| Popis: |
Bioacoustic predictions of volume scattering strength Sv(z, f ) below 20 kHz due to mesopelagic swimbladdered fish contain errors arising from biological sampling limitations and uncertainties in swimbladder target strength. These predictions all utilize allometric equations relating, say, swimbladder equivalent spherical radius R to fish standard length l. Since the equations take no account of swimbladder size variability that is acoustically significant, the predictions contain ‘‘swimbladder variability error’’ (SVE) as well. New modeling procedures are presented to reduce SVE in Sv predictions for arbitrary size‐depth distributions of swimbladdered fish with gas‐filled swimbladders. It is assumed that the swimbladder size allometry properties of these fish, either as individual species or as a species class, can be described by appropriate bivariate normal density distributions p(x,y), where x=ln l and y=ln R, as suggested by recent results of Saenger (submitted to Can. J. Fish. Aquat. Sci.). SVE in p... |
