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- 2018
Mortalities and Exploitation Rate of Mediterranean Horse Mackerel, Trachurus mediterraneus (Steindachner, 1868) in the Central Black SeaKeywords: ?stavrit,Trachurus mediterraneus,boy,a??rl?k,s?mürülme,Karadeniz Abstract: This study provides some actual information about length, weight, age, and mortality rates of Mediterranean horse mackerel ( Trachurus mediterraneus) population in the central Black Sea in order to detect whether fishing pressure or not. A total of 1467 specimens were monthly collected from commercial purse-seiners, which especially landed to Sinop fishing port between September 2016 and March 2017. A total of 109 otoliths were used for age reading. Total length and weight of T. mediterraneus specimens were ranged from 7.1 cm to 20.3 cm (average: 14.02±0.04 cm) and 3.2 g to 67.7 g (average: 23.8±0.19 g). The samples were grouped densely between 12 and 15 cm and about 84% of samples in this study were within the legal size. Length-weight relationship was calculated as W = 0.0067 × TL 3.0848 (r 2 = 0.94). Age groups of horse mackerel in the central Black Sea were between I and III. Mean lengths according to age groups were 9.9±0.36 cm, 14.1±0.11 cm and 16.7±0.13 cm, respectively. Also, von Bertalanffy Growth Parameters were L ∞ = 19.14±0.46 cm, K = 0.65 ±0.03, t 0 = -0.08±0.007 year. Mortalities (M, F and Z) and exploitation rate (E) of T. mediterraneus from the Central Black Sea were 0.84 year -1, 0.87 year -1, 1.712 year -1 and 0.51 year -1, respectively. The rates of exploitation and minimum landing size indicate that there is no overfishing on T. mediterraneus population in the area for the time being
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