Electroacoustic measurement of trawl net parameters

The dynamic characteristics of bottom trawl nets are currently being investigated by the Seattle office of the U.S. National Marine Fisheries Service to improve net design, rigging and handling. To aid in this study, an electroacoustic system to measure and store on digital tape several of the net parameters has been developed by the Applied Physics Laboratory, University of Washington. This instrumentation package is currently being used by the National Marine Fisheries Service in the Puget Sound area. Initial results indicate that a better understanding of bottom trawl net characteristics, especially at relatively deep depths, has resulted from the use of this equipment.