Use of acoustics in studies of fish reaction to imposed stimuli

Abstract

The general distribution pattern of fish in a large holding pen is described through the integrated echo intensity in six separate cells using transducers mounted below the pen. The reaction of fish to different stimuli, imposed in one of the cells, is quantified by the change in frequency distribution of the echo intensity relative to the undisturbed situation. The experiment was part of a small-scale test of equipment to be used for observations of the attraction-effect of fish to oil-rig structures. The method also seems to be suitable for general fish behaviour studies, particularly concerning attraction and avoidance effects.