Genetic differentiation in blue shark, Prionace glauca, from the central Pacific Ocean, as inferred by mitochondrial cytochrome b region

Abstract

Six hundred and ninety-seven base pairs of cytochrome b gene of mtDNA was sequenced and analyzed for 78 blue shark Prionace glauca individuals from three sampled locations in the central Pacific Ocean (CPO). In total, three polymorphic sites were detected which defined four haplotypes. The haplotype diversity (h) ranged from 0.517 to 0.768, and nucleotide diversity (π) was between 0.0007 and 0.0011. Analysis of molecular variance indicated a non-significant differentiation among subpopulations. Furthermore, pairwise F_ST score analysis revealed a non-significant differentiation among three sampled regions. Generally, low genetic differences were found between different geographic locations in the CPO. This study suggests a single panmictic population of P. glauca in the CPO.

Keywords:

• Blue shark Prionace glauca
• central Pacific Ocean
• cytochrome b gene
• genetic differentiation

Acknowledgements

We would like to express our thanks to the Professor Cody Szuwalski from the University of California Santa Barbara and the reviewers who made comments for assistance in improving the paper.

Declaration of interest

This work was supported by the China National Fisheries Observer Program (08-54) and Collaborative Innovation Center for Distant water Fisheries (B2-5004-13-0101). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the article.

Notes

¹“‘overfished’ Overfished” means that the biomass is beneath BMSY (Hilborn & Stokes., 2010).

²“‘overfishing’ Overfishing” means that the fishing mortality rate is higher than FMSY (Cunningham & Whitmarsh, 1981).