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3.7.4 Rearing Practices 



A. Reduce artificial selection and hatchery-induced family size 

 variation during incubation, rearing, and in fish releases. 



Maintain uniform rearing conditions for all fish of the same stock. Avoid 

 non-random culling of progeny during incubation, rearing, and in fish 

 released. Evaluate the use of volitional releases as a means of reducing 

 inadvertent selection. 



B. If artificial selection programs are planned or practiced, 

 evaluate if they are consistent with genetic conservation 

 goals. 



Require small-scale experimentation prior to full adoption of an intentional 

 selection program. Require: well-defined goals; assessment of changes in 

 genetically correlated traits; monitoring for progress towards stated goals; 

 and monitoring for impacts on genetic resources and life history patterns 

 of wild and natural stocks with which the selected stock may genetically 

 interact. 



C. Consider quantitative assessment of the potential that 

 hatchery environments inadvertently select against life 

 history traits important for fitness of hatchery-reared fish 

 in natural environments. 



A scientifically sound research and monitoring program would be needed 

 to assess the circumstances under which this concern is valid. Examples of 

 hatchery environmental conditions to examine are incubation and rearing 

 temperatures, rearing densities, and timing and site of releases. 



3.7.5 Size of Donor Stock Remaining to Reproduce Naturally 



A. Ensure that numbers of individuals remaining to reproduce 

 naturally are sufficiently large to prevent avoidable losses 

 of genetic variation in the donor stock. 



B. Prevent selective removal of adults to ensure existing life 

 history patterns of the donor stock are conserved in 

 individuals remaining to reproduce naturally. 



