Using DNA barcoding to describe the diversity of sharks found in the fishery in Puerto Rico

For decades, the worldwide population of sharks has been drastically decreased due to illegal fishing. In healthy marine ecosystems, these organisms are considered top predators since their elimination would result in a negative effect in the trophic chain, where an increase in mesopredators would be observed. This would generate a reduction in herbivorous fish, and at the same time give way to an increase in macroalgae cover on coral reefs. Given that to this day, there is little known about distribution, ecology, diversity, nurseries, and of shark fishing in Puerto Rico, it is of upmost importance to carry out a study like that described herein. The prime objective is to document the different species of sharks found in the fisheries around the island using DNA barcoding. In addition, we have observed that fishers lack the knowledge of the ecological importance of these animals, and what species are threatened and/or being protected by local, federal and international law. To address this question, shark tissue has been collected since June 2017 through April 2019 from local fishers and markets. Upon examination with DNA barcoding, preliminary data of this project establishes that at least seventeen species of shark are captured in the coasts of Puerto Rico, where approximately fifteen are consumed and two are considered too small for their sale (ie. Etmopterus sp.). Some of these species are listed on the IUCN Red List as species in danger, vulnerable or at risk of a decrease in population. The purpose of this study is to investigate the representation of sharks in the commercial and recreational fishery of Puerto Rico. We hypothesize that DNA barcoding will provide accurate depiction of the sharks represented in the fishery. The results of the project will be presented to fisheries management and educating fishers to promote conservation efforts.