Area backscattering strength (Sa) values and the number of Japanese anchovies (n) obtained from each fish school.

Area backscattering strength (Sa) values and the number of Japanese anchovies (n) obtained from each fish school.从各鱼群获取的面积背散射强度（Area backscattering strength，Sa）数值与日本鳀（Japanese anchovies）的数量（n）。