Conditions influencing Waterbirds in the Vasse-Wonnerup Wetland, Western Australia: Implications for Water Regime Management
Department of Water and Environmental Regulation
School of Science
The Vasse-Wonnerup Wetland located in the South-West of Australia is recognised as a “Wetland of International Importance” under the Ramsar Convention and hosts tens of thousands of waterbirds each year. The wetland comprises the Vasse and the Wonnerup Estuaries and their exiting channels.\ Two surge barriers were constructed between the estuaries and Wonnerup Inlet at the beginning of the 20th century to prevent seawater incursion to surrounding agricultural lands. Due to nutrient enrichment and altered flows caused by river diversions and land drainage, and the surge barriers reducing flushing water flows, the system has experiences episodic algal blooms, anoxia and fish deaths. Since the late 20th century, the surge barriers have been opened in summer as part of a water management regime to allow fresh sea water input into the system to improve conditions.