Fish sizing and monitoring using a stereo image analysis system applied to fish farming

We describe and discuss a non-invasive 3D measurement technology based on optical stereoscopy and computer image analysis for continuous monitoring of size, position, shape, and spatial orientation of single fish in cages containing many fish. We provide limited initial results to demonstrate that fish dimensions may be measured to millimetre accuracy and that fish may be tracked over limited time intervals to observe detailed movement. We discuss how this may be developed to monitor whole fish stocks in a fish farm. Advantages and limitations of this technology are discussed in comparison to other currently available systems. The impact on aquaculture of this type of system for accurate and continuous monitoring is discussed.