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... In conclusion, Sri Lanka has a remarkable diversity of sharks and rays and even some potentially undescribed species (De Silva, 2014;Fernando et al., 2019). Such diversity is essential for a healthy ecosystem and one that benefits fishers and other stakeholders who depend upon it for their survival. ...
• All five species of sawfishes (family Pristidae) are amongst the most threatened marine fishes in the world, with steep population declines and local extinctions documented across their ranges.
• Sawfishes have featured in Sri Lankan species checklists since 1889. However, landing records are extremely rare and little information is available on their status, diversity, and recent occurrences.
• Interviews were conducted with 300 fishers and 10 fish traders. Only 39% of fishers (n = 118) could identify sawfishes, 37% had seen sawfishes (although half not since 1992), and only 10.7% had ever caught one. No respondents under 30 years could identify sawfishes. Older respondents (>50 years) were more likely to have caught sawfishes and reported seeing them frequently until 30 years ago, while younger respondents had only seen them at landing sites and, at most, once or twice in their life. Only 10 respondents had seen a sawfish in the last decade, suggesting that sawfishes were relatively abundant in the past but that populations have drastically declined.
• Of the 32 respondents who had caught sawfishes, 30 reported declining numbers and attributed it to fishing pressure. These steep declines coincide with the time of increased fishing effort, the development of the aquaculture industry, and resulting degradation of coastal habitats in the 1980–1990s.
• Overall, sawfishes had little cultural significance although fishers had specific names for the different species occurring here and rostra were sometimes donated to Catholic churches for ‘good luck’. Landed sawfishes were primarily sold for meat and traders appeared unaware of the high value of fins.
• It is likely that sawfishes are now functionally extinct as a component of coastal ecosystems in Sri Lanka. Immediate action including species-specific legislation and critical habitat protection is urgently needed to provide remaining sawfishes and other sharks and rays with a fighting chance.
Identities of elasmobranchs from Sri Lanka encountered during collections conducted in an intensive nine-day survey of fish markets and landing sites at 11 localities in the North Western, Northern, and Eastern Provinces in March of 2018 were assessed. In total, 111 specimens representing 34 elasmobranch species were examined. Sequence data for the NADH2 gene were generated for all specimens. Independent Neighbor-Joining analyses, which included data for related taxa, were conducted for 25 subgroups of elasmobranchs to help confirm specific identifications. Five of the 34 species encountered are likely new to science. These consist of one species each of the batoid genera Brevitrygon, Narcine, and Torpedo, and the selachian genera Centrophorus, and Chiloscyllium. The specific identities of 12 species previously known to occur in Sri Lanka are updated to conform to current taxonomy; four of these (Gymnura cf. poecilura 2, Carcharhinus cf. limbatus, Echinorhinus sp. 1, and Iago cf. omanensis 1) represent what appear to be undescribed species reported previously from other localities. Three species (Maculabatis arabica, Acroteriobatus variegatus, and Centroscymnus owstonii) are reported from Sri Lanka for the first time; the latter species also represents the first documented record of this genus and family for the island nation. One of the two specimens on which the recent description of the new species of Planonasus indicus was based was also collected as part of this survey. Although some of the species confirmed to occur in Sri Lanka have also been found in India, others were previously known only from the Persian Gulf, Gulf of Oman, or localities in Southeast Asia. The high amount of novelty discovered as a result of a survey of such short duration emphasizes the importance of more intensive survey efforts in this region now that the civil unrest that precluded such work for nearly three decades has come to an end.
This report provides an overview of the con- servation status of chondrichthyans (sharks, rays, and chimaeras) in the Arabian Seas Region (ASR) and describes the results of a regional Red List workshop held in Abu Dhabi, United Arab Emirates, in February 2017. It identies those species that are threatened with extinction at the regional level, so that appropriate conservation action can be taken to improve their status. A regional overview of chondrichthyan fisheries, management and conservation is also presented.
Although 184 species of sharks, rays, and chimaeras occur in the ASR, only the confirmed 153 species were considered in this project.The geographic scope encompasses the Red Sea, Gulf of Aden, Arabian Sea, Sea of Oman and the Gulf.This includes the Exclusive Economic Zone (EEZ) of 20 countries bordering three Large Marine Ecosystems (i.e., the Arabian Sea, Red Sea, and Somali Current). This region comprises some of the largest and most important chondrichthyan fishing nations in the world, including India and Pakistan.
All assessments followed the IUCN Red List Categories and Criteria Version 3.1 and the Guidelines for Application of the IUCN Red List Criteria at Regional and National Levels Version 4.0. During the workshop, a network of leading international and regional experts on chondrichthyans and fisheries compiled data and knowledge to prepare 30 global (endemic species) and 123 regional species assessments. All assessments were agreed on by consensus at the workshop and any changes to statuses during the review process were agreed on through email correspondence with lead assessors and contributors prior to their submission to the IUCN Red List of Threatened Species and inclusion in this report.
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