Authors
Tim E Ryan, Rudy J Kloser, Gavin J Macaulay
Publication date
2009/7/1
Journal
ICES Journal of Marine Science
Volume
66
Issue
6
Pages
1238-1244
Publisher
Oxford University Press
Description
Ryan, T. E., Kloser, R. J., and Macaulay, G. J. 2009. Measurement and visual verification of fish target strength using an acoustic-optical system attached to a trawlnet. – ICES Journal of Marine Science, 66: 1238–1244.
It is difficult to make acoustic target-strength (TS) measurements of fish behaving naturally in deep-water habitats. The fish may avoid the acoustic instrumentation, and, if measured, there is uncertainty about their species and their orientation relative to the incident sound. To address these issues, a novel acoustic-optical system (AOS) has been developed, which combines a battery-powered, dual-frequency, split-beam acoustic system with a low-light video camera. The AOS attaches to the headline of a commercial deep-water demersal trawlnet that herds fish past the AOS and to the codend. This paper describes initial trials of the AOS to measure calibrated TS of New Zealand …Total citations
Scholar articles
TE Ryan, RJ Kloser, GJ Macaulay - ICES Journal of Marine Science, 2009