Đánh giá khả năng chọn lọc theo mắt lưới hình thoi của nghề lưới đáy tại Cà Mau

Abstract

Abstract

The study utilized 3 net samples with cod-end mesh sizes of 18 mm, 20 mm, 24 mm and 04 mm mesh size of cover, to conduct 30 experimental hauls in Ngoc Hien district, Ca Mau province for data collection. The fishing process yielded 3,291 individual snakefish (Trachinocephalus myops) and 4,017 individual jinga shrimp (Metapenaeus affinis) for length analysis, and the Wileman selectivity method was employed to determine selective parameters of these two target species. The research results show that the fish length of snakefish at 50% capture probability (L₅₀) for net samples M1, M2, and M3 were 61.5 mm, 67.5 mm, and 71.9 mm, respectively, the corresponding lengths (L₅₀) for jinga shrimp were 50.7 mm, 61.2 mm, and 66.8 mm. The selection factor (SF) of the diamond chosen for snakefish was 3.42, and for Jinga shrimp, it was 2.82. The appropriate diamond mesh size for harvesting nakefish corresponding to L50 is 42 mm, and 36 mm for Jinga shrimp.

Key words: Ca Mau province, fishing gear selectivity, mesh size, stow net fishery.