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[Bassonator]

http://www.cbc.ca/news/canada/british-columbia/story/2011/07/11/bc-adipose-salmon-hatchery.html, interesting read.

[Rodney]

"Big Ape" in the comment section of that article doesn't understand why he catches four times more wild fish than hatchery marked fish and questions DFO's numbers.

Is it possible that hatchery marked fish are being retained by other anglers as they return to the system so the chance of encountering them becomes less as the season progresses?

The sad/funny thing is that eight others so far also have the same skepticism.

[Every Day]

I believe it also has a lot to do with genetics.
I'm convinced that a large majority of the hatchery fish that go through don't even snap at anything and when they are used as brood those genes are passed.
Maybe more so that they have the knowledge to shoot through right away rather than stage and work up river.

Also add in all the rippers spooking fish, hatchery fish being picked off, etc you're gonna catch way less hatchery fish.

I also like how he said they don't clip sockeye.

Tried to reply to it but it didn't go through I guess 

[skaha]

--scientists often put "MAY" in a report when they cannot prove their hypothesis thus it is just opinion.
--easiest thing is to say "NO" to the practice how about giving a viable cost effective alternative.

[Rodney]

Here is the abstract of the study in case anyone's interested in reading it.

A wide variety of rudimentary and apparently non-functional traits have persisted over extended evolutionary time. Recent evidence has shown that some of these traits may be maintained as a result of developmental constraints or neutral energetic cost, but for others their true function was not recognized. The adipose fin is small, fleshy, non-rayed and located between the dorsal and caudal fins on eight orders of basal teleosts and has traditionally been regarded as vestigial without clear function. We describe here the ultrastructure of the adipose fin and for the first time, to our knowledge, present evidence of extensive nervous tissue, as well as an unusual subdermal complex of interconnected astrocyte-like cells equipped with primary cilia. The fin contains neither adipose tissue nor fin rays. Many fusiform actinotrichia, comprising dense striated macrofibrils, support the free edge and connect with collagen cables that link the two sides. These results are consistent with a recent hypothesis that the adipose fin may act as a precaudal flow sensor, where its removal can be detrimental to swimming efficiency in turbulent water. Our findings provide insight to the broader themes of function versus constraints in evolutionary biology and may have significance for fisheries science, as the adipose fin is routinely removed from millions of salmonids each year.

J. A. Buckland-Nicks1, M. Gillis and T. E., 2011. ReimchenNeural network detected in a presumed vestigial trait: ultrastructure of the salmonid adipose fin

http://rspb.royalsocietypublishing.org/content/early/2011/07/06/rspb.2011.1009.abstract

[cutthroat22]

The lack of the interconnected astrocyte-like cells equipped with primary cilia is my new explanation for Capilano coho lockjaw.  They just can't sense my lure.

[JAwrey]

The lack of the interconnected astrocyte-like cells equipped with primary cilia is my new explanation for Capilano coho lockjaw.  They just can't sense my lure.

 

[Dave]

This issue should be interesting to watch.  Someone on another site said they hope this information will be studied both properly and soon; couldn't agree more.

[StillAqua]

Adipose clipping is like circumcision. No real science, just a lot of faith that the fish will be ok after it's mutilation.

So that's why I never made the Olympics....my performance was inhibited. Where's my lawyer's number? 

[skaha]

This issue