Best Management Practices – A Tool Not a Rule
Several common BMPs for recovering natural populations include: achieving 100% marking on hatchery production, implementing selective harvest regimes, maximizing natural origin fish utilized in hatchery broodstock, and minimizing hatchery fish on spawning grounds. Failure to fully implement one or all of these is commonly perceived as a death sentence for the natural population. We utilize ESA listed Snake River fall Chinook to explore “how good is good enough”? Only 50% of Snake River fall Chinook hatchery production is adipose fin clipped and 22% release unmarked; 30% or higher are subject to non-selective harvest; and utilization of natural origin fish in hatchery broodstocks was intentionally avoided for the first 30 years of the program. During the last ten years hatchery fish have constituted 67% of natural spawner escapement. Yet, natural origin abundance has increased 10 fold since the 1980’s. The current 10 year geometric mean of natural origin abundance averages 5,000 fish; exceeding the recommended ESA delisting abundance criteria.