Lake Bathurst (26481)
Australia, Australasia
Site overview
KBA status: confirmed
Global KBA criteria: D1a
Year of last assessment: 2009
National site name: Lake Bathurst
Central coordinates: Latitude: -35.0457, Longitude: 149.7008
System: freshwater, terrestrial
Elevation (m): 675 to 675
Area of KBA (km2): 19.1125
KBA classification: Global
Legacy site: Yes
Site details
Site description: The IBA includes the main body Lake Bathurst and an adjacent separate body of water known as the Morass, located between Canberra and Sydney. Lake Bathurst is a large, shallow permanent lake occurring near Tarago on the Southern Tablelands of New South Wales, at the southernmost extremity of the Nepean-Hawkesbury catchment, approximately 1km east of Mulwaree River. With a maximum depth of 7m, it is relatively shallow and lies in a basin of internal drainage. The location, size, hydrology and biological diversity of Lake Bathurst and nearby Lake George are unique to the Southern Tablelands; the nearest large natural lake is Lake Cowal, 300km to the north-west. Unlike Lake George, Lake Bathurst has sandier sediments, relatively clear water and low salinity. Rushes (Juncus spp.) grow in the boggiest parts of the lake and pasture species and weeds dominate much of the lake margins. Submerged aquatic vegetation includes Ribbonweed (Vallisneria gigantea) in the deeper sections of the lake, and Sea Tassel (Ruppia megacarpa) and Pondweed (Potamogeton sp.) when the lake is inundated. When dry the lake predominantly supports the herb Selliera radicans and Devils Twine (Cassytha sp.) (Stricker & Wall 1994). The lake is an important waterbird habitat through its availability as a refuge when distant wetlands are dry and it provides habitat for significant breeding activity for some species of waterbirds. The lake is about 20 km east of Lake George, a larger wetland which has been inundated too irregularly and has supported significant numbers of waterbirds too infrequently over the past 25 years to qualify as an IBA (e.g. Freckled Duck, Australasian Shoveler and Australasian Bittern numbers have exceeded thresholds in only two seasons over this time span).
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that meets the thresholds for at least one criterion described in the Global Standard for the Identification of KBAs.
Additional biodiversity: Other species which have once met IBA thresholds include Freckled Duck (486 in 1985/86), Black Swan (11,115 in 1995/96), Chestnut Teal (1165 in 1996/97) and Sharp-tailed Sandpiper (4477 in 1995/96). Other species with maximum numbers recorded include Musk Duck (295), Australian Shelduck (1456), Pink-eared Duck (3255), Hardhead (600), Hoary-headed Grebe (3643), Eurasian Coot (15,800), 28 wader species including Red-necked Stint (935), Curlew Sandpiper (450), Black-winged Stilt (859), Banded Lapwing (67) and up to 3500 breeding Silver Gulls. The lake has supported more than 20,000 waterbirds in 10 seasons between 1980-2005. Non-waterbird species recorded in the IBA include the near threatened Flame Robin and Diamond Firetail, both of which are uncommon (Atlas of Australian Birds database).
Other site values: Private - leased Crown Land. Permission should be obtained from land owners.
Habitats
Land use: rangeland/pastureland (100%)
| IUCN Habitat | Coverage % | Habitat detail |
|---|---|---|
| Wetlands(Inland) | 100 |
Threats
Summary of threats to biodiversity at KBA: Regulate water abstraction from the lake and its catchment. Identify local actions e.g. drought tolerant species, improved water use efficiency, to mitigate impacts of drought. Investigate appropriate areas for grazing and sustainable stocking rates to minimise erosion and weed infestation, and fence off sensitive areas.
| Threat level 1 | Threat level 2 | Threat level 3 | Timing |
|---|---|---|---|
| Invasive & other problematic species, genes & diseases | Invasive non-native/alien species/diseases | Named species | Ongoing |
| Climate change & severe weather | Droughts | Ongoing |
Additional information
References: Braithwaite, L.W. (1982) Ecological studies of the Black Swan. IV. The timing and success of breeding on two nearby lakes on the southern tablelands. Australian Wildlife Research 9: 261-275. Canberra Ornithologists Group (1982-2006) Annual Bird Reports. Published in Canberra Bird Notes Volumes 7 (1982) to 31 (2006). Davey, C.C. (1991) A visit to the Silver Gull breeding colony at Lake Bathurst, NSW, September 1990. Canberra Bird Notes 16: 1-3. Stricker, J.S. and Wall, C.A. (1994) Wetlands of the Nepean-Hawkesbury Catchment. Sydney: Sydney Water Corporation. WetlandCare Australia (2008) Draft Lake Bathurst and The Morass Wetland Management Plan. Unpublished report to Hawkesbury-Nepean CMA. '
Contributors: Dr Michael Lenz, Chris Davey and other members of the Canberra Ornithologists Group have contributed data from many years of monitoring birds. Michael Pattison provided draft management plans by WetlandCare.