Ecological Study on the Population Dynamics of the Armatus Barb (Cyclocheilichthys armatus) in Huai Kho Reservoir, Northeastern Thailand

This research focused on understanding the population behavior of the Armatus Barb (Cyclocheilichthys armatus) in Huai Kho Reservoir, northeastern Thailand. Over the course of 2022, a total of 520 fish were sampled. Sampling was conducted monthly. Fish sizes varied from 90 to 205 millimeter in fork length, and weights ranged from 16 to 135 grams. The species showed a mean fork length of 128.42±17.05 millimeter and an average weight of 26.38±13.20 gram. Growth modeling indicated a maximum potential length of 194.25 millimeter, with a growth rate (K) of 0.44 per year. The species’ length–weight relationship (LWR) showed a strong correlation (W = 0.011343L¹.⁹⁴⁵²⁶; r² = 0.95). Estimated mortality rates included a natural mortality (M) of 0.65 year⁻¹, fishing mortality (F) of 1.18 year⁻¹, and total mortality (Z) of 1.83 year⁻¹. Recruitment occurred throughout the year, peaking between July and October, with a maximum in September (21.51%). The estimated length at first capture was 14.56 millimeter. The exploitation rate (E) was 0.65, surpassing the sustainability threshold of 0.50 and indicating considerable fishing pressure on the population. These findings suggest that the C. armatus population in the Huai Kho Reservoir is currently overexploited and experiencing overfishing. Therefore, management measures and harvesting regulations are urgently needed to ensure the sustainability of this species in the reservoir.