Population Dynamics and Exploitation Rate of Bronze Featherback (Notopterus notopterus, Pallas, 1769) for Sustainable Management in Huai Kho Reservoir, Na Chueak District, Maha Sarakham Province, Thailand

Abstract

The study on Bronze Featherback in Huai Kho Reservoir examined 273 specimens, with fork lengths ranging from 105 to 295mm and an average length of 185.80 ± 27.05mm. The fish exhibited a strong length-weight correlation, with an allometric coefficient (b) greater than 3.00, indicating a positive allometric growth. Growth parameters included an asymptotic length (L∞) of 309.75mm and a growth coefficient (K) of 0.10. Capture probabilities were 108.99 (L25%), 186.52 (L50%), and 191.44mm (L75%). Mortality rates were measured with a total mortality rate (Z) of 1.07 per year, natural mortality (M) at 0.22 per year, and fishing mortality (F) at 0.86 per year. Recruitment peaks occurred from June to August, and replacement rates were the highest from July to September. The current exploitation rate (E) of 0.80 exceeds the maximum sustainable rate (Emax) of 0.724. The total steady-state biomass was 10.57 tons. To promote sustainable management, it is recommended to regulate fishing gear and enforce a fishing ban during the spawning season.