Genetic stock composition of loggerhead turtles Caretta caretta bycaught in the pelagic waters of the North Atlantic

Endangered Species Research

Erin L. LaCasella¹  Lesley Stokes¹  Sheryan P. Epperly¹  Michael P. Jensen¹  Peter H. Dutton¹ 

关键词: Mitochondrial DNA;    Mixed stock analysis;    Fisheries;    Bycatch;    Northeast Distant Longline Fishery;   

DOI  :  10.3354/esr00535

学科分类：动物科学

来源: Inter-Research

【 摘 要 】

ABSTRACT: Sea turtle populations disperse widely across oceans and migrate between terrestrial nesting habitat and distant feeding and developmental habitats. Understanding population stock structure is important for accurately assessing threats such as mortality from fishery bycatch and for defining specific demographic units of conservation concern. We compared 775 bp mtDNA control region haplotypes from 389 juvenile loggerhead turtles sampled as bycatch in the US pelagic longline fishery in the western North Atlantic Northeast Distant (NED) region to haplotype frequencies observed in 23 genetically distinct nesting stocks representing the 4 distinct population segments (DPSs) that have been identified throughout the Atlantic Ocean and Mediterranean Sea. We used Bayesian mixed-stock analysis to produce stock composition estimates for juvenile loggerhead turtles that use pelagic habitat in the central North Atlantic. We found that nearly all of the loggerheads caught in NED waters belonged to the Northwest Atlantic DPS (mean = 99.2%), with the majority coming from the large eastern Florida rookeries (mean = 84.0%). We also detected contributions from the western Florida rookeries (mean = 11.7%) and Mexico (mean = 3.5%) but found little evidence of contributions from the rookeries of the South Atlantic, Northeast Atlantic, or Mediterranean DPSs. These results will help improve specific threat assessments and are relevant to ongoing development of conservation plans that are aligned to the recent DPS listings for loggerheads.

【 授权许可】

Unknown