Innovating fishways through behavioural insights

Having long been an avid fishkeeper, PhD Candidate Yoel Jeremy has always had fascination for the diversity of behaviours exhibited by aquatic animals.

He was lucky enough to be involved in two behavioural research projects as an undergraduate student in Indonesia; both related to assessing the shell-selection behaviour of terrestrial hermit crabs. It was then that Yoel realised that the key to successful biodiversity conservation often lies in understanding the innate behavioural patterns of the species managed.

His research at UNSW builds on his experiences, exploring how the behaviour of fish can help to inform the design of novel fishway technology. Working on the UNSW Tube Fishway project under the supervision of Professor Iain M. Suthers, Associate Professor Stefan Felder and Professor Richard Kingsford; Yoel’s research is helping to establish a framework to develop and evaluate the performance of alternative fishway designs in Australia.

The objective of Yoel’s research is to utilise information on swimming performance to produce a cost-effective design that is efficient at aiding the passage of native fish communities through instream barriers like dams and weirs.

While there are many fish passages installed within Australian waterways, Yoel says they are not all fit-for-purpose.

“A great percentage of Australian native freshwater fishes are migratory; that is, they rely on moving from one habitat to another to grow, reproduce, and access critical resources; hence, physical barriers can directly affect their population fitness,” says Yoel.

“But most of the fishways in operation here are based on designs ‘imported’ from the Northern Hemisphere, and are ill-suited to pass native fishes. This is where our behavioural insights play a critical part in the development of novel fishway designs more suitable for our fishes here in Australia.”

Elaborating on how fish behaviour can impact fishway design, Yoel explains that our fish do not jump around like salmon do, so fishways that consist of a series of pools in steplike arrangements are not appropriate.

“We pursue closed-conduit fishways here due to Australia's climate and the extreme discharge fluctuations; open channel fishways can get completely dry during the dry seasons and are unusable by fish,” says Yoel.

“By using closed-conduit fishways we have more control over the volume of water going through the fishway at any given time; regardless of discharges."

The novel ideas from Yoel’s research and the broader Tube Fishway Project are intended to aid government agencies such as state government Departments of Primary Industries, as well as non-profit organisations and Traditional Owners who are managing land, wildlife, and resources. The Tube Fishway Project is funded by the Next Generation Water Management Hub led by Charles Sturt University, while Yoel is supported by UNSW’s University International Postgraduate Award—a higher degree research scholarship providing living expenses and tuition fees for a 3.5 year PhD.

When asked about his reasons for choosing to pursue his PhD with UNSW, Yoel says, “UNSW is one of the highest-ranking universities in Australia in terms of research outputs, so I think the real question should’ve been, ‘why not UNSW?’”

“I’ve been affiliated with the university since undertaking my Masters degree four years ago and I enjoyed the many opportunities to get involved in collaborative projects with other universities and institutions like the Sydney Institute of Marine Science and Taronga Conservation Society. Regardless of what you’re doing, these opportunities seem to just present themselves around here… so long as you actively put yourself out there, I guess!”

Yoel appreciates that his research is very closely linked to both the science and engineering disciplines, but he is truly a scientist at heart. In closing, he shares a quote that he believes reflects the essence of his research:

“Without engineering, science is just a theory. Without science, engineering is verschlimmbesserung."

Verschlimmbesserung (noun): a German word for an attempted improvement that only makes things worse.