Coastal sharks supply the global shark fin trade.

Kyle S Van Houtan,Stephen R Palumbi,Tyler O Gagné,Kisei R Tanaka,Salvador J Jorgensen,Gabriel Reygondeau

doi:10.1098/rsbl.2020.0609

Abstract

Progress in global shark conservation has been limited by constraints to understanding the species composition and geographic origins of the shark fin trade. Previous assessments that relied on earlier genetic techniques and official trade records focused on abundant pelagic species traded between Europe and Asia. Here, we combine recent advances in DNA barcoding and species distribution modelling to identify the species and source the geographic origin of fins sold at market. Derived models of species environmental niches indicated that shark fishing effort is concentrated within Exclusive Economic Zones, mostly in coastal Australia, Indonesia, the United States, Brazil, Mexico and Japan. By coupling two distinct tools, barcoding and niche modelling, our results provide new insights for monitoring and enforcement. They suggest stronger local controls of coastal fishing may help regulate the unsustainable global trade in shark fins.

Highlights

Scientists have long sought diagnostic tools to improve monitoring biodiversity in wild ecosystems and in markets [1,2] at a scale that matches their occurrence and exploitation [3,4]. Such tools could be vital for assessing the wildlife trade, where the species and geographic origin are often difficult to diagnose from traded products [5]
Published studies [13,14,15,16] used cytochrome oxidase (COI) sequencing to provide robust species identifications for 5327 shark fins sampled at markets in Brazil, Canada, China and the United 2 States
Our analyses suggest most harvested shark fins originate within Exclusive Economic Zones (EEZs) rather than in high-seas regions, counter to previous assessments [3]

Summary

Introduction

Scientists have long sought diagnostic tools to improve monitoring biodiversity in wild ecosystems and in markets [1,2] at a scale that matches their occurrence and exploitation [3,4]. For the shark fin trade, coupling the two approaches into a single analysis may help narrow a broad problem by describing the most probable shark fishing locations, potentially revealing geographic, which will improve monitoring and conservation. Four recent studies [13,14,15,16] revealed the source species of over 5000 individual shark fins from markets in Hong Kong, Vancouver, San Francisco and northern Brazil.

Results

Conclusion