Lake Galilee is a semi-arid salt lake in the locality of Galilee, Barcaldine Region, within the Desert Uplands area of Central West Queensland, Australia. The lake is about 36 kilometres long, up to 12.5 kilometres wide and covers approximately 25,700 hectares.Environmental Protection Agency, QLD
Lake Galilee is registered on the Directory of Important Wetlands in Australia (DIWA) and provides an important refuge and breeding site for waterbirds. It has been identified by BirdLife International as an Important Bird Area (IBA) because it regularly supports over 1% of the world populations of freckled ducks and grey teals. and possibly more than 1% of the world population of other waterbirds and shorebirds.
The weed Parkinsonia is posing as an environmental threat to the lake as are feral animals, grazing impacts and tourism pressures. The group of property owners adjacent to the lake are working with local natural resource management groups (Desert Uplands Committee and Desert Channels Queensland) to manage these threats.
Description Lake Galilee is a semi-arid, saline, playa tectonic, depressional lake at Galilee, about 76 kilometres north-east of Aramac, in Central West Queensland. It is located in a shallow closed basin bordered by the Great Dividing Range to the west and north. The 255,480 hectare catchment is a closed, internally draining basin, which is fed by some 20 seasonal streams. It is in the Desert Uplands bioregion,Desert Uplands bioregion . the Lake Eyre Basin drainage division, being included within the Thomson River catchment of the Cooper Basin.Cooper Creek basin - wetland summary information . Department of Environment and Heritage Protection. Retrieved on 12 November 2012.
The lake covers approximately 25,700 hectares with a perimeter of 236.7 kilometres. It extends 36 km in a northeast-southwest direction, and is up to 12.5 km wide, with a maximum depth of less than two metres. It has a complex shoreline characterised by many small bays. There are three large islands to the south formed by partial infilling by alluvial sands and clays, which have been carried in by numerous streams.
The water is fresh when full but becomes brackish from leached terrestrial salts as it dries. Water varies from fresh and milky coloured when recently inundated and well into the dry season, to hyposaline in the deepest, southern parts of the lake, which take the longest to dry out. The northern half of the lake is more persistently fresh.Desert Uplands Build-up and Development Strategy Committee and Desert Channels Group. Lake Galilee Management Plan 2011-2016. Lake Galilee falls within the 508 to 610 mm isohyets, with the rain predominantly falling in the summer months from December to March. However, in 2010 there was over 1,000 mm in the catchment.
Together with the smaller Lake Buchanan to the north, Lake Galilee represents a rare type of lake in Australia. Both lake basins represent tectonic depressions created by movements deep in the earth's crust; they have relatively small catchments and are bordered by the Great Dividing Range.2010. Lake Galilee – QLD083 . Directory of Important Wetlands in Australia information sheet. Department of Sustainability, Environment, Water, Population and Communities. Commonwealth of Australia. Retrieved on 9 November.
Wind-borne clay, silt and sand have formed accompanying low fringing dunes, known as lunettes, around the lake. Landforms and vegetation may be exposed or covered by water depending on depth of water. Diversity and complexity are likely to be greatest when the lake is below maximum depth but above half-full depth.
Wetland management profile Semi-arid saline lakes occur in internal (closed) drainage basins where the annual average rainfall is less than 500 mm. Water supply is mainly from the creeks of local catchments with infrequent major rain events providing most of the inflows.Environmental Protection Agency Queensland (1999). Semi-permanent saline lakes of south-western Queensland. Reprinted from Jaensch 1999. The status and importance of Queensland’s south-western wetlands. Report by Wetlands International-Oceania to EPA. In-flowing water is invariably fresh, but becomes brackish or saline over time as the lake dries out.Australian Government, Caring for our Country, Business Plan. (2012-2013) Protecting critical aquatic ecosystems, site: Lake Galilee, Lake Eyre drainage division .
Salinity is due to the pre-existence of salts in the soil and weathered bedrock, and salinity levels range from low (hyposaline) to high (hypersaline). Only a few lakes are distinctly saline for most of the wetting and drying cycle and a single lake may exhibit a mix of both fresh and saline water conditions at one time depending on its topography and the location of the tributaries that carry water into the lake.Gardiner, S. (updated 2010) Wetland Management Profile – Arid and semi-arid lakes. Queensland Wetlands Program (Queensland Department of Environment and Resource Management).
The characteristic landform of an almost flat, shallow, terminal lakebed in an arid and semi-arid zone is commonly called a playa. In dry times, playas consist of cracking clay flats that can be crusted and hardened to varying degrees depending on their substrate and position in the landscape, and sometimes might be covered in a thin layer of soluble salt deposits. Some lakebeds are devoid of vegetation, but others support diverse communities of forbs and grasses as they dry out, which make them a valuable potential grazing resource. When they contain water, arid and semi-arid lakes can also support highly productive aquatic plant beds and algal turfs that are an important component of the food chain.
This profile covers the habitat types of a wetland termed semi-arid saline lake, located on cattle grazing properties in the Desert Uplands bioregion of Central West Queensland. It highlights the steps being taken to preserve the biodiversity and natural heritage.
