An important hurdle to improving efficiency of commercial aquaculture is the lack of methods for reliably counting and sizing the stock. Compared to land, water is murky, and the livestock population is spread in three dimensions, making counting difficult. Reliable population and size information is essential for improving production efficiency and proper management of aeration and feeding. Hydroacoustical methods have often been proposed and tested for counting fish, and used in determining fish populations in natural waters. However, these methods have not been successfully adapted to commercial fish farming, where population densities are order(s) of magnitude higher, and wall and boundary effects on the acoustics significant. The proposed research combines a team of experts in the fields of experimental and computational, and aquaculture in a focused effort to overcome these problems and arrive at a practical hydroacoustic system. The proposed technique relies on change in the attenuation of low frequency modes of the waveguide formed by ponds/tanks. Compared to methods that use the resonance frequency response of individual fish swimbladders (much higher frequencies) the proposed method uses low frequencies and is likely to yield good results at higher fish density, lower acoustic frequencies, and lead to cheaper hardware.
Anticipated Results/Potential Commercial Applications of Research: Phase I will conduct laboratory tests and validate the theory and provide proof of concept, resulting in a laboratory prototype. Phase II will be directed at developing a commercial prototype and will be conducted in conjunction with a commercial fishery. A PC based system for counting and sizing fish, which is integrated into an overall system for managing the pond/tank will result. The system will be marketed to the large aquaculture industry that has expressed interest in the product.
