Martin Bend Wetland to Begin Drying Phase
The permanent lagoon at Martin Bend wetland has been temporarily disconnected from the river in order to start an essential wetland drying phase.
The drying phase is a critical feature for wetland health, but the installation of locks and weirs has significantly altered the natural ebb and flow of water into the river’s wetlands and floodplains. Many wetlands are now managed to mimic natural variation in water flow in order to maintain the conditions on which native wetland ecosystems depend.
Drying Martin Bend will also remove a large number of carp that entered during recent river high flows. As bottom feeders, carp cause significant damage to aquatic ecosystems by stirring up the bottom of the river bed, creating muddy water. Fish screens fitted to the regulator will be closed when the wetland refills to prevent all but the very smallest carp from re-entering the wetlands.
Martin Bend is a complex of wetlands that includes several distinct wetland types. The permanent lagoon receives water from the main river channel, while 3 temporary basins (ephemeral wetlands) connect naturally to the river during periods of high flows, and the stormwater lagoon receives rainfall run-off from the township.
The entire Martin Bend floodplain was completely inundated during the 2022-23 flood, so the area is now benefitting from a drying event, allowing natural ecological processes to occur.
“The last time we dried the permanent lagoon was in 2020, so it’s definitely due for its next drying phase,” said Annie Kriesl, Wetlands Project Officer with the Murraylands and Riverland Landscape Board.
“Drying is an important part of improving the ecological condition of the lagoon. It allows the wetland bed soils to dry out and consolidate, and gives vegetation the opportunity to expand on the newly exposed wetland bed. The drying phase sets up the wetland to flourish with productivity once it’s refilled” said Ms Kriesl.
Martin Bend wetland is a site of significant ecological value, providing important habitat for a variety of local native species.
“Once the lagoon is refilled, it will be abundant with aquatic vegetation which provides habitat and food for native fish, frogs and turtles”.
“Bird species will also benefit during the dry phase as shallow water and mud flats create feeding opportunities for wading birds such as spoonbills, ibis and stilts” said Ms Kriesl.
Martin Bend wetland is a popular place for both locals and tourists to visit. Featuring a walking trail loop, visitors gain a unique perspective of the area with the chance to get an up-close view of a wetland ecosystem.
“Visitors who use the walking trail around the permanent lagoon will notice it drying out over the next 9 months. It’s anticipated that the regulator will be re-opened in spring 2024”.
The Murraylands and Riverland Landscape Board’s Wetlands Program is involved in the management of more than 85 wetland sites across the region, including Ramsar wetlands of international significance The team is responsible for sustaining the health of wetlands and floodplains through the delivery of environmental water, and monitoring native flora and fauna to ensure native ecosystems are able to thrive now, and into the future.
This project is supported by the Murraylands and Riverland Landscape Board through funding from the landscape levies.