151 



26 



2. biological characteristics of adults returning to the hatchery; 



3. location, size, identity, and performance of naturally spawning stocks in 

 close proximity to hatcheries; 



4. efforts to keep different intraspecific stocks reproductively separated in 

 hatcheries; and 



5. incidence of accidentally produced interspecific hybrids. 



5.5 Improvement of Genetics Research and Monitoring 



Conservation of salmon and steelhead genetic resources depends heavily 

 on proper understanding of natural evolutionary processes and impacts of 

 hatchery programs on these processes Such understanding will only come 

 from well designed research and monitoring as outlined below. A 

 particular recommendation may contain both research and monitoring 

 components. Details about research and monitoring methods are beyond 

 the scope of this report. The topic of appropriate methods is introduced by 

 Riggs (1990, Appendix VI) and Lande and Barrowclough (1987, pages 114- 

 119). 



A. Develop evolutionarily valid criteria for assigning wild or 

 natural stock status to naturally reproducing fish 

 populations. 



Factors to consider include history of stock transplantations, natural 

 demographic history of the population, generations of interbreeding with 

 hatchery stocks, magnitude of interbreeding with hatchery stocks, and 

 genetic tag data (e.g., from DNA analysis). Uncertainty about these factors 

 must also be considered in a biologically rational manner. 



B. Monitor levels of genetic variation for life history traits in 

 hatchery stocks. 



Standard methods of quantitative genetic analysis are especially 

 appropriate because they assess polygenic variation for quantitative traits. 

 Such polygenic variation is most important for adaptive evolution of 

 managed populations in natural environments (section 12.1.B). 

 Determination of single gene variation, as done by analysis of protein 

 polymorphisms or DNA, is of secondary importance for ensuring long-term 

 perpetuation of fish stocks in natural environments but is a useful and 

 complementary tool for addressing certain questions. 



