Outbreeding Depression In Pink Salmon: Effects of Hybridization Between Seasonally Distinct Pink Salmon Subpopulations: Phase 3
Investigators
School of Fisheries and Ocean Sciences, University of Alaska Fairbanks
School of Fisheries and Ocean Sciences, University of Alaska Fairbanks
School of Fisheries and Ocean Sciences, University of Alaska Fairbanks
University of Alaska Fairbanks
Students
- Jesse Echave, MS program
- Christopher V Manhard, PhD program
Synopsis
This study continues research that began in 2004 to examine whether interbreeding between hatchery and wild salmon significantly diminishes the average genetic fitness of wild salmon populations.
Through purposeful or accidental processes, hatchery-bred salmon can mate with wild salmon, resulting in maladapted offspring, loss of genetic fitness, and depressed economic value of wild salmon stocks. In phase three of this project, researchers continue studying the effects of outbreeding and its implications on local adaptation in salmon. Specifically, they are attempting to detect effects of outbreeding of hybrids between seasonally distinct pink salmon populations in Auke Creek near Juneau, Alaska.
Overview
The issue
Does interbreeding between hatchery and wild salmon significantly diminish genetic fitness of wild salmon populations?
Why is this an Alaska Sea Grant project?
Fisheries is theme 3 within the Alaska Sea Grant Strategic Plan 2004–2010. Goal 1 under this theme seeks to develop management strategies that incorporate ecosystem approaches to fishery harvest balanced with conservation of Alaska's living resources from marine, estuarine, and coastal watershed environments.
Results
What researchers learned
In the process of preparing the Molecular Ecology paper, we conducted stock-recruit analyses on total Auke Creek return and emigration. Unsurprisingly, we detected a density-dependent relationship between returning adults and emigrant fry. Surprisingly, we also detected a density-dependent relationship between emigrant fry and the numbers of adults they produce. Chris Manhard is pursuing those observations by incorporating multiple likely pertinent environmental variables in the analyses.
Research outcomes
Publications
Gharrett, A.J. 2014. What does genetics have to do with it? Alaska Sea Grant College Program, University of Alaska Fairbanks, AN-18, Fairbanks.
This electronic publication contributes to understanding of the biology of fishes, by clarifying the role genetics plays in conservation and management of fisheries. The mechanisms of inheritance, and the changes in genetic instructions that occur during evolution, are the basis of all aspects of fish biology. The audience is fish culturists, fishery managers, fishermen, and the public.
Gharrett, A.J., J. Joyce, and W.W. Smoker. 2013. Fine-scale temporal adaptation within a salmonid population: mechanism and consequences. Molecular Ecology 22:4457-4469. https://doi.org/10.1111/mec.12400
Manhard, C.V. 2012. A test of local adaptation in seasonally separate subpopulations of pink salmon (Oncorhynchus gorbuscha). Master's thesis, University of Alaska Fairbanks, SGT-12-10, 48 pp.
