Impact of fishing gear on fish biodiversity of Hakaluki haor in Bangladesh

Abstract

The present study was conducted to investigate the impact of fishing gears on fish biodiversity of Hakaluki haor for a period of 12 months. A total of 15 types of fishing gears such as nets, traps, hooks and lines, wounding gear and fish aggregating devices (FADs) were observed. The highest catch per unit effort (CPUE) was found in seine net (38.21 kg gear-1hour-1) during the month of January followed by push net and lift net. The lowest CPUE was 0.1135 kg gear-1hour-1 in traps during June to October while in hook and line CPUE was 0.2303 kg gear-1hour-1 during June to September. Major gears such as seine net, current jal, hand borshi, katha fishery, koi jal, khora jal, thela jal and different types of traps were used by the fishermen during the month of November to April. Catch composition of fish in the haor were Cypriniformes (36%), Siluriformes (23%), Perciformes (20%), Synbranchiformes (5%), Osteoglossiformes (4%), Clupeiformes (3%), Beloniformes (3%) Tetraodontiformes (2%) and Crustaceans (4%). On the basis of species composition, the dominant fish species were harvested by seine net, cast net, lift net, push net, chai, dori and hand borshi, which was considered as non-selective gears, while koi jal, current jal, and borshi were found as selective gears. This study revealed that the highest biomass of fish was caught in January while the lowest was recorded in July and August. Moreover, seine net and current jal were found to be harmful for most of the fish species in the Hakaluki haor.