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- 2017
Some Biological Aspects and Stock Status of Goldlined Seabream Rhabdosargus sarba (Forssk?l, 1775) from the Arabian Gulf of the United Arab EmiratesKeywords: Biological Aspects, Stock Status, Rhabdosargus Sarba, Mortality Rate, Arabian Gulf Abstract: Evaluation of Rhabdosargus sarba caught from South Arabian Gulf of the United Arab Emirates was investigated using a combination of size frequency and biological data. Forked length ranged between 14.0 and 39.0cm. Length-weight relationship for combined sexes of R. sarba was estimated as W=0.0338*L2.7807. The spawning season of R. sarba was over a limit time period from November to February and the peaks were in January and February for males and females respectively. The overall sex ratio throughout the study period was 1:1.4 males to females, which was not significantly different from 1:1. The size and age at 50% sexual maturity was 22.01cm FL and 2.39years. The FiSAT II software was used to perform the estimate of growth, mortality and exploitation rate. Parameter values of asymptotic length L∞ and growth coefficient K were 41.94cm FL and 0.25y -1 respectively. Age at length zero to was estimated by substituting the asymptotic length and growth coefficient in Pauly’s equation. Instantaneous rate of total and natural mortalities were estimated as 1.09, 0.66 y -1 respectively. The length at first capture was obtained as 19.51cm that was smaller than the length at first sexual maturity. The rate of fishing mortality (F=0.43y -1) is higher than the optimum level (F opt =0.33y -1) and was close to limit (F limit =0.44yr -1) biological reference point, indicated that the resource is slightly over-exploited. Results also indicated that the reduction of current level of fishing mortality to optimum level will lead to reduction of exploitation rate by 23.08%.
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