Improving native fish migration

Dr Jasmin Martino and Hiruni Kammanankada from the Water Research Laboratory and The Centre of Ecosystem Science at UNSW

Central Coast Council is collaborating with the University of New South Wales (UNSW) in testing a new way to encourage Australian native fish to move across creek and river weirs, improving native fish migration.

Council Director for Water and Sewer Jamie Loader said Mangrove Creek and Ourimbah Creek would be included in pilot tests of the new design being conducted across the country.

“The Central Coast’s waterways are valuable water resources and ecosystems that support our drinking water supply, and Council’s weirs are essential mechanisms in the water harvesting process,” Loader said.

“Central Coast Council Water and Sewer supports efficient and cost-effective approaches in building a sustainable and resilient water future, including minimising the impact of water harvesting upon the environment.

“If fishway tests are successful, the new design could support and improve our existing mechanisms in our creek weirs.”

Unlike alternative fishways, the Tube Fishway works through a self-powered, water propulsion design that could offer greater benefits compared to other fish passage options, as it is cost effective to manufacture and install; is more easily retrofitted to existing structures; offers simplified maintenance as there are minimal moving parts in its design; can be scaled up and installed on high-level dams; and can be deployed and removed rapidly allowing temporary installation during peak migration periods.

PhD student Hiruni Kammanankada and supervisor Dr Jasmin Martino, from the Water Research Laboratory and The Centre of Ecosystem Science UNSW Sydney, are part of a team of academics designing and testing the Tube Fishway in accordance with regulatory bodies.

“Across January to March this year, in Mangrove and Ourimbah creeks we conducted systematic design experiments to optimise attracting fish to piped systems,” Kammanankada said.

“This is important fundamental research before the full deployment of the Tube Fishway that we aim to perform later this year.

“We successfully attracted 1,089 fish to our attraction unit across both sites.

“From this data we aim to crack the secret of what are the best conditions to attract local native fish such as Australian bass, flathead, sea mullet and freshwater herring into piped systems.”

UNSW will return to Mangrove Creek and Ourimbah Creek to further test the Tube Fishway in September in preparation for the fish breeding migratory window in Spring/Summer 2024/25.

Whereas earlier testing focused on attracting the fish to the tube, experiments in September will focus on lifting the fish over the weirs.

Administrator Rik Hart said that collaboration with UNSW’s Water Research team supported Council’s long-term vision and its Water Quality Program.

“Council is committed to seeking new opportunities and partnerships that contribute to regional health and prosperity,” he said.

“Collaborating with UNSW is another example of continual improvement of Council’s Water and Sewer department in supporting a sustainable water future.”

The project is funded by State Government grants including NSW Government Recreational Fishing Trust.