A novel quantitative method for assessment of main food components (mysids and zooplankton) for commercial pelagic fish (herring and sprat) using multi-frequency (MF) hydroacoustics was developed, and accuracy of acoustic fish stock assessments was enhanced through improving methodology. Algorithms to differentiate fish, mysids and zooplankton in MF acoustic data were developed. An updated conversion factor linking acoustic parameters and fish biomass was developed for the Baltic.

Workpackage indicators:
1. Multi-frequency hydroacoustics system purchased, installed and calibrated
2. Developed algorithm to differentiate fish, mysids and zooplankton

More about workpackage:
Technical Report No. 1: "Surveillance of marine resources using multi-frequency hydroacoustics"

Responsible for implementation:
Coastal Research and Planning Institute
University of Oslo, Department of Physics

Contact: Dr. Tomas Didrikas (tel.: +46 8161353, e-mail: tomas@ecology.su.se)