While multiple practices have contributed to this decline, the impact of fish losses at water diversions has been largely unappreciated and remains unaddressed. Native fish species are particularly vulnerable to irrigation offtakes, especially at the egg and larvae stages.
There is evidence that millions of native fish are lost each year from water bodies within the Murray Darling Basin as they are sucked into pumps or diverted into channels1.
Since 2012, fisheries managers and researchers within Australia, particularly at NSW DPI Fisheries, have been promoting the need to install fish screens on irrigation pumps, the positive results that could be achieved and how fish screens are necessary to protect the native fish within the Murray Darling Basin.
In many parts of the world, including the United States of America, Europe, and New Zealand, diversion screens are considered a critical component of any best-practice, whole-of-farm approach to irrigation modernisation. Large investments have been and are continuing to be made within these countries in installing self-cleaning screens. This means when they screen out fish, they also screen out debris which saves time and money through more efficient pump operation and lack of blockage of sprinkler systems.
To improve community and industry understanding of the necessity of fish screens in Australia and to achieve the progress required to increase fish populations by achieving industry uptake of the screening technology, all key stakeholders in river and fish management need to closely work together.
OzFish Unlimited are joining forces with key stakeholders particularly the irrigation sector broadly and the cotton industry, in particular, to implement a successful engagement program to ensure the sustainable and long-term improvement of native fish populations through the installation of fish screens.
Native fish are being lost from our rivers and creeks down irrigation channels. To stop this, irrigation diversion screens, are being trialed between the Gunbower Creek and Cohuna Channel. Watch the video about this amazing project, the first of its kind in Australia, that is saving our native fish.
New fish screens being tested in Victoria and NSW may reduce the annual loss of millions of fish, turtles and even platypuses in the nation's irrigation pumps and channels. Trials of the sophisticated self-cleaning mesh domes at Cohuna near the Murray River in Victoria are looking promising two years in. Another is under way at the Trangie-Nevertire Irrigation Scheme, north-west of Dubbo in NSW.
In March 2020, OzFish Unlimited produced TEDx style talks by leading experts passionate and knowledgeable about fish and fishing. They outline issues important to fish and how local communities can help protect and enhance fishing habitats across the country. The first series focused on the Murray-Darling Basin. Dr Craig Boys talk, Screen For Streams discusses, the impact of the loss of millions of native fish who got sucked into pumps and swept down irrigation channels – stranding them in fields and paddocks. With them comes debris that chokes pumps and clogs spray systems.
1Baumgartner L and Boys C (2012) Reducing the perversion of diversion: Applying world‐standard fish screening practices to the Murray–Darling Basin Ecol Mgt and Rest 13: 135 -143