Triploids

[FFSBC]

Please visit our Facebook page to see our response to the letter to the editor written by John Hoar on April 1st to the Columbia Valley Pioneer.

 

FFSBC Facebook page

[ÜberFly]

Can't find it?!

 

Never mind... Found it...

 

Please visit our Facebook page to see our response to the letter to the editor written by John Hoar on April 1st to the Columbia Valley Pioneer.

 

FFSBC Facebook page

[monger]

I talked with a researcher who is involved in a huge study in BC. They are looking into a variety of angling issues in about 800 lakes. They are looking at angling methods, regulations, fish growth, angler density and a number of other issues. They are using aerial sampling methods to watch boat density and distribution as well as using webcams to observe angling effort. One thing he said was that BC will switching their rainbow stocking completely to All Female Triploids so there won't be any males to worry about.

It would be great to see a bit more research funding directed toward Alberta's fisheries. How much Alberta's fisheries are valued is very evident by the lack of money made available to study them.

[dryfly]

The article originally posted here is a bit silly and a couple of responses are quite out of the ball park. Several have already correctly pointed out that trips give a much reduced risk of hybridization if they "escape." True.

 

But let us not forget that rainbows in our rivers are not native in the first place. Some folks seem to be suggesting that there is a potential issue if hatchery fish from lakes get into a river that was originally stocked with non-native hatchery rainbows. With the exception of some pockets of pure-strain cutts in Alberta (and the Athabascan rainbows), generally speaking our sport trout fishery is artificial. Striving to protect those pockets of cutts and Athabascans is worthwhile, but that's another story. This is about trips and hatcheries.

 

There is a misconception that our hatchery fish are on par with domesticated species of cows and dogs. (Selecting and breeding domestic livestock and crop plants is another story, but has led to a well-fed world with exceptions that are political vs. genetic.) There is no similarity between hatchery trout and (say) domesticated dogs with their hip dysplasia and progressive retinal atrophy, etc. Provided the hatchery biologists are indeed maintaining some level of genetic heterogeneity our hatchery trout are decent stock. It is incorrect to suggest that heterogeneous hatchery-raised fish are inferior to "wild stocks" when their parentage is de facto wild stock and continually assess for heterogeneity.

 

While writing an article on rainbow trout for the 2009 AFG, I interviewed Jon Underwood from the Allison Creek hatchery. Jon also sent me some notes that he had prepared. Here are my notes as taken from the draft of the article. I think the words are the same in the final article.

Since we have no native rainbows in Alberta—other than the Athabasca strains—you may wonder about the genetic lineage of our stocked rainbow trout today.

 

The genetic history of rainbows stocked decades ago in Alberta is murky at best. However, according to Jon Underwood, Head of the Allison Creek Brood Trout Station near Coleman, the first strains of rainbows released in Alberta probably consisted of several stocks from the northwest United States and from Beaver Lake in BC.

 

For supply and disease reasons, the province stopped importing eggs from other hatcheries and since 1982 no eggs have been brought into Alberta. Today, the province maintains two separate brood stocks of rainbows consisting of three genetic lines.

 

The Raven Brood Trout Station uses brood stock that originated at the Mt. Lassen Trout Farm in California. The Allison Creek Brood Trout Station uses two strains today. One originated at Beity Hatcheries in Washington and the other is a strain that combined genetics from the Beity line and from Pennask and Beaver lakes in BC.

 

Jon Underwood reports that the genetic diversity is maintained in Alberta’s rainbow hatchery stocks by using a rotational line crossing system. This is a proven system that reduces chances of inbreeding (that reduces genetic variation) and DNA analysis has shown that there is good genetic diversity in Alberta’s stocked rainbows.

So at the end of the day let us not forget that our rainbows here are not native. (Not including the population of Athabascans which are probably a glacial artifact.) We've created an artificial fishery that we try to manage with genetically heterogeneous lines of hatchery fish. I suspect that the folks at the hatcheries are doing a pretty good job. They won't get any complaints from me with what they've produced for Bullshead and Police.

 

And it came to pass that the sun finally emerged ... and I am going for a walk with my camera!

[ironfly]

Thanks, dryfly.