Elasmobranchs are rapidly declining due to overfishing and bycatch, underlining the need for immediate protection. Critical baseline information on the diversity of targeted species is, however, often missing. Peru is a major country for shark fishery, an activity that has been under-regulated and poorly monitored, aggravated by the superficial taxonomic identifications at landing points across the country. Furthermore, most of the species landed by the shark fishery in Peru are listed as Vulnerable in the IUCN Red List. To assess the diversity of shark species targeted by fisheries in Peru we analyzed the variation of the cytochrome oxidase I (cox1) region of the mitochondrial DNA from 118 samples collected between 2004 and 2009, from six landing points. Our analysis revealed unambiguously that the 16 shark species classified by fishermen using meristic characters corresponded only to nine species. While some commonly landed species (e.g. Prionace glauca) were consistently correctly identified, for others species multiple inconsistent names were applied (e.g. Galeorhinus galeus). Our molecular characterization further allowed the identification of specimens with non-informative common names (i.e. "tiburon" = shark). In most cases the unknown specimens were Isurus oxyrinchus and P. glauca. Interestingly, all samples labeled as common thresher (Alopias vulpinus) were identified as pelagic thresher (Alopias pelagicus). Finally, one sample was equivocally identified as a dusky shark (Carcharhinus obscurus) and as a galapagos shark (Carcharhinus galapagensis) reinforcing the genetic similarity reported for these species. We generated a character-based identification library containing 26 of the 31 commercially important sharks landed in Peru and tested its performance as a species diagnostic. The library correctly identified 25 out of 28 barcodes tested, outperforming the distance-based approach. This is the first study sequencing barcodes of marine species in Peru and generated a genetic reference library of targeted shark species. We suggest that the molecular tools used are a quick and effective complement for the monitoring of the fishery of threatened shark species. A combined effort to obtain these data, by countries in the east Pacific region with an on-going shark fishery, would provide with the essential guiding information to promote the implementation of effective sustainable management plans.
Bibliographical noteFunding Information:
We thank ProDelphinus staff for sample collection and preparation, to Bryan Leon, Elsie Diaz, Bas van Schooten, Mariella Navarro and Ana C. Mendez for helping with sample analysis, and Silvia Planas and Dania Rodriguez from the Sequencing and Genotyping Facility (SGF) from University of Puerto Rico (UPRRP). SGF is supported by S.C.O.R.E Grant S06GM08102 & NIH I.N.B.R.E. grant P20RR16470 , UPRRP and UPR Central Administration . We are grateful to Rita Patricio for commenting on a previous version of this manuscript, and to anonymous reviewers and Editor for their insightful comments that greatly improved the final version of this manuscript. Samples were collected by Darwin Initiative for Sustainable Artisanal Fisheries in Peru, through University of Exeter. Funding for this study was granted to XVZ by Cleveland Metroparks (Scott Neotropical Fund) .
- Character-based identification
- Genetic analyses
- Southeast Pacific