RT - Journal Article T1 - Population dynamic parameters of Thunnus tonggol (Bleeker, 1851) in the Persian Gulf and Oman Sea JF - IFRO YR - 2013 JO - IFRO VO - 12 IS - 4 UR - http://jifro.ir/article-1-1358-en.html SP - 855 EP - 863 K1 - Growth and mortality parameters K1 - Thunnus tonggol K1 - Persian Gulf K1 - Oman Sea AB - Length frequency data of the longtail tuna, Thunnus tonggol collected from October 2006 to September 2007 were analyzed for evaluation of the stock parameters. T. tonggol is mainly caught by gillnet method. Yearly tuna and tuna-like catches in Iran are of the order of 174,234 mt, close to 46% of which are longtail tuna. The VBG parameters for longtail tuna were: L∞ =133.72cm K=0.35 year−1.The length –weight relationship was estimated as: W=0.00002 L 2.83.The instantaneous rates of total mortality (Z) was estimated by using the Powell-Wetherall plot as 1.82 year−1. The instantaneous rate of natural mortality was obtained by Pauly equation (M=0.44 year−1) and the instantaneous rate of fishing mortality (F) estimated from Z-M=1.38year−1. LA eng UL http://jifro.ir/article-1-1358-en.html M3 ER -