vicinity of Pernatty Lagoon, between Island Lagoon and Lake Torrens (Cogger et al. 1993, pp. 38-40). It is vulnerable to grazing by rabbits, overgrazing by sheep and cattle, soil compaction and erosion, and to trampling of burrows.

Robinson et al. (1988) listed three plant species endemic to the Gawler Ranges: crimson mallee Eucalyptus lansdowneana ssp. lansdowneana, Grevillea parallelinervis, and the Gawler Range greenhood Pterostylis ovata.

Relict populations

The Gawler ranges subspecies of the thick-billed grasswren Amytornis textilis myall ("locally conspicuous") was recorded in the Gawler Ranges survey (Robinson et al. 1988; see also Garnett 1992, pp. 126-7).

Other significant populations

There are four populations of yellow-footed rock wallabies at the western limit of this species in Australia, and hairy-nosed wombats Lasiorhinus latifrons are abundant in the western half of the Gawler Ranges (Robinson et al. 1988). Birds regarded as of conservation significance are the slender-billed thornbill Acanthiza iredalei, the calamanthus Sericornis campestris and the redthroat Sericornis brunneus, all having declined substantially over this century. Other rare species are the scarlet-chested parrot Neophema splendida, white-browed treecreepers Climacteris affinis and the chestnut quail-thrush Cinclosoma castanotum, which have been recorded only once or not at all.

Robinson et al. (1988) listed five plant species of the Region of significance because they are endemic to South Australia: Acacia tarculensis, Anthocercis anisantha collina, Grevillea aspera, Melaleuca oxyphylla, and Prostanthera florifera. According to Robinson et al. (1988, p. 176), the Gawler Ranges are significant "as a transitional area between the flora and fauna of Eyre Peninsula and the more arid northern areas of the State".

Wetland sites

Morelli and Drewien (1993) listed Lakes Gairdner, Harris, Everard and Acraman, to the south of Kingoonya, as part of a complex of saline lakes including Lakes Frome (section 5.3) and Torrens (section 5.6). Little is known of the biology of the Lakes.

Refugia

Lake Gairdner (see section 11.6) and the Gawler Ranges (11.13) are listed as refugia.