Genetic variation between outer-coastal and fjord populations of Pacific herring (Clupea pallasii) in the eastern Gulf of Alaska

摘要

Pacific herring (Clupea pallasii) from the Gulf of Alaskaudwere screened for temporal and spatial genetic variation with 15 microsatellite loci. Thirteen collections were examined in this study: 11 from Southeast Alaska and 2 from Prince William Sound, Alaska. Although FST values were low, a neighbor-joining tree based on genetic distance, homogeneity, and FST values revealed that collectively, the Berners Bay and Lynn Canal (interior) collections were genetically distinct from Sitka Sound and Prince of Wales Island (outer-coastal) collections. Temporal genetic variation within regions (among three years of Berners Bayudspawners and between the two Sitka Sound spawners) was zero, whereas 0.05% was attributable to genetic variation between Berners Bay and Sitka Sound. This divergence may beudattributable to environmental differences between interior archipelago waters and outer-coast habitats, such as differences in temperature and salinity. Early spring collections of nonspawning Lynn Canal herring were nearly genetically identical to collections of spawning herring inudBerners Bay two months later—an indication that Berners Bay spawners over-winter in Lynn Canal. Southeast Alaskan herring (collectively) were significantly different from those in Prince William Sound. This study illustrates that adequate sample size is needed to detect variation in pelagic fish species with a large effective population size, and microsatellite markers may be useful in detectingudlow-level genetic divergence in Pacific herring in the Gulf of Alaska.