Genetic Structure of Auke Creek Pink Salmon
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Jerry Taylor
Auke Bay Laboratories
Alaska Fisheries Science Center, NOAA Fisheries
Ted Stevens Marine Research Institute
17109 Pt Lena Loop Rd
Juneau AK 99801
(907) 789-6040
Jerry.Taylor@noaa.gov
More than 20 years of studying the genetics of natural runs of pink
salmon in Auke Creek has provided
insight into the role of genetics in the success of anadromous
populations. The studies are a result of a cooperative program between
the University of Alaska
Fairbanks (UAF) School of Fisheries and Ocean Sciences, (SFOS)
and the National Marine Fisheries Service Auke Bay Laboratory. The
program began in 1979 with a genetic marking project. Returning
genetically-marked fish showed that Auke Creek pink salmon had strong
genetic structure, which is related to return timing and which has
persisted in subsequent generations. Moreover, population genetic
studies of population structure in Auke Creek demonstrated significant
effects of return timing on genetic frequencies in both even- and
odd-year runs.
Subsequent heritability studies also demonstrated genetic influences
on timing and, consequently, population structure. Breeding
studies that examined migration timing as a genetic trait showed that
variation in timing of return had a basis in additive genetic variance.
Studies of development rate in early- and late-returning fish showed
that development rates differed between the run segments in ways that
can be generally explained as adaptation to environmental conditions.
In addition, analysis of family sizes of pink salmon returning to Auke
Creek indicated a genetic effect on marine survival that is more
accentuated in large returns than small returns. The implications are
that a small portion of the population contributes disproportionately to
the next generation, and, as a consequence of interannual environmental
variation, the more successful portion varies unpredictably from
generation to generation. Maintenance of genetic variation is a key to
the long-term success of a population. However, studies at Auke
Creek with inter-brood year hybrids suggest that outbreeding depression
may also occur. Clearly the quality of the variation is important.
For more information on pink salmon genetics studies at Auke Creek,
please contact Dr. A.J.Gharrett, UAF
(ffajg@uaf.edu)
or Dr. William Smoker, UAF (ffwws@uaf.edu).
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