Media Release

18/01/2023

Cod study signals fish need more than ‘just add water’

The failure to find a single Murray cod in one stretch of the Darling River during recent monitoring signals native fish need more than just adding water.

“The Basin Plan assumes just taking more water from farmers is the silver bullet to fix everything,” said NSW Irrigators’ Council CEO, Claire Miller.

“But ecology is just not that simple. Degradation has many complex drivers requiring a comprehensive integrated catchment management program to address, such as habitat restoration for native fish breeding, and invasive species control.”

Ms Miller said locals have observed Murray cod breeding up as the recent floodwaters have moved through the Basin rivers, reflecting DPI reports of improving abundance over the last 20 years.[1]

“This iconic species can recover in this stretch of the Darling River, too, with the right management actions, but not if governments are not prepared to pull any other lever than just more water recovery.”

Fish scientists have attributed the decline to a range of factors, such as ‘the impact of introduced carp, the removal of habitat which fish used to breed in the river, the presence of weirs that obstructed fish migration, overfishing and poor water quality’.

“Buybacks won’t fix these key degradation drivers,” said Ms Miller. “Without a comprehensive plan to address these drivers, further buybacks would just be tinkering at the edges.”

“Where is the same sense of urgency, funding and political will to address these key degradation drivers, as we see with water buybacks?

The call comes as the irrigation community grow increasingly frustrated that the sacrifices made under the Basin Plan and other reforms, to return 1 in 3 litres of irrigation water to the environment, cannot deliver optimal results until more is done on complementary measures.

“Irrigators have given up so much, 1 in 3 litres, that’s enormous, and what they want to see in return is healthy thriving river systems, and the recovery of native species,” said Ms Miller.

NSWIC is calling on the Basin Ministerial Council to prioritise funding for ‘complementary measures’ when it meets next month, such as habitat restoration[2], improved fish passage, fish screening, invasive species control, to make the most of water recovered under the Basin Plan.

“Governments have done the water recovery part (2100 billion litres, or more than four Sydney Harbours), but not the on-ground measures – they must go beyond buybacks, and put money where the problem is”.

Leading scientists have long been calling for this, with a peer-reviewed paper stating: “We argue that while recovering water will provide good outcomes, as a sole intervention, it is not enough to deliver the desired environmental benefits of the reform… In a highly modified system, equal attention should be given to addressing other threats that water delivery alone cannot ameliorate.” [3]

Total diversions for irrigation, towns and industry in the Basin are now down to just 28% of inflows, well within international standards for a healthy river system.

“It’s time we move forward and look at the other issues in the Basin too, which have overtaken the simplistic ‘just add more water’ mantra,” said Ms Miller.

“If the problems aren’t properly understood, the solutions won’t work, and the biggest loser is the environment, and the farmers and communities who live, work and play in that environment.”

________________________________________
[1] https://2rog.com.au/wp-content/uploads/2023/01/Bringing-Back-Murray-Cod-to-the-Baaka-1.pdf
[2] For example, Dr Banks , the CEWH, has said: “Murray Cod use large woody habitat for spawning sites, shelter and territorial markers. Detailed habitat mapping undertaken in partnership with DPI Fisheries has identified priority areas along the reach to put logs and branches back in the river for fish. We are working with DPI Fisheries to explore opportunities to support re-snagging activities in the Darling-Baaka.”
[3] https://onlinelibrary.wiley.com/doi/abs/10.1002/rra.3438
________________________________________

Secure - Sustainable - Productive