Current view: Text account
Site description (2008 baseline):
Site location and context
The IBA consists of a chain of brackish, saline and freshwater wetlands extending from near Olivers Lake (approximately 12 km north of Natimuk) south to Ti Tree Lake (approximately 8 km south of Douglas) in western Victoria. The IBA is situated in the semi-arid Wimmera region, which experiences hot and dry summers and mild and wet winters. Waterbird numbers are greatest between July and November of most years, but particularly when there has been good rainfall in the region and when inland Australia is dry. Most of the wetlands captured by the IBA are subject to seasonal or otherwise episodic flooding, but some (e.g. Saint Marys Lake) are permanent and retain water throughout the year. The wetlands collectively receive water from a variety of sources including direct precipitation, groundwater, run-off, drainage lines, local catchments and overflows. Many of the wetlands are fringed by saltmarsh, but other vegetation communities such as sedgeland and Paper Bark forest are also prominent.
At least 81 species of bird have been recorded around the Natimuk-Douglas wetlands (Birds Australia 2002). This figure includes twenty species listed under one or more of the Japan-Australia Migratory Bird Agreement (JAMBA), China-Australia Migratory Bird Agreement (CAMBA) and Bonn Convention (CMS); ten species listed as threatened in Victoria under the Flora and Fauna Guarantee Act 1998; and one species (Red-tailed Black-Cockatoo) listed as nationally threatened under the Environment Protection and Biodiversity Conservation Act 1999 (Birds Australia 2002). Species recorded in moderate but sub-threshold numbers are Musk Duck (maximum 91 birds), Black Swan (maximum 3902 birds), Grey Teal (maximum 10,074 birds), Hoary-headed Grebe (maximum 3334 birds) and Sharp-tailed Sandpiper (maximum 488 birds). The saltmarshes that surround the wetlands provide foraging habitat for Blue-winged Parrots (maximum 61 birds) (Birds Australia 2002). The near threatened Flame Robin and Diamond Firetail are occasionally observed in the IBA (Atlas of Australian Birds database).
Non-bird biodiversity: More than 360 species of plant have been recorded around the Natimuk-Douglas wetlands. This figure includes five species (Buloke, Bead Glasswort, Salt Paperbark, Hairy Tails and Dwarf Yellowheads) listed as threatened in Victoria under the Flora and Fauna Guarantee Act 1988 and three species (Bead Glasswort, Dwarf Yellowheads and Western Water-starwort) listed as nationally threatened under the Environment Protection and Biodiversity Conservation Act 1999. Nine species of reptile and six species of mammal (including the introduced House Mouse and European Rabbit) have been recorded around the wetlands (Birds Australia 2002).
Pressure/threats to key biodiversity
Determine potential impact of any future proposed expansion of salt mining operations. Monitor usage/removal of groundwater and the effect of this on water levels in the system. Investigate impact of recreational activities on waterbirds. Eradicate or prevent further spread of Canary Grass and other introduced pasture grasses. Investigate potential measures to mitigate salinisation. Investigate benefits of excluding livestock from wetland margins.
Conservation responses/actions for key biodiversity
A management plan has been prepared for the Natimuk-Douglas system (Birds Australia 2002). The system contains eight sites (Heards Lake, Mitre Lake, the Natimuk Lake-Natimuk Creek-Lake Wyn Wyn complex, Saint Marys Lake, White Lake, Bitter Swamp, Friedmans Salt Lake, Grass Flat [Telfer's] Swamp, Hatelys Lake [Swamp] and Olivers Swamp [Lake]) which are recognized as wetlands of national importance.
Numerous - see separate section.
State government and private. Most of the lakes in the IBA are situated within reserves managed by Parks Victoria.
Euan Moore wrote the nomination with input from Margaret Alcorn, Richard Alcorn and Dr Sutherland.
Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Natimuk-Douglas Wetlands (Australia). Downloaded from
https://datazone.birdlife.org/site/factsheet/natimuk-douglas-wetlands-iba-australia on 23/11/2024.
