The protection of the hake (Merluccius merluccius L.) in the Adriatic Sea by regulation of the level of exploitation

Abstract

        Dealing with the statistical data of the total hake (Merluccius merluccius L.) annual catch in the Adriatic sea and corresponding estimated fishing effort for the period from 1959 to 1978 year using the concept of the production models; linear (S c h a e f e r, 1954) and exponential (F o x, 1970), it has been tried to assess values of maximum sustainable yield (MSY) and optimal fishing effort (f_OPT), for management purposes.

        Achieved values of maximum sustainable yield for the hake population in the Adriatic sea ranged: from 2.818 to 3.273 tons per year with corresponding fishing effort: from 54.348 to 62.632 fishing days per year. 

        Values of the total mortality coefficient (Z) obtained by Gulland’s method (G u l l a n d, 1968) for the period 1970-1979, equals (Z = 0,79) on the average. On the basis of bottom trawl selectivity experiments (Granić and Jukić, 1980), in Adriatic non selective trawl fishery, using approaches      B e v e r t o n and H o l t (1956) it has been estimateed mortality coefficient (Z = 0,77).