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In this research, the catch trends and population characteristics of seven species of tuna (Thunnus albacares, Katsuwonus pelamis, Thunnus tonggol, Euthynnus affinis and Auxis thazard ) and seer fish or tuna-like fish (Scomberomorus commerson and Scomberomorus guttatus) were estimated by collecting information from the catch unloading areas in the southern coast of the country. In this project, in 2022-3, a total of twenty-eight thousand fish (27,910) were subjected to biometrics in the research stations. The growth indices for these species (Yellowfin tuna = YFT, Skipjack tuna = SKJ, longtail tuna= LOT, Kawakawa= KAW and Frigate tuna= FRI, and narrow-barred Spanish mackerel= COM and Indo-Pacific king mackerel=GUM) are 175, 92, 132, 90, 54, 173, and 83 cm, respectively, and the annual growth rate is 0.55. , 0.68, 0.39, 0.49, 0.49, 0.52 and 0.5, annual natural mortality 0.49, 0.7, 0.61, 0.55, 0.66, 47. 0 and 0.58, the total annual mortality is 2.41, 1.07, 1.49, 1.58, 1.68, 1.42 and 2.83 and the annual utilization rate is 0.8, 0.35. 0.59, 0.65, 0.61, 0.67 and 0.8 were calculated. The ratio of current fishing mortality to fishing mortality of maximum sustainable yield (F/FMSY) for these species is 0.92, 0.82, 0.99, 1.16, 0.95, 1.55 and 0.69 and the ratio of current biomass to maximum sustainable product biomass (B/BMSY) showed 0.95, 1.41, 0.96, 0.85, 1.38, 0.9 and 1.35, respectively. The percentage of samples below the maturity length of YFT, SKJ, LOT, KAW, FRI, COM and GUM species in this study are 42%, 57%, 60%, 25%, 15%, 45% and 24% were obtained, respectively. The recommended net length based on the optimal catch length for the species of T.albacares, K. pelamis, T. tonggol, E. affinis, A.thazard S. commerson , S. guttatus species is approximately 19 cm, 13 cm, 17 cm, 12 cm, 7 cm, 15 cm and 10 cm were obtained, respectively. This research shows that based on the LBSPR index, YFT species has a poor stock status, SKJ species has an average stock status, LOT species has a poor reserve status, KAW species has an average stock status, FRI species has a good stock status, COM species has a poor stock status, and GUM species has an average stock status. Also, it seems that the amount of annual harvest from Yellowfin tuna and narrow-barred Spanish mackerel has reached its optimal limit, and measures should be taken to reduce the amount of catch and fishing effort.
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