Селективные свойства кутков тралов на промысле речной камбалы в Балтийском море.

Abstract

The results of investigations on selective properties of bottom trawls with mesh size (2a) 80, 90, 100, 110, and 120 at flounder fishery in the subdivision 28 of the Baltic Sea (1975—1977) are described. The influence of the inner mesh size (B) on the total fish length of 50 % sifting, size composition of fish stocks (length and young fish abundance modes) on the percentage of noncommercial fish bycatch and catch size on selective properties of cod-ends was determined. The dependences between flounder total length and other biometrical sizes (the girth behind gill covers and maximum girth, maximum body width and thickness) are revealed. Empirical formulas of the listed dependences are given. The recommendation on the expediency of transition to the higher selectivity level are given (the increase of mesh size in codends to 110 mm).