Potential estimation and exploitation of large Pelagics in the Persian Gulf and Oman Sea

Abstract

In order to come up with the responsible fishing pattern, there was a need to identify some of the biological characteristics and population dynamic parameters of yellowfin tuna, skipjack and longtail tuna in the Persian Gulf and Oman sea. Occurrence of empty stomach was high in all the specimens obtained from the gill net fisheries. Purple back flying squid was the most dominant prey species observed in the yellowfin tuna study (61% in males and 57% in females). The length of maturity (Lm50%) for yellowfin tuna was estimated 76 cm , 62.5 cm skipjack and 62.5 cm longtail tuna. Length range of skipjack was from 31-100 cm and bony fishes were the most dominant prey species observed in the skipjack. The monthly gonad somatic index was driven higher values after June which could be indicated as spawning period. The catch per unit of effort of three purse seiners (Azadegan 1, 2, 3) was compared in 1998- 2000. The species composition was 47% yellowfin tuna, 51% long tail tuna and 2% skipjack.