As a fisherman and member of Trout Unlimited, I hear a question asked on a regular basis to the effect, “If our trout populations are declining, why don’t we just supplement with hatchery fish?” That a question like that could even be asked given our history with hatchery fish still grates on my nerves.
There have been several articles in the last few days on this question that you should probably be aware of. This morning from the conservation blog at Field & Stream magazine came an article by Hal Herring titled, Hatcheries, Frankenbucks, Disease: When Will We Learn?
In essence: we trade or allow others to trade, our birthright–in the case of salmon aquaculture; clean, mighty rivers, and salmon, living unimaginably wild lives in the open ocean, and returning to spawn in feeder creeks so small that we can step across them, for huge pens, anchored, polluting, protected, filled with facsimile-fish so weak, so pale compared to the real thing, that their very flesh must be dyed orange with harvested krill before anyone will purchase or eat it. The diseases and parasites that flow out from these operations imperil the very survival of the native species, and the economy and ecology that they support.
Hatcheries certainly have their place and have been used for more than a hundred years to provide fisheries that would not otherwise exist. In nature there is a reason why fish don’t exist in sterile reservoirs or polluted streams. The use of hatchery fish to replace a fishery that we may have destroyed or that would not otherwise exist can sometimes be economically justified. What hatcheries cannot do is provide solutions to why the fishery was destroyed in the first place or help to provide remedies. Hatchery fish are a very poor substitute for the wild fish that they replace and they should certainly not be employed on top of a healthy, or even depressed population of wild fish to “improve” our ability to catch something, or anything.
Hundreds of millions of dollars have been spent over the last few years to remove two dams on the Elwha River in Western Washington. Those two decrepit dams were built to provide electricity to the burgeoning new west coast population. That the dams destroyed amazing runs of pacific salmon and steelhead was hardly considered at the time. There were millions of such fish available and one small run in one small river would not be missed. Now the entire metapopulation of pacific salmon is considered in dire straits. Removal of the Elwha Dams was done to hopefully restore ninety miles of spawning habitat to restore historic salmon runs. In order to speed recovery of the salmon and steelhead runs, the Lower Elwha Klallam Tribes have proposed a new salmon hatchery to the lower Elwha. Four conservation groups filed suit yesterday to block the hatchery plans.
The groups support the right of the Lower Elwha Klallam Tribe to harvest salmon and steelhead, but argue that intensive hatchery production throughout the recovery will reduce the capacity of wild salmon and steelhead to recolonize the newly available habitat, harming ESA listed Puget Sound steelhead, Chinook salmon, and southern resident killer whales that depend on Chinook salmon for their survival.
In California, studies have found that less than 10% of the wild fall-run chinook population remains in the Mokelumne River due to massive dumping of hatchery stocks into the river.
Why does it matter whether you are catching wild or hatchery fish? That question has been long and extensively studied. Most anglers can tell you the difference between a wild fish and a hatchery clone on the other end of a line. The hatchery fish simply are not equivalent to a healthy wild salmon or trout. Hatchery fish have been bred for decades to survive in concrete raceways, and they do so very well. Survival in the wild is another matter. In a recent study from Oregon State University, researchers found that, “a fish born in the wild as the offspring of two hatchery-reared steelhead averaged only 37 percent the reproductive fitness of a fish with two wild parents, and 87 percent the fitness if one parent was wild and one was from a hatchery. Most importantly, these differences were still detectable after a full generation of natural selection in the wild.”
The implication, Michael Blouin [OSU professor of zoology] said, is that hatchery salmonids – many of which do survive to reproduce in the wild– could be gradually reducing the fitness of the wild populations with which they interbreed. Those hatchery fish provide one more hurdle to overcome in the goal of sustaining wild runs, along with problems caused by dams, loss or degradation of habitat, pollution, overfishing and other causes.
The solution, of course, is that it is that we must always be judicious in our use of synthetic fish. It is always better to correct the habitat, or other problems that have caused a decline in fish populations rather than attempt to mask the problems through the addition of genetically and physically inferior hatchery or farmed fish.
