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

7. Foci of biological diversity in Queensland (continued)

7.4. Mulga Lands

Area

79,874 km².

Primary land-use

Grazing by sheep and cattle.

National Parks and Nature Reserves

Currawinya National Park, Idalia National Park (Queensland), Lake Bindegolly National Park, Nocoleche Nature Reserve, Mariala Scientific Purpose Reserve (New South Wales).

Management problems

Land degradation due to over-grazing (Benson 1991; Pickard 1991; Lunney 1994; Wilcox and Cunningham 1994), clearing of marginal lands (Benson 1991; Cambell 1994), and declining quality of river systems (Pressey and Harris 1988; Dendy and Coombe 1991; Richardson 1994; Sharley and Huggan 1994). Control of vertebrate pests is a critical issue (Freudenberger 1993; Newsome 1994). Invasions of the weed Prosopis spp. are occurring in some places (Cummings et al. 1993).

ANZECC-listed species

Plants: The sedge Eriocaulon carsonii (E) is confined to one mound spring at Peery Lake east of White Cliffs (Bowen and Pressey 1993; Pickard and Norris 1994). Xerothamnella parvifolia and Melaleuca kunzeoides occur in the Region (both V; Purdie 1986). Rhaphidospora bonneyana (V) has also been recorded (Thomas and McDonald 1989). Atriplex infrequens and Maireana cheeli are known from this Region in New South Wales (both V; Bowen and Pressey 1993).

Species that are regionally endemic

Plants listed as endemic by Purdie (1986) are Acacia ammophila, Eremophila linsmithii, Calandrinia sp., Hakea sp., and Dodonaea sp. Neldner (1984) indicated that Acacia ensifolia was endemic to the Region.

Relict populations

Plants listed as possibly relict by Purdie (1986) were Rhaphidospora bonneyana and Acacia spania. Schoenoplectus pungens is recorded only at mound springs near Peery Lake (Bowen and Pressey 1993).

Other significant populations

The yellow-footed rock-wallaby Petrogale xanthopus occurs on rugged sandstone ridges throughout the Grey Range north and west of Adavale, Qld (Gordon et al. 1993). A dasyurid, the kultarr Antechinomys laniger, has declined substantially in the south-east of its range and is now known only from scattered localities (Dickman 1994).

Maher and Braithwaite (1992), Briggs (1994) and Kingsford and Porter (1994) identified the great significance to waterbirds of the Cuttaburra and Paroo systems, and the associated Lakes Wyara and Numalla. Smith et al. (1994) considered many waterbirds to be of conservation concern because of alterations to their habitats.

Plants listed as rare or uncommon by Neldner (1984), Purdie (1986) and Thomas and McDonald (1989) are Ptilotus blakeanus, Actinotus paddisonii, Dipteracanthus corynothecus, Lepidium strongylophyllum, Euphorbia sarcostemmoides, Kennedia procurrens, Eremophila alatisepala, Homocalyx polyandrus, Thryptomene parviflora, T. hexandra and Elacholoma hornii. Purdie (1986) noted that several endemic and significant plants were confined to the Grey and Gowan Ranges. In New South Wales, Bowen and Pressey (1993) noted the following rare or notable plants: Gahnia lanigera, Lomandra patens, Uldinia ceratocarpa, Pluchea baccharoides, Ptychosperma anomalum, Goodenia berardiana, Dentella minutissima, and Zygophyllum humillimum.

Wetlands

The following information is based on Wettin et al. (1993).

Green Creek Swamp: Green Creek is a distributary channel of the Warrego River north-west of Bourke, NSW on the Paroo-Warrego Riverine Plains. The creek is inundated for up to 5 months by run-off from the Warrego River at which time it provides valuable habitat for waterbirds. The vegetation is mainly lignum Muehlenbeckia cunninghamii (Green 1992). This wetland is highly productive when flooded, supporting large numbers and variety of waterbirds. It is also significant for its large population of brolgas Grus rubicundus (Green 1992).

Lake Burkanoko and Lake Nichebulka: Salinas in dunefields east of Wanaaring, NSW on the Paroo-Warrego Riverine Plains. The Lakes experience short-term inundations by local run-off; the water is saline, becoming hypersaline. There is little vegetation other than submerged algae and sea tassel (Goodrick 1984; Maher 1991).

