Influence of fishing intensity upon the composition of fish populations

Abstract

      The influence of fishing intensity upon the composition and size of fish populations is analyzed by the author of this paper.

      The study of the phenomenon involved some commercially important marine species and fish groups in the sounds along the eastern coast of the central Adriatic region from 1957 through 1958.

      The investigations have shown that the occurrence of a large proportion of predatory fish (Chondrichthyes) in a marine fishing area reflects the natural conditions existing in the sea concerned. These natural conditions are marked by the growing number of predatory species and by the decreasing number of commercially important ones (Osteichthyes).

       The ration is changed by action of man, i. e. by his engaging in fisheries. The value of a marine fishing area, consequently, is raised by rational fishing. This is confirmed, by the quantitative changes within various marine species­ and fish groups in the Adriatic.