Barcoding a glass eel migration: a snapshot of taxa migrating upstream in the Palu River, Central Sulawesi, Indonesia

Abstract

Eels of the genus Anguilla are high value food fish with a catadromous life cycle. As tropical anguillid glass eels migrate to freshwater in multi-species schools, effective management of these and other diadromous resources requires reliable data. Previous research using two morphological methods concluded that between three and five anguillid eels recruit to the Palu River in Central Sulawesi, Indonesia with interannual and seasonal variations in species composition, size structure, and co-migrating taxa. Some glass eels and other taxa could not be identified based on external morphology. To clarify the taxonomic uncertainty regarding species recruiting to the Palu River this study applied DNA barcoding using the Cytochrome Oxidase I (COI) mitochondrial DNA (mtDNA) molecular marker. Taxa identified from the first sampling of glass eels and other taxa recruiting in these mixed schools included three anguillid eels, five other fishes, two crustacea and one mollusc, presenting a snapshot of taxa migrating upstream in the Palu River. Current GenBank accessions did not enable species level identification of two fish larvae (families Eleotridae and Tetraroginae). The sequences will add to Indonesian accessions in the GenBank repository and inform resource management, including the use of environmental DNA (eDNA) methods for monitoring Indonesian anguillid eels.