Population structure of sablefish Anoplopoma fimbria using genetic variability and geometric morphometric analysis

Population structure of the sablefish (Anoplopoma fimbria) in the northeastern Pacific Ocean was determined using three approaches: geometric morphometrics (14 landmarks), mitochondrial DNA (fragment of COI gene), and nuclear DNA (four microsatellite loci). Samples came from the Bering Sea, Gulf of Alaska, offshore Oregon, and offshore the mid-Baja California Peninsula (at San Quintin). Differences in body shape were grouped in the samples from the north (Bering Sea and Gulf of Alaska). A slight but significant population structure was also observed in allele frequencies of microsatellites, FST values, amova, and Bayesian individual assignment tests; however, analyses of population structure using mtDNA did not reveal any population differentiation. Differences in population structure detected by distinct approaches, in addition to the moderately high haplotype diversity and low nucleotide diversity of the COI fragment, suggest recent and developing population differentiation in the sablefish.