Saturday, June 11, 2011

Genetically Different

The common argument in favor of broodstock hatcheries is that the fish they put into the river are genetically the same as the native fish in the river.  These hatcheries use only wild fish for brood.

How genetically similar are these fish.  There is plenty of science stating that first generation hatchery fish are changed solely by being in the hatchery environment.

Taking away the changes from being raised in concrete, are wild broodstock a good place to start when looking to replicate wild genetics in a hatchery environment.  One study from Oregon shows how much we have to learn about wild steelhead and genetics.

Wild rainbow trout critical to the health of steelhead populations

This study shows that "up to 40 percent of the genes in returning steelhead came from wild rainbow trout, rather than other steelhead."  While the number may be higher in Hood River than in coastal rivers (it may be less) it shows how much genetic material is added by resident rainbows to the steelhead population.  Not only should this be a call for more restrictive regulations on trout fishing in all coastal rivers but it should make us rethink whether we can ever hope to recreate wild steelhead genes in a hatchery environment.  The Snider program on the Sol Duc is a prime example.  Like all hatcheries, they use a small number of adult wild steelhead to create many hatchery fish.  This narrows the gene pool in the returning hatchery fish which are allowed to spawn if not harvested (no trapping of returning hatchery adults happens) and pass that narrow gene pool on to future generations along with having reduced productivity.  If one of these hatchery X wild or hatchery X hatchery crosses returns and then is used as broodstock the genetics shrink even more.  By using only steelhead for the brood, one is excluding possibly 40% of the genes of the native fish.

We have a chance on the Sol Duc to remove a damaging hatchery program and designate the healthiest steelhead river left as a wild gene bank.  This is truly an opportunity we cannot miss out on.  We have until June 30th to send in our comments to  The Native Fish Society has also put together an easy way to support the removal of this damaging program.  Click the link below to comment.

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