Dead fish have also been reported at Wyangala Dam following a large fish kill at Menindee in Western NSW.
Tthe NSW Department of Primary Industries (DPI) and WaterNSW are investigating the Menindee fish kill.
In a statement released this week DPI said in recent weeks fish kills have also occurred in the Namoi River below Keepit Dam, the Lachlan River at Wyangala Dam and also in the the Darling River at Menindee in a separate event in December.
“The ongoing drought conditions across western NSW have resulted in fish kills in a number of waterways recently and today our fisheries officers have confirmed a major fish kill event in the Darling River at Menindee affecting hundreds of thousands of fish, including Golden Perch, Murray Cod and Bony Herring,” DPI Senior Fisheries Manager, Anthony Townsend said.
“After a very hot period, a sharp cool change hit the Menindee region over the weekend, with large temperature drops experienced.
“This sudden drop in temperature may have disrupted an existing algal bloom at Menindee, killing the algae and resulting in the depletion of dissolved oxygen.”
Mr Townsend said preliminary investigations by DPI into the current fish kill event suggest that hundreds of thousands of native fish have been impacted in the same stretch of waterway and further downstream.
WaterNSW is continuing to monitor water quality.
Adrian Langdon, WaterNSW executive manager of systems operations said regional NSW is experiencing intense drought conditions, with the state’s Central West, Far West and North West regions the worst affected.
“Algal alerts have been in place for several weeks in the Menindee region and linked to this, low dissolved oxygen levels are likely to occur within slow flowing or no flow sections of the river,” Mr Langdon said.
Community members are encouraged not to be alarmed and to report any similar incidents or observations through the Fishers Watch hotline on 1800 043 536.