Growth, Mortality and exploitation ratio of Auxis thazard (Lacepède, 1800) in the Northern Persian Gulf and Oman Sea waters (Hormozgan Province Zone)

Auxis thazardis one of species of scombridae family in the Persian Gulf and Oman Sea. In order to come up with the responsible fishing pattern, there was a need to identify some of characteristics and population dynamic parameters. Data were collected randomly from three major artisanal fish-landing sites Bandar Sirik, namely Bandar Abbas and Bandar Lengeh in Hormozgan Province, from April 2016 to March 2017. The average fork length estimated 33.9 cm. The "a" and "b" parameters in Length- Weight relationship were estimated 0.000002 and 3.3 respectively and showed that A. thazardhas allometric growth. The growth parameters of L∞, K and t0 were computed 53.2 (cm), 0.8 (1/year) and -0.17 year respectively. The fork length attained at the end of 1, 2 and 3 years to be 32.3, 433.8 and 48.1 cm respectively. Growth performance index calculated 7.7 which was in agreement with the finding of the other studies. Total mortality, natural mortality and fishing mortality were estimated 2.45, 1.03 and 1.42 (1/year) respectively. The Fopt and Flimit as biological reference point were calculated 0.52 and 0.68 (1/year) respectively. The exploitation ratio was estimated 0.58.