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AFSC/ABL: Southeast and Prince William Sound, Alaska Herring Microsatellite data,
2007-2008
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Herring is one of the most energy-rich fish in the Alaskan ecosystem, and when populations
struggle over time, such as the Lynn Canal population, there is management concern.
Prior to 1983, Lynn Canal herring supported a productive sac roe fishery, a bait fishery,
and a winter food and bait fishery. All commercial fisheries were closed in 1983
and remain so today. The purpose of this study was to examine the genetic structure
of Lynn Canal herring and determine if it was discrete from other collections in southeast
Alaska. We used microsatellite DNA to examine both spawning and non-spawning aggregates
(collected in two consecutive years) in Lynn Canal, and compared them to two Southeast
Alaska populations: Prince of Wales Island (southernmost waters) and Sitka Sound
on Baranof Island (outer-coast). In addition we examined two collections from Prince
William Sound (approx. 850 km NW) as a means to compare extent of divergence over
large tracts of unsuitable spawning habitat. Because the geographic location of Lynn
Canal is somewhat isolated and schools are known to over-winter in the area, we hypothesized
that Lynn Canal herring experience reduced gene flow. The results of our study showed
allele frequencies from 16 loci were highly similar across all collections, including
the distant Prince William Sound. This investigation concurs with previous studies
that there is a large amount of movement among herring in the Gulf of Alaska. We
conclude that Lynn Canal herring are part of a meta-population that is possibly Gulf
wide or larger.
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