Scientists asked to investigate the fish kills in the Murray-Darling River system in NSW say a failure to act resolutely and quickly on the fundamental cause—insufficient flows—threatens the viability of the Darling, the fish and the communities that depend on it for their livelihoods and wellbeing.
The multidisciplinary panel of experts, convened by the Australian Academy of Science, also found engagement with local residents, Indigenous and non-Indigenous, has been cursory at best, resulting in insufficient use of their knowledge about how the system is best managed.
The scientists say their findings point to serious deficiencies in governance and management, which collectively have eroded the intent of the Water Act 2007 and the framework of the Murray-Darling Basin Plan (2012).
Chair of the expert panel, ANU Professor Craig Moritz FAA, said the sight of millions of dead fish from the three fish kills was a wake-up call.
“To me, it was like the coral bleaching event for the mainland,” Professor Moritz said.
“Our review of the fish kills found there isn’t enough water in the Darling system to avoid catastrophic outcomes. This is partly due to the ongoing drought. However, analysis of rainfall and river flow data over decades points to excess water extraction upstream.”
The expert panel recommends that urgent steps can and should be taken within six months to improve the quality of water throughout the Darling River.
“That should include the formation of a Menindee Lakes restoration project to determine sustainable management of the lakes system and lower Darling and Darling Anabranch,” Professor Moritz said.
The panel also recommends a return to the framework of the 2012 Murray Darling Basin Plan to improve environmental outcomes.
“The best possible scenario is water in the Darling all the way to the bottom and in most years. We are hopeful that this could be achieved if the panel’s recommendations are implemented,” Professor Moritz said.
Australian Academy of Science President, Professor John Shine, said the scientific advice of the expert panel is a synthesis of the best available knowledge.
“In undertaking this body of work the multidisciplinary expert panel has collaborated with other relevant experts as required and received extensive data from a number of Federal and State agencies,” Professor Shine said.
These agencies include the Murray-Darling Basin Authority, the Land and Water Division of the NSW Department of Industry, the NSW Office of Environment and Heritage, the NSW Department of Primary Industries, the Queensland Department of Natural Resources, Mines and Energy, and the Commonwealth Environmental Water Office, in addition to data and information provided by researchers in many related fields. The expert panel wishes to acknowledge the cooperation of these bodies and individuals in promptly providing data.
The expert panel also operated closely with the Independent Panel to Assess Fish Deaths in the Lower Darling, initiated by the Government and chaired by Professor Robert Vertessy, including sharing data and a reciprocal review of findings.
The main findings and recommendations are in the executive summary. The report was independently assessed by seven independent peer reviewers, including one international reviewer.
© 2023 Australian Academy of Science