Pacific Salmon: Wild, Enhanced, Hatchery, Farmed - Four Different Fish, Patchwork Management Is Not Working

Wild Pacific salmon are genetically diverse, in part in response to the unique characteristics of the rivers and lakes they use to spawn and rear in. Spawning channels reduce critical environmental challenges and may diminish diversity and thus resiliency. Hatchery salmon cannot select their mates and thus lose the ability to tune themselves genetically to changes in their freshwater systems. Farm salmon have a very different life history – with schools of approximately 600,000 remaining in one location for up to 2 years confounding mechanisms that limit intergeneration pathogen transfer.   Wild salmon threaten farm salmon with pathogens, which farm salmon in turn can amply and threaten free-ranging salmon. Hatchery and spawning channel salmon could degrade wild salmon genetic resilience.   Because these four types of salmon may be incompatible, harming each other, restoration efforts could benefit from recognition of these dynamics and a clear choice to select one type salmon as top priority.  Wild salmon may be the most cost-effective and best equipped to survive climate change.