Growth and mortality of new exploited stock of the blackmouth croaker, Atrobucca nibe (Jordan Thompson, 1911) from the Oman Sea

Some population dynamic parameters of Blackmouth croaker, Atrobucca nibe (Jordan Thompson, 1911), were investigated monthly from September 2013 to August 2014 in the Northwest of the Oman Sea. A total of 1685 length-frequency data were collected by the midwater trawl method. The average total length was 28.7±5.9cm; ranging from 18.0 to 47.5 cm. The most frequent length class was calculated 24-26cm. The length-weight relationship was found as W= 0.00895L3.0256, showing an isometric growth. Growth parameters of L∞ and K were estimated at 50 cm and 0.20 yr-1, respectively. Parameters of t0, Tmax and Ǿ were calculated -0.70 year, 14 years and 2.69, respectively. This species has two recruitment periods, a major peak occurred at 23.14%. Three cohorts were distinguished annually with a mean length of 24.16, 34.41 and 41.48 cm. Total, natural and fishing mortality rates were calculated 0.54, 0.46 and 0.08 y-1 respectively. Due to the calculated exploitation rate (0.14) in the period of study, the stock of A. nibe in the Oman Sea was not under the pressure. The probability of capture (L50) was determined 33cm in total length, was less than the reported LM50 (35 cm) of A. nibe in the Oman Sea, and it was found that the used gear mesh size was not suitable for A. nibe fishery.