Acoustic scattering by fish in the forward direction

This article is a study of the scattering of sound by fish in the forward direction. It is shown that in contrast to the situation with backscattering, the fish body rather than the swimbladder is primarily responsible for forward-scattering at high frequencies. In addition, the forward-scattering function of fish has a simple structure compared with the backscattered signal. Since the shape of a fish body is relatively easy to obtain, models for which the fish body is the major target are expected to be superior to those based on the swimbladder. More experimental work on the forward-scatter of sound by fish would seem worth while. Comparisons are made with the acoustic backscattering by fish. (C) 1996 International Council for the Exploration of the Sea