Measurements of sound scattering as a means of examining ecological interactions between marine organisms and their environment

Significant advances in hydroacoustic systems have occurred in recent years and the availability and application of such systems has greatly improved the quality of quantitative sound scattering measurements from towed and moored sensors. There remain questions of relating the quantity of sound scatter observed (a highly precise measurement) to the quantity of biota or other material causing reflections or volume reverberation (a less well understood process, where behavior of the ensonified organisms causes variation in their target strength). Measurements of sound scattering coupled to directed sampling of target organisms (using nets or video) frequently reveals many aspects of interactions between organisms and their environment. This paper presents methods and examples of measurements and comparisons between sound scatter, causative organisms, and environmental data