DNA-based species identification of shark fins traded in thai markets

Shark fins are among the most highly prized seafood products in the world with massive consumption in Asia over the past several decades. The demand for shark fins is a major driver of the enormous population declines of elasmobranchs that are generally vulnerable to overexploitation. This study aims to better understand the species composition of shark fin products in Thailand and their conservation statuses by using DNA-based species identification. Various types and sizes of shark fins were collected from 4 locations in Thailand. DNA barcoding method based on a fragment of the cytochrome c oxidase subunit I (COI) gene was applied to species identification. Fins from at least 15 shark species were found from Thailand's markets. The spottail shark (Carcharhinus sorrah) and the night shark (Carcharhinus signatus) were the two dominant species presented in this study. 34% of identifiable samples are the species that have not been record in this region. 62% of species detected from the fin samples are categorized under the threatened categories of IUCN Red List. Species composition reported in shark fin products potentially helps indicate the appropriate conservation action and increases awareness from monitoring the trade in elasmobranch products.

Automated summary

This study examined the species composition and conservation statuses of shark fin products in Thailand using DNA-based species identification. At least 15 shark species were found in Thailand's markets, with the spottail shark and the night shark being the dominant species. There were 34% of identifiable samples that were previously unrecorded in the region, and 62% of species detected from the fins were classified as threatened on the IUCN Red List. The species composition of shark fin products can help guide conservation actions and raise awareness about the trade in elasmobranch products.