Assessing species diversity of Coral Triangle artisanal fisheries: A DNA barcode reference library for the shore fishes retailed at Ambon harbor (Indonesia).

Gino Limmon,Frederik Rijoly,Nicolas Hubert,Frédéric Busson,Hadi Dahruddin,Dirk Steinke,Jesaya Patikawa,Erwan Delrieu-Trottin

doi:10.1002/ece3.6128

Abstract

The Coral Triangle (CT), a region spanning across Indonesia and Philippines, is home to about 4,350 marine fish species and is among the world's most emblematic regions in terms of conservation. Threatened by overfishing and oceans warming, the CT fisheries have faced drastic declines over the last decades. Usually monitored through a biomass‐based approach, fisheries trends have rarely been characterized at the species level due to the high number of taxa involved and the difficulty to accurately and routinely identify individuals to the species level. Biomass, however, is a poor proxy of species richness, and automated methods of species identification are required to move beyond biomass‐based approaches. Recent meta‐analyses have demonstrated that species richness peaks at intermediary levels of biomass. Consequently, preserving biomass is not equal to preserving biodiversity. We present the results of a survey to estimate the shore fish diversity retailed at the harbor of Ambon Island, an island located at the center of the CT that display exceptionally high biomass despite high levels of threat, while building a DNA barcode reference library of CT shore fishes targeted by artisanal fisheries. We sampled 1,187 specimens and successfully barcoded 696 of the 760 selected specimens that represent 202 species. Our results show that DNA barcodes were effective in capturing species boundaries for 96% of the species examined, which opens new perspectives for the routine monitoring of the CT fisheries.

Highlights

Located at the boundary between the Indian and Pacific Ocean, the Coral Triangle (CT) is home to some 4,350 marine fish species (Froese & Pauly, 2014)
In order to determine the fish diversity harvested by artisanal fisheries in the CT, we set out to build a DNA barcode inventory of the shore fish species retailed at Ambon Island
By providing the first reference library available to date for commercial shore fishes of the CT, this study enables the DNA-based assignment of unknown individuals to known species

Summary

| INTRODUCTION

Located at the boundary between the Indian and Pacific Ocean, the Coral Triangle (CT) is home to some 4,350 marine fish species (Froese & Pauly, 2014). Biomass estimates are usually derived from fisheries statistics or underwater visual census through allometric length– weight relationships, further converted into units of mass per area, a proxy that only account for a fraction of the coral reef biodiversity This level of granularity and the increasing consumer demand for better food traceability requires reliable and routine species level identification of fish products. In order to determine the fish diversity harvested by artisanal fisheries in the CT, we set out to build a DNA barcode inventory of the shore fish species retailed at Ambon Island This approach accounts for potential cryptic diversity and helps to establish a sustainable resource for fisheries monitoring and food traceability. Ambon Island can serve as a model for artisanal fisheries in less perturbed parts of the CT, and the diversity of landed fish determined by our study is expected to provide valuable information on fisheries trends elsewhere

| MATERIALS AND METHODS

Findings

| DISCUSSION

| CONCLUSIONS