Das Sumi Rani, Pandit Debasish, Harun-Al-Rashid Ahmed, Tasnim Nishat, Kunda Mrityunjoy
Department of Aquatic Resource Management, Sylhet Agricultural University, Sylhet, 3100, Bangladesh.
Heliyon. 2022 Jul 8;8(7):e09903. doi: 10.1016/j.heliyon.2022.e09903. eCollection 2022 Jul.
Brush pile (), a fish aggregating device, has been widely used in the Shari-Goyain River since 2003 to congregate fish for easier catch. is usually used during the winter season when the water depth decreases. Hence, this experiment was conducted from November 2018 to March 2019 on fishing to investigate its status and impacts on fisheries resources of the Shari-Goyain River in the Sylhet district of Bangladesh. The study was based on the hypothesis that fishing might have detrimental impacts to fish biodiversity and production. Data were obtained through a questionnaire-based survey, personal interviews, catch assessment (CA), focus group discussions, and key informant interviews. A total of 54 species were documented, including two exotic fish species (tilapia and common carp) and 3 species of prawn during harvesting of the . The catch per unit effort (CPUE) (kg/gear/ha/person/hour) was the highest in December (1.13 ± 0.37), followed by November (1.06 ± 0.40), January (0.80 ± 0.25), February (0.71 ± 0.23), and March (0.52 ± 0.21). The catch per unit area (CPUA) (kg/ha) was the highest in November (264.66 ± 18.21), followed by December (205.05 ± 27.77), January (175.02 ± 76.04), February (147.73 ± 52.11), and March (102.08 ± 41.04) where significant differences (p < 0.05) among the months were observed. Average catch per in a month ranged from 41.09 ± 16.11 to 12.42 ± 5.89 kg, with a mean of 24.29 ± 11.08 kg, and a significant decrease in average catch was observed with the progression of months. The most species richness was noticed in December (38), followed by November (35), January (34), February (28), and March (25). Siluriformes (39.123%) was the most dominant order, followed by Cypriniformes (33.956%), Decapoda (14.661%), and Ovalentaria (3.278%). According to the CA and respondents' perception, indiscriminate harvesting of fish by fishing can be a cause of fish biodiversity loss as it reduces open water catches, total production, and disturbs the ecosystem. From the research findings, it is suggested that fishing should be stopped for sustainable management and conservation of fisheries resources in the Shari-Goyain River. Research on the effects of fishing should be conducted in other open waters of Bangladesh where this type of fishing is common.
树枝堆（一种聚鱼装置）自2003年以来在沙里 - 戈亚因河被广泛使用，用于聚集鱼类以便更轻松地捕获。通常在冬季水深下降时使用。因此，本实验于2018年11月至2019年3月针对树枝堆捕鱼进行，以调查其现状以及对孟加拉国锡尔赫特地区沙里 - 戈亚因河渔业资源的影响。该研究基于这样的假设，即树枝堆捕鱼可能对鱼类生物多样性和产量产生不利影响。数据通过问卷调查、个人访谈、渔获量评估（CA）、焦点小组讨论和关键信息提供者访谈获得。在树枝堆捕鱼收获期间，共记录了54个物种，包括两种外来鱼类（罗非鱼和鲤鱼）以及3种虾类。单位努力渔获量（CPUE）（千克/渔具/公顷/人/小时）在12月最高（1.13±0.37），其次是11月（1.06±0.40）、1月（0.80±0.25）、2月（0.71±0.23）和3月（0.52±0.21）。单位面积渔获量（CPUA）（千克/公顷）在11月最高（264.66±18.21），其次是12月（205.05±27.77）、1月（175.02±76.04）、2月（147.73±52.11）和3月（102.08±41.04），各月份之间存在显著差异（p<0.05）。每月每个树枝堆的平均渔获量在41.09±16.11至12.42±5.89千克之间，平均为24.29±11.08千克，并且随着月份的推进，平均渔获量显著下降。物种丰富度在12月最高（38种），其次是11月（35种）、1月（34种）、2月（28种）和3月（25种）。鲇形目（39.123%）是最主要的目，其次是鲤形目（33.956%）、十足目（14.661%）和鲈形目（3.278%）。根据渔获量评估和受访者的看法，树枝堆捕鱼中对鱼类的滥捕可能是鱼类生物多样性丧失的一个原因，因为它减少了开阔水域的渔获量、总产量并扰乱了生态系统。从研究结果来看，建议停止树枝堆捕鱼，以实现沙里 - 戈亚因河渔业资源的可持续管理和保护。应在孟加拉国其他这种捕鱼方式常见的开阔水域开展关于树枝堆捕鱼影响的研究。
