Juvenile Golden perch sampled in the Menindee Lakes system in autumn 2021. Photo: DPI Fisheries
With the Menindee Lakes filling with both water and fish, water for the environment is being released throughout spring to help native fish in the Lower Darling-Baaka River and the Great Darling Anabranch.
Golden perch (aka Yellowbelly or Callop) spawned in northern rivers of the Murray-Darling Basin (e.g. the Warrego, Condamine, and Barwon-Darling rivers) during high flows in early 2020 and again in early 2021. Many of these travelled downstream with the flow all the way to the Menindee Lakes. Researchers have confirmed that juvenile Golden perch are currently fattening up fast in the Menindee Lakes – regarded by fish ecologists as a key fish nursery in the basin. Some have already moved further downstream into the Lower Darling-Baaka River itself during the various releases made over the last 12–18 months.
The 2021 Great Darling Anabranch flow is starting in spring and creating a ‘Golden Highway’ for juvenile golden perch and other native fish in Lake Cawndilla to move down the Anabranch and disperse throughout the Murray valley.
This is the first flow down the Anabranch since 2017, providing a much-needed drink for the local environment. In addition to supporting fish movement, the flow is also expected to provide benefits for plants along the Anabranch and create additional feeding grounds for ducks and other waterbirds.
The Menindee Lakes have filled with both water and fish
The Menindee Lakes have filled with water and fish, and for the first time since 2017, water is flowing into the Great Darling Anabranch, providing native fish the opportunity to migrate into the Murray Valley.
The 2021 Lower Darling-Baaka spring fish flow will also use water for the environment to give juvenile Golden perch in the lakes additional opportunity to migrate down the Lower Darling-Baaka River to the Murray River, contributing to stocks in South Australia, northern Victoria, and the NSW Murray.
But there’s more! As well as promoting Golden perch migration, the 2021 Lower Darling-Baaka spring fish flow will continue to support the recovery of the local Murray cod population by providing optimum breeding opportunities.
Last spring (2020) water for the environment supported strong breeding by Murray Cod, and subsequent monitoring has confirmed lots of juveniles are developing in the Lower Darling-Baaka River.
Last year’s environmental flow in the Lower Darling-Baaka River maximised nesting sites used by Murray cod (e.g. under snags, rocks, and undercut banks). Water for the environment also inundated beaches and benches within the river to increase productivity and food (plankton) for tiny Murray cod larvae and created shallow slack water habitats in which developing juvenile cod can hide.
Left: Murray cod eggs laid on rocky surfaces in the river. Right: Juvenile Murray cod sampled in the Lower Baaka in March 2021. Photos: DPI Fisheries
Major fish kills occurred in 2018–20 near Menindee and subsequently downstream as the river contracted into dwindling refuge pools. The 2021 Lower Darling-Baaka spring fish flow is a positive step towards restoring the mighty Lower Darling-Baaka River back to a functioning healthy river.
The flows in the Lower Darling-Baaka and the Great Darling Anabranch are being delivered with careful planning and collaboration with the local community, NSW Department of Planning, Industry and Environment – Energy, Environment and Science (DPIE EES), the Murray-Darling Basin Authority, WaterNSW, NSW Department of Primary Industries - Fisheries, as well as fish ecologists from NSW National Parks and Wildlife Service and the Victorian Arthur Rylah Institute.
Regular updates on the both flows will be published as they become available.
For more information, please contact our Local Engagement Officer:
For further information on the Lower Darling-Baaka:
Lower Darling-Baaka and Great Darling Anabranch event updates
Lower Darling-Baaka and Great Darling Anabranch event update 1
After the Menindee Lakes reached capacity in September, water is being released down the Great Darling Anabranch for the first time since 2017.