Tube fishways aiding fish migration

You've heard of rock ramps, vertical slots and pool-types, but what about tube fishways?

Fish movement is essential for increasing genetic diversity in species and is critical to many species life cycle and breeding patterns. There are currently a variety of different fishways designed for improving fish passage which are tried and true, however the largest barrier to implementation (like with many things) is cost! Researchers from the University of New South Wales (UNSW) have been developing a new style of fishway that has not been previously seen in Australia. Supported by the Central Coast Council, Dr Jasmin Martino, a Research Fellow from the Centre of Ecosystem Science (School of Biological, Earth & Environmental Sciences), and PhD Student Hiruni Kammanankada from the Water Research Laboratory (School of Civil and Environmental Engineering) are developing a new, efficient and cost-effective solution for fish passage across river obstacles such as weirs and locks.

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A typical fishway at Cohuna Weir. Source: Pam Clunie, ARI

This novel technology acts as a bypass to instream barriers, utilising a self-powered water propulsion system. Unlike other fishway designs, this design can be retrofitted to existing structures without modification of the weir/lock. The method is cost-effective, easy to manufacture and install, and has minimal moving parts. This means that the Tube Fishway can be deployed and removed quickly, making it ideal for temporary installation during peak migration periods. The team at UNSW conducted a series of field experiments at Mangrove Creek and Ourimbah Creek in early 2024.

There are two key steps in the Tube Fishway process: attraction and transport. Fish are attracted into a pipe chamber using existing fishways’ knowledge to attract free-swimming fish into a chamber. Then, the transport process uses the acceleration of flows in the tube system to move the fish, vertically through a riser pipe over the wall.

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

Over a thousand fish were drawn to the experimental attraction unit. The data collected from the trial will help researchers understand the best conditions for attracting local native fish, such as Australian Bass, Flathead, Sea Mullet, and Freshwater Herring, into the tube system. The researchers plan to return to Mangrove Creek and Ourimbah Creek in Spring 2024 to test a full-scale model of the Tube Fishway, aiming to further support the migration of native fish species in these waterways.

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Click here to watch a report from NBN News on the new device.

“We conducted systematic design experiments to optimise attracting fish to piped systems. This is important fundamental research before the full deployment of the Tube Fishway that we aim to perform later this year.” Said Ms Kammanankada.

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Finterest will keep you posted on new developments with Tube Fishways!

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Resources

Field research develops native fish passage technology

New fishway set to improve Australian native fish migration

Tube fishway project