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B. Types of genetic variation - include variation for qualitative 

 traits (under single gene control) and quantitative traits (controlled by 

 many genes, polygenic). Qualitative traits are described qualitatively 

 rather than by a measurement. Examples of qualitative traits are 

 polymorphic proteins detected by protein electrophoresis; variation in 

 these polymorphic proteins are often used for fish stock identification. 

 Quantitative traits vary in meristic or continuous fashion. Examples of 

 quantitative traits are life history and performance traits. Because the 

 majority of adaptive evolution in a population is based upon changes in 

 quantitative traits rather than in qualitative traits (Lande and 

 Barrowclough 1987), maintenance of genetic variation for quantitative 

 traits is required to ensure long-term perpetuation of fish stocks. 



C. Hierarchical organization of genetic variation - includes 

 variation in alleles within an individual's genotype, genetic variation 

 between individuals within stocks, and genetic variation between 

 stocks within a species. These three levels of genetic variation 

 constitute the entire genetic diversity of a species. Hatchery-related 

 policies and guidelines must be concerned with all three levels of genetic 

 diversity because adaptive evolution and long-term persistence of the 

 species depends on them all. 



Some genes within stocks may be organized as coadapted gene 

 complexes. These are combinations of genes occurring in many individuals 

 because they have functioned well together over many generations of 

 natural evolution in the local environment. Occurrence of coadapted gene 

 complexes and their relevance in environments highly altered by human 

 activities (e.g., many parts of the Columbia River Basin) is not yet well 

 documented in salmon and steelhead (Allendorf et al. 1990). 



1.3 Stock Definitions in Agency Documents 



Documents FWS-2, IDFG-1, and ODFW-1 contain some definitions of stock 

 categories. Definitions from these three documents fit under four possible 

 headings based on different breeding histories of ancestors, particularly on 

 the degree to which interbreeding with hatchery-released fish may have 

 occurred: (1) hatchery stocks, (2) wild stocks, (3) natural stocks, and (4) 

 transplanted stocks. Using these four headings. Appendix II compares the 

 definitions found in the three documents. Definitions of hatchery and 

 transplanted stocks may overlap because a hatchery stock may originate 

 from a transplanted stock or from local stock. The category, natural stocks, 

 is meant to be intermediate between wild and hatchery stocks. Appendix 

 IV defines this report's usage of "wild" and "natural" stocks. 