Murphys Lake: A large freshwater pan in dunefields on the Paroo-Warrego Riverine Plains east of Wanaaring, which can retain water for up to 18 months after a flood. The Lake is an important breeding area for waterbirds (Maher 1991).

Paroo Overflow: Distributary channels of the Paroo River, Cuttaburra Creek and Kulkyne Creek and associated wetlands on the Paroo-Warrego Riverine Plains south from Wanaaring to Momba, including Lakes Peri, Gilpoko, Olepoloko, Yantabangee, Mullawoolka and Tongo, but excluding Yantabulla Swamp. The wetlands comprise a reticulate system of broad shallow distributary channels draining into shallow overflow swamps and playa lakes, including Tongo Lake, Mullawoolka Basin, Yantabangee Lake, Poloko Lake, Gilpoko Lake and Peri Lake. Flooding of the area follows general heavy rains in the catchments of the Paroo and Warrego Rivers in south-western Queensland; flooding of the entire system probably occurs in about one in five years although lesser floods are more frequent. Following flooding, water may persist in terminal lakes for periods of up to three years, and thereby provide important drought refuge. In the absence of replenishment flood in this period, the entire system then becomes dry until the next flood. The channels and overflow swamps are vegetated with lignum, which is frequently dense, together with scattered river cooba Acacia stenophylla, coolibah Eucalyptus microtheca, yapunyah E. ochrophloia and black box E. largiflorens. Following flooding, there is an enormous influx of waterbirds to the area and many species breed (Goodrick 1984; Maher and Braithwaite 1992). The system provides habitat for the freckled duck Stictonetta naevosa, and is regarded as being "of critical importance for waterbird conservation" (Maher and Braithwaite 1992, p. 140).

Utah Lake: A salina in dunefields in the Paroo-Warrego Riverine Plains south-east of Wanaaring. The Lake experiences short term inundation by local run-off; the water is saline becoming hypersaline. There is little vegetation other than submerged algae and sea tassel (Goodrick 1984; Maher and Braithwaite 1992).

Willeroo Lake: Paroo-Warrego Riverine Plains east of Wanaaring. A freshwater waterhole fringed by black box and characterised by long term inundation by regional and local run-off (Goodrick 1984). Due to long term inundation, the Lake provides an important drought refuge and important breeding area for waterbirds .

Yantabulla Swamp: Large basin of channels and swamps north-east of Wanaaring. Medium to long term inundation by regional run-off in Cuttaburra Creek. The water is fresh, and lignum is the dominant vegetation (Goodrick 1984; Maher 1991). The more permanent waterholes provide an important drought refuge, important breeding areas for numbers of waterbirds, and important habitat for the freckled duck.

Lake Numalla: A permanent, freshwater to brackish Lake northwest of Hungerford, Qld. The Lake may occasionally connect with the Paroo River. It has a large area of open water habitat, fringing areas of low open samphire Halosarcia spp. shrubland and low open woodland of black box, and claypans with canegrass Eragrostis australasica and lignum. The Lake is an important freshwater body in an arid area, a major habitat for waterbirds (including migratory waders), and an important drought refuge area (Kingsford and Porter 1994). It lies within Currawinya Lakes National Park.

Lake Wyara: A large permanent saline lake adjacent to Lake Numalla; it may have completely internal drainage. There is a large open water habitat, fringing areas of samphire shrubland, and claypans with canegrass and lignum. The Lake is a major habitat for waterbirds, including migratory waders, and an important drought refuge area (Kingsford and Porter 1994). It is also part of Currawinya National Park.

Lakes Bindegolly and Toomaro: The slightly saline Lakes contain permanent water bodies as well as surrounding areas that flood in wet years; they lie east of Thargomindah, Qld. There are open water habitats, seasonally-flooded areas with samphires, black box and coolibah, and ephemerally-flooded areas with claypans supporting lignum, bluebush (Chenopodium auricomum), and canegrass. The dunes surrounding the Lake support the rare plant species Acacia ammophila. The lake is a major breeding habitat and drought refuge for water and other birds typical of southern arid Queensland; more than 42 species of water birds are recorded from the site. The northern half of the site falls within Lake Bindegolly National Park while the southern part is within a pastoral holding.

Refugia

The following refugia are noted: Lakes Numall, Wyara and Bindegolly (see section 13.4), the northern Grey Range (13.7), Peery Springs (14.1), and, as an aggregation, the Paroo wetlands (14.2).