Wetland habitats
This large lake has six major wetland habitats and include:
Dry saline clay flats which are seasonally flooded; Fringing saline flats on the edges of the lake floor covered by low samphire bushes; Sandy beaches around the edge of the lake, supporting a woodland of beefwood, other grevilleas, sally wattle and ironwood (Acacia excelsa);Acacia excelsa Atlas of living Australia. Retrieved 13 March 2013. Red dunes around the southern part of the lake with gidgee woodland; Freshwater swamps behind the dunes, with coolabahs and; Fringing areas of open wattle scrub in the saline flood zone.
Rare and threatened ecosystems Regional ecosystems are assigned a conservation status based on their current extent in a particular bioregion. This status affords the regional ecosystem a level of protection from vegetation clearing. Regional ecosystems are classified as endangered if the area of remnant vegetation for the regional ecosystem is less than 10% of the pre-clearing extent of the regional ecosystem or the area of remnant vegetation for the regional ecosystem is 10% to 30% of the pre-clearing extent of the regional ecosystem and less than 10,000 hectares.
Out of the 52 regional ecosystems represented in the Lake Galilee catchment, the eight (listed below), are considered endangered. Palustrine wetland. Mostly water or bare ground. Scattered forbs and grasses including Sclerolaena spp. may occur during dry periods. Occurs on infrequently flooded alluvial plains or fringing sandy closed depressions. (BVG1M: 34d) (10.3.16d); Ironwood +/- beefwood low open woodland on lake fringing dunes over a calcrete hardpan adjacent to lake (10.3.17a); Gidgee woodlands on lakeside dunes (10.3.19). This ecosystem is an unusual occurrence, having significant geomorphic values indicative of past climates. It is endemic to Lake Galilee. The deep fine sandy topsoils have very low fertility and are extremely susceptible to wind erosion. It is largely cleared for pasture development. Remnants are heavy infested with buffel grass. In December 2006, remnant extent was < 10,000 ha and 10–30% of the pre-clearing area remained, endangered under the VMA (Vegetation Management Act)Vegetation Management Act 1999 . Department of Environment and Resource Management. Retrieved on 15 November 2012. and the Biodivstat;Biodiversity status, http://www.ehp.qld.gov.au/ecosystems/biodiversity/regional-ecosystems/status.html , Qld Department of Environment and Heritage Protection False sandalwood low open woodland on alluvial plains (10.3.25); Brigalow and blackbutt low forests grassy or shrubby woodlands (10.4.3a); Blackbutt open woodland on Cainozoic lake beds (10.4.3b); Blackbutt open woodland on Mesozoic sediments (10.9.3a); Brigalow woodland on Mesozoic sediments (10.9.3b).
The Regional Ecosystem Description Database (REDD) lists the Biodiversity Status and the Vegetation Management Class (VM class) of each regional ecosystem.Regional Ecosystem Description Database, http://www.ehp.qld.gov.au/ecosystems/biodiversity/regional-ecosystems/how_to_download_redd, Qld Dept of Environment and Heritage Protection.
A further 13 regional ecosystems are “Of Concern”Mitchell, C.; Egan S. & Leverington A. (Draft: 2002) Mitchell, C.; Egan, S. and Leverington, A. (Draft: 2002) Biodiversity Audit – Bioregional Case Study, Desert Uplands bioregion. Queensland Queensland Government Environment Protection Agency, Queensland Parks and Wildlife Service and National Land and Water Resources Audit (A program of the National Heritage Trust).
Nationally important wetland Breeding colonies Common name Scientific name Black swan Cygnus atratus Australian pelican Pelicanus conspicillatus Little black cormorant Phalacrocorax sulcirostris Great egret Ardea modesta Straw-necked ibis Threskiornis spinicollis Royal spoonbill Platalea regia Caspian tern Hydroprogne caspia Silver gull Chroicocephalus novaehollandiae Lake Galilee is registered on the Directory of Important Wetlands in Australia (DIWA). The criteria for determining these nationally important wetlands are agreed to by the Australian and New Zealand Environment and Conservation Council (ANZECC) Wetlands Network in 1994.
Lake Galilee fulfilled four of the six criteria for inclusion as follows. It is a good example of a seasonal/intermittent saline lake with seasonal/intermittent freshwater ponds and marshes on inorganic soils in the Desert Uplands Region. It plays an important role in the natural functioning of a major wetland complex. It plays an important role in the natural functioning of a major wetland complex. It is important habitat for animal taxa at a vulnerable stage in their life cycles, or provides a refuge when adverse conditions such as drought prevail. It supports native plants, animals and ecological communities considered endangered or vulnerable at the national level.
Vegetation There are large areas of samphires (Halosarcia spp.) in broad margins across the lake bed and on islands.(2006) Glasswort, Halosarcia sp . Field Guide to Common Saltmarch Plants of Queensland. The State of Queensland. Retrieved on 10 November 2012. Samphires are succulent, perennial erect or spreading shrubs to one metre tall, often growing in waterlogged and saline areas. They belong on the Chenopod family so are related to saltbushes and bluebushes. Stems and branches are green to reddish-purple, and made up of numerous articulated segments. They do not have obvious leaves; flowers are minute and grow in rows at the base of the fruiting segments.SALTdeck series LWW and AWI (2006) Samphire Halosarcia spp. (S9 Shrub) Sustainable grazing on saline land.
Only young plants may be palatable to animals as they accumulate salt over time. They also act as sediment and nutrient traps and stabilise the lake edge. While they are capable of withstanding harsh climatic conditions, they are easily destroyed by physical trampling.