Peel-Yalgorup system. 07/06/90; Western Australia; 26,530 ha; 32°49'S 115°42'E. National Park. A large system of shallow estuary and saline, brackish and freshwater lakes that is used by tens of thousands of waterbirds, including large numbers of migrant shorebirds from the northern hemisphere. Vegetation consists of fringing, samphire flats giving way to rushes, sedges and trees tolerant of water logging (Melaleuca, Casuarina), with open woodland (Agonis, Eucalyptus) on higher ground. The site is the most important area for waterbirds and waders in Southwest Australia, regularly supporting over 20,000 individuals. The system supports a regionally important estuarine fishery. There are unique formations of calcium carbonate, and the site is one of only two in southwestern Australia and one of very few in the world where living thrombolites (a type of microbialite, superfically resembling stromatolites) occur in hypersaline water. The area is used extensively for recreational purposes. Site's area significantly extended on 05/01/01. Ramsar site no. 482. Most recent RIS information: 2000.