Department of Zoology, University of Dhaka, Dhaka, Bangladesh.
Department of Zoology, University of Oxford, Oxford, United Kingdom.
PLoS One. 2019 Sep 25;14(9):e0222273. doi: 10.1371/journal.pone.0222273. eCollection 2019.
Trade involving elasmobranch products in Bangladesh is a four-decade-long practice in large scale and there is little understanding of its impact on species composition, population, and subsequent conservation. Capacity for monitoring and identification is lacking in landing and shark processing centres. A rapid survey and collection of tissue samples were performed in three landings and nine shark processing centres between 2016 and 2017 in the south-eastern coastal region of Bangladesh. Sequencing for a 707-bp fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene was used to assess the taxonomic status and species composition from 71 elasmobranch tissue samples collected from the shark processing centre only. Good quality COI sequences were obtained for 34 specimens representing 21 species-the majority of which are threatened with extinction. A total of ten species of sharks (Carcharhinus brevipinna, C. amboinensis, C. leucas, C. sorrah, C. amblyrhynchoides, Chiloscyllium burmensis, Galeocerdo cuvier, Rhincodon typus, Scoliodon laticaudus, and Sphyrna lewini), eleven species of rays (Aetomylaeus maculatus, Gymnura poecilura, Mobula mobular, M. kuhlii, Neotrygon indica, Pateobatis uarnacoides, Rhinoptera javanica, and R. jayakari), including three species of guitarfish (Glaucostegus granulatus, G. obtusus, and G. typus), were identified. Four species (14.7% of samples) were found to be listed in the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in Appendix II. Sixteen species (59% of the specimens) were threatened with extinction according to IUCN Red List, whereas 41% were data deficient or not assessed. The results have important implications for the management of regional fisheries and the conservation of elasmobranchs as they 1) represent a preliminary understanding of elasmobranch diversity in trade; 2) depict a lack of awareness and monitoring; and 3) demonstrate a need for urgent monitoring and regulation of elasmobranch trade in Bangladesh.
在孟加拉国，涉及鲨鱼产品的贸易已经有四十多年的历史，规模庞大，但人们对其对物种组成、种群数量以及随后的保护的影响知之甚少。在登陆点和鲨鱼加工中心缺乏监测和识别能力。在 2016 年至 2017 年间，在孟加拉国东南部沿海地区的三个登陆点和九个鲨鱼加工中心进行了快速调查和组织样本采集。从仅从鲨鱼加工中心采集的 71 个鲨鱼组织样本中，通过对线粒体细胞色素 c 氧化酶亚基 I（COI）基因的 707 个碱基片段进行测序，评估了分类地位和物种组成。从 34 个标本中获得了高质量的 COI 序列，这些标本代表了 21 个物种，其中大多数物种都面临灭绝的威胁。总共鉴定出 10 种鲨鱼（短鳍真鲨、湾鳄、白鳍鲨、柠檬鲨、路氏双髻鲨、孟加拉叶鳍鲶、无沟双髻鲨、尖吻魟、斑纹须鲨和柠檬鲨）、11 种鳐鱼（斑点星鲨、波纹长尾鲨、日本蝠鲼、灰星鲨、印度无沟双髻鲨、乌翅真鲨、日本喙吻鲨和小眼真鲨），包括三种魟鱼（波纹真鲨、尖犁头鳐和犁头鳐）。其中 4 种（样本的 14.7%）被发现列入《濒危野生动植物种国际贸易公约》（CITES）附录 II。根据 IUCN 红色名录，有 16 种（标本的 59%）鲨鱼面临灭绝威胁，而 41%的数据不足或未评估。这些结果对区域渔业管理和鲨鱼保护具有重要意义，因为它们：1）代表了对贸易中鲨鱼多样性的初步了解；2）描绘了缺乏意识和监测；3）表明孟加拉国迫切需要对鲨鱼贸易进行监测和监管。
