Wetlands within the Northern Agricultural Region are critical sites of surface and groundwater interaction, acting as collection points for surface water runoff and providing recharge to groundwater.
In the NAR, many wetlands dry out completely during the summer but there are some which are continuously fed by groundwater which are extremely important transitory habitats for migrating birds as well as supporting significant permanent aquatic ecologies. The habitats in and around the wetlands of the NAR are highly sensitive to water chemistry changes caused by land use practices as well as changing hydrology from both land use and climate change leading to altered water regimes.
There are eight wetlands in the NAR that are listed on the Directory of Important Wetlands (Environment Australia, 2001). These wetlands are recognised as being Nationally significant
In addition, five wetlands were listed as being sub-regionally signiﬁcant in WA’s biodiversity Audit (Desmond and Chant, 2003) along with the wetlands described in the wetland atlas for the Swan Coastal Plain. Find out about these wetlands on the map below.
Click features on the map for more information. View full page map.
Data courtesy of the Department of Water and Department of Parks and Wildlife.
This wetland supports forty-two species of waterbirds and ranks in the top 4% of wetlands for number of species
A scenic water hole formed along the Greenough River, at the base of a rocky gorge. Ellendale Pool is popular for recreational activities and nature observation.
Freshwater Springs in Northampton area
Greenough River Pools
A good example of a large saline/brackish lake in the bioregion.
Hutt Lagoon System
Hutt Lagoon is a good example of a coastal brine lake which is an important site for migratory waders. At present, about 450 hectares of Hutt Lagoon’s approximately 2,500 hectares is being used to cultivate algae from which Beta-Carotene is extracted.
A good example of freshwater marsh dominated by low sedges and grasses; though this example is man-modified, the type is uncommon in south-western Australia
Lake Logue/ Indoon System
A good example of a suite of linked seasonal freshwater/brackish basins that occur in the bioregion. The System acts as a major feeding stop-over, staging area for dispersal and a drought refuge for waterbirds. A population of the declared vulnerable plant Eremophila microtheca (Nv, Sr) occurs on seasonally waterlogged ﬂats.
Lake Thetis is one of few lakes where both submerged benthic microbial mats and developing microbial structures occur. The shallow pools on the south western shore provide the perfect environment for the growth of micro-organisms, particularly cyanobacteria, which are the building blocks for stromatolites, the regions only example of ‘living fossils’. Stromatolites – layered rocks – are the oldest form of life on earth dating 3.5 billion years, although the Lake Thetis structures are relatively new, being about 2,000 years old. Stromatolites grow in Lake Thetis because of the extreme salinity and limited circulationof the water and the occurrence of calcium carbonate. Lake Thetis is a very important site in the region and a signiﬁcant example of a specialised form of aquatic ecological community.
A symposium on Western Australia’s south-west microbialites during October 2012 developed a number of methods of addressing the major issues with conservation management of WA’s microbialites and microbial assemblages including increased sharing of knowledge and community ownership.
Lancelin Defence Training Area
This is part of a regionally significant group, the Bassendean group, and is recognised for its conservational values. Due to its proximity to surrounding nature reserves and national parks and the large area of freshwater wetlands on the site, it is likely to support a relatively high diversity of wetland biota.
Murchison River (Lower Reaches)
A good example of permanent river pools set in a long, narrow, steep-sided gorge.
Saline lakes of Coolimba – Jurien
Wannamal Lake System
The system, though moderately disturbed, is a good example of a suite of wetlands of varied depth and salinity in the bioregion.
White and Green Lakes
Yerina Springs is a freshwater wetland fed by catchments to the north and west and provides critical habitat for flora species, such as the Endangered Long-leaved myrtle (Hypocalymma longifolium).