The California Water Blog is written by actual scientists who know more about California’s trout, salmon and steelhead than pretty much anyone on the planet, so when they post something definitive, you’re smart to sit up and take notice.
Like these on the insanity of California’s fragmented salmon & water management:
The past 60 years of Central Valley hatchery production to support fisheries has resulted in replacement of multiple natural populations with one hatchery population, thereby greatly increasing extinction risk.
The situation is similar to managing financial investments for long-term yields, where a well-diversified investment portfolio (i.e., multiple runs with multiple independent populations) will fluctuate less in response to volatile market conditions (i.e., environmental variation) than will one concentrated in just one or two stocks (i.e., just hatchery fish).
Today, the management portfolio of Central Valley salmon is overwhelmingly concentrated in hatchery production. This all-eggs-in-one-basket strategy is an underlying cause of the recent collapse of salmon numbers (Lindley et al. 2009). Recovery of self-sustaining runs of Central Valley salmon will be impossible if we do not stop interbreeding between hatchery and naturally spawning populations (Katz et al. 2012).
There it is. Plain as day.
Biologists are often reluctant to make statements that will play in the political arena; it’s far safer to simply state the hatchery salmon aren’t as productive as wild salmon, and that releasing vast numbers of them suppresses wild populations.
Here, Moyle and Katz lay it all out for us; recovery will be impossible as long as rubber trout (and habitat loss, and massive delta pumping, and whatever else) continue to gum up the works.
But that would be a commercial disaster, right? All those fish that commercial salmon fishermen couldn’t catch?
Well, don’t look to closely, but commercial salmon fishermen haven’t been doing too good since about 2006 or so.
What’s needed to get California’s salmon populations back on track? Lots of things, starting with:
Because of the fragmented nature of the current system of salmon management, we spend tens of millions of dollars annually to produce salmon in inland hatcheries, and then spend hundreds of millions more to deal with the environmental, regulatory and legal consequences of having produced those same fish.
As was suggested for water management in the previous blog, this piecemeal approach to fisheries resource management is not economically viable. Nor is this strategy viable for avoiding extinction. Accordingly, a comprehensive re-thinking of hatchery management must be undertaken in California and where adverse impacts to natural spawning populations outweigh benefits, hatcheries should be closed.
See you eating all the hatchery fish I can catch, Tom Chandler.