The deaths have most likely been caused by low oxygen levels as floods recede,a situation made worse by fish needing more oxygen because of the warmer weather.
A flood peak laden with deoxygenated water is pouring into the Menindee Lakes system in Far West NSW,site of the catastrophic fish kills in 2019.
And a fish kill warning has been issued for the Darling River,with up to a million native fish at risk of being swamped by floodwaters.
The Berejiklian government has told other states it wants the operating rules of one of the Murray-Darling Basin’s biggest lake systems changed to cut the risks of mass fish kills on the Darling River.
Menindee Lakes,one of the largest lake systems in the Murray-Darling Basin,are filling fast with the biggest inflows in five years,allowing releases into the Baaka-Darling River downstream.
Residents of far-western NSW are gearing up for the arrival of floodwaters down the Barwon-Darling,giving Menindee Lakes its first big fill in five years.
A red-alert for toxic cyanobacterial blooms has been issued for almost the entire Lower Darling River,with fears another big fish kill is imminent without significant new flows.
The Menindee Lakes,1000 kilometres west of Sydney,need urgent protection to avoid another ecological disaster.
More than 60,000 Murray cod were returned to the Darling River near Menindee after hundreds of thousands of fish were killed two years ago.
After massive fish death events in multiple locations across the basin over the past 18 months comes a welcome restocking.