Following trying times, native fish are bouncing back in the Baaka…
We all remember those images from the mass fish deaths that occurred in summer 2018-2019 in the Lower Darling Baaka River along the Menindee town weir pool. To understand how this event impacted local fish communities, NSW DPI Fisheries has been monitoring the Lower Darling Baaka since June 2019.
Initial results showed the fish deaths had a dramatic impact on local fish populations, with most species suffering declines in the Menindee weir pool. A few species like Australian smelt and the pest species Carp were less affected, and this is because they can occupy the thin layer of oxygenated water at the river’s surface. Ultimately though, their numbers also declined through 2019 as water quality in the Menindee weir pool continued to deteriorate.
Through 2019, the Lower Darling Baaka downstream of Menindee contracted to a series of isolated waterholes and a progressive decline in the fish community (including Murray cod, Golden perch and even Carp) was recorded.
But then…. the Lower Darling Baaka started to flow again.
In 2020, flows returned to the Lower Darling Baaka and Menindee Lakes, restoring river habitat and generating the food fish need to begin the long road to recovery. Smaller bodied native fish like the Australian smelt began to show signs of recovery soon after flows returned in March 2020, with monitoring detecting young fish – an indication of recent breeding efforts.
Fish community recovery in the Lower Darling Baaka has been further enhanced by environmental flows to the Lower Darling Baaka designed to support breeding and recruitment of native fish (particularly Murray cod and golden perch). Re-stocking of Murray cod and golden perch fingerlings (bred from adults rescued from the Lower Darling Baaka in 2019) has also been conducted to further assist recovery of these iconic species.
Monitoring in Lake Cawndilla by DPI Fisheries, Baakandji River Rangers and community groups, has confirmed juvenile Golden perch are now fattening up in this highly productive lake. With good numbers of Golden perch, there is now an opportunity for us to add some environmental flows along the Great Darling Anabranch that connects Lake Cawndilla to the Murray, enabling a boost to Golden perch stocks well beyond the Lower Darling Baaka.
Environmental water managers, alongside NSW DPI Fisheries, local communities and the Lower Darling Baaka Recovery Reach team are working together to deliver flows, restore habitat and bring native fish back to this special stretch of river. Community involvement has been vital in the fish recovery efforts (including some of our youngest fish monitoring recruits in the above photo!), assisting initially with fish rescues during the drought and more recently with fish re-stocking and monitoring of water quality.
Featured image: A flowing Lower Darling Baaka River, May 2021. Source: NSW DPI.
Lower Darling Baaka Recovery Reach
This Recovery Reach is significant for native fish in the Murray-Darling Basin, home to iconic species such as Golden perch, Murray cod, Silver perch and Freshwater catfish, as well as a number of important small-bodied native fish species.