Session: 13-01-02 Blue Economy II

Paper Number: 125703

125703 - Designing for the Animal: Reimagining Offshore Fish Structures 

Finfish are an excellent source of protein with both wild and farmed fish playing a major role in meeting the current global demand. However, the world population is increasing and to meet the demand for this nutritional food, with the wild fish resource limited in growth due to factors such as pollution, overfishing and poor management, finfish aquaculture has a huge potential to fill the gap. Typically, optimal areas for finfish farms have been in nearshore marine environments where the sea-state remains slight such as can be found in semi-enclosed bays and harbours. However, these areas are now at a premium in many regions of the world meaning that the only way to supply the increasing demand for finfish is to move further offshore to open ocean aquaculture (OOA).

Traditionally, finfish structures have been designed from an engineering perspective to ensure that the structure is built to withstand the environmental loads that it will sustain. Many designs exist that can be fixed, floating, submerged or submersible. One common element with all designs is that they are fixed to the seafloor with a mooring. Moving offshore into more energetic seas will require new designs and technologies to be engineered to withstand the forces occurring from complex sea states, particularly during storm events. However, being fixed in one location will also limit what species can be grown due to temperature preferences. 

What if however, the aquaculture structure was designed from the fish's point of view? What elements do fish require to ensure that the environment is optimal for them? The New Zealand-based Whakapōhewa ki ahumoana Reimagining Aquaculture project (funded by the Ministry for Business, Innovation and Employment Endeavour Fund) led by Plant & Food Research, is designing a mobile aquaculture system for finfish. This paper outlines the new approach to finfish aquaculture – to build a mobile structure with the welfare of the fish at the centre of the design. Being able to move fish to conditions where they grow best will likely have significant benefits. Healthy fish grow faster and have lower rates of mortality as well as a reduced likelihood of being infected by diseases and parasites. Optimal temperature, flow velocities, water quality and high dissolved oxygen concentrations are key to healthy fish. Here we explore the environmental conditions that need to be considered when designing fish cages for the fish and provide some concepts to explore how we can undertake the development of finfish OOA in a sustainable way.

Presenting Author: Suzanne Black The New Zealand Institute for Plant and Food Research Limited

Presenting Author Biography: Suzy is a Senior Scientist/Team Leader for PFR’s Seafood Production Group within the Seafood Technologies Portfolio and is the programme leader in the MBIE Re-imagining Aquaculture programme. She has a PhD in Fish Physiology from the University of Canterbury, and over 20 years’ of experience in the development and industrial implementation of finfish capture, handling, and postharvest storage technologies. Understanding what a fish needs to be at its best has been the foundation of her research. Suzy is passionate about developing physiology-based technologies that make a difference in the real world and she enjoys working closely with industry partners to develop and operationalise solutions.

Authors:

Suzanne Black The New Zealand Institute for Plant and Food Research Limited
Ross Vennell Cawthron Institute
Louise Kregting The New Zealand Institute for Plant and Food Research Limited
Damian Moran The New Zealand Institute for Plant and Food Research Limited
Denham Cook University of Waikato Coastal Marine Field Station
Gerard Janssen AQUI-S New Zealand Limited