Smith BD, Khan A
P.O. Box 283 Arcata, California 95521, USA
Environ Manage. 1998 May;22(3):323-35. doi: 10.1007/s002679900108.
/ Ganges river dolphins (Platanista gangetica) are threatened in Bangladesh from the effects of dams, large embankment schemes, dredging, fisheries bycatch, directed hunting, and water pollution. Visual surveys of the section of the Jamuna River located between the divergence of the Old Brahmaputra River and the confluence of the Padma River and the section of the Kushiyara River located between the Bangladesh-India border and the confluence of the Korangi River recorded a sighting rate of 0.13 sightings/km (mean group size = 1.8 dolphins) and 0.08 sightings/km (mean group size = 3.8 dolphins), respectively. These sections of river were considered to be priority areas for investigation because several water development projects have already been constructed and more are planned for the areas. During the surveys we examined the remains of dolphins caught accidentally in plastic gillnets and observed fishermen catching the fish species Clupisoma garua using dolphin oil and body parts as a fish attractor. Additional studies are needed to assess the status of dolphins and effects of water development and fisheries bycatch. Feasibility studies should be conducted on designating dolphin/fish sanctuaries and creating artificial habitat or enhancing existing habitat in eddy countercurrent scour pools to mitigate deleterious impacts. The environmental requirements of river dolphins reflect the needs of productive and biotically diverse tropical rivers.KEY WORDS: Bangladesh; River dolphins; Water development; Platanista; Fisheries bycatch; Flood Action Plan; Dams; Embankments; Barrages
恒河江豚（Platanista gangetica）在孟加拉国受到大坝、大型堤坝工程、疏浚、渔业兼捕、直接捕猎和水污染的威胁。对位于旧布拉马普特拉河分流处与帕德玛河交汇处之间的贾木纳河段，以及位于孟加拉国-印度边境与科兰吉河交汇处之间的库希亚拉河段进行的目视调查显示，目击率分别为0.13次/公里（平均群体规模 = 1.8头江豚）和0.08次/公里（平均群体规模 = 3.8头江豚）。这些河段被视为优先调查区域，因为已经在这些区域建设了多个水利开发项目，并且还计划建设更多项目。在调查过程中，我们检查了被塑料刺网意外捕获的江豚残骸，并观察到渔民使用江豚油和身体部位作为鱼类诱饵来捕捞细纹鳠（Clupisoma garua）。需要进行更多研究来评估江豚的状况以及水利开发和渔业兼捕的影响。应开展可行性研究，以指定江豚/鱼类保护区，并在涡流逆流冲刷池中创建人工栖息地或改善现有栖息地，以减轻有害影响。江豚的环境需求反映了高产且生物多样的热带河流的需求。
孟加拉国；江豚；水利开发；恒河江豚属；渔业兼捕；防洪行动计划；大坝；堤坝；拦河坝
