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Importance of the swimbladder in acoustic scattering by fish: A comparison of gadoid and mackerel target strengths
(Journal article; Peer reviewed, 1980)
Previous determinations of the swimbladder contribution to the fish backscattering cross section have been hindered by ignorance of the acoustic boundary conditions at the swimbladder wall. The present study circumvents ...
Acoustic scattering models of zooplankton
Rather-high-frequency sound scattering by swimbladdered fish
(Journal article; Peer reviewed, 1985)
A new model describes acoustic scattering by swimbladdered fish of lengths from at least 8 to 36 wavelengths. It represents a fish by an ideal pressure-release surface having the exact size and shape as the swimbladder. ...
Lateral-aspect target strength measurements of in situ herring (Clupea harengus)
(Journal article; Peer reviewed, 2009-07)
Surveys of schooling herring with the new multi-beam sonar (Simrad MS70) pose new challenges when converting the echo energy to estimates of biomass. Since the sonar projects horizontally, data and models of lateral-aspect ...
Maintaining precision calibrations with optimal copper spheres
(Journal article; Peer reviewed, 1983)
Effects of variations in quantities influencing the backscattering cross sections of solid elastic spheres are studied through a particular case. This is that of the 60-mm-diam copper sphere, which is being used worldwide ...
Bioacoustics and D. V. Holliday: a scientific tribute
Hydroacoustic performance of fishery survey instruments
Observing individual fish behavior in fish aggregations: Tracking in dense fish aggregations using a split-beam echosounder
(Journal article; Peer reviewed, 2007)
Acoustic instruments are important tools for observing the behavior of aquatic organisms. This paper presents a simple but efficient method for improving the tracking of closely spaced targets using a split-beam echosounder. ...
Acoustic sampling volume