ABSTRACT
The quantitative estimation of readings of acoustic instruments is important in determining fisheries resources, in studying biological regularities of the distribution and behavior of aquatic animals, and in fisheries for detecting the densest areas of concentrations and their targeted catching. Calibration of the acoustic equipment for the quantitative estimation of concentrations of fish and other marine items represents a complex of steps, carried out for the purpose of determining the main parameters of the equipment and for controlling their stability. Measurements of the acoustic section of an individual item are the most complicated step of the calibration. Through calibration is applied only when there is an absence of enough precise data on the acoustic section of items forming concentrations, and it is impossible to carry out their measurement in situ. The chapter considers the main peculiarities of the step-by-step and through methods of calibration of the equipment, as well as of their intercalibration.
