Species richness, genetic diversity and preliminary population structure of common snappers and groupers in aruban waters, estimated through dna barcoding

Student Report

Overfishing is a great threat to marine ecosystems and the people who depend on them. Even artisanal fishing of high intensity can lead to reduction of fish biomass and loss of coral cover. Aruba is a Caribbean island highly dependent on its marine ecosystem for its tourism industry, yet there is little to no published data on the current state of its fish stocks. Here, we use DNA sequencing of the cytochrome oxidase I gene to identify the species of snappers and groupers commonly caught by local artisanal fishermen, and research preliminary genetic information for these species in Aruban waters, including genetic identification, genetic diversity and population structure. Most fish caught were above maturity length (Lm), but all fish identified as Lutjanus vivanus were not. One of the groupers sampled was identified as Mycteroperca xenarcha, a species that has only been reported in the Pacific Ocean; its possible presence in the Atlantic must be researched further. We found significant population structure for Lutjanus synagris between Brazil and Aruba, Belize, Colombia, Florida and Mexico. This contradicts the results of previous studies, highlighting the need for more research and sampling around the Caribbean and Atlantic. Finally, the most commonly caught grouper in Aruba is Hyporthodus flavolimbatus, a vulnerable species of which little is known, but that shows a high level of local genetic diversity. Keywords Population structure, genetic diversity, fisheries, cytochrome oxidase, barcode gene, haplotype