Preliminary observations on the productivity of certain Tuna waters off the west coast of India

Abstract

It is well-known that in dealing with major oceanic fisheries like that of tunas, billfishes, etc., we have to take into account a very complex ecological system. Researches and surveys hitherto carried out with regard to the tuna fisheries have had as their main object the extension of present fishing grounds and discovery of new ones. Though it could be noted that some variations take place from year to year in the position of the centres of good fishing and in their relative importance, the geographical patterns of catch distribution seem to be rather permanent features. It has been found often that some particular areas have been consistently yielding good catches of tuna though the reasons are not known in detail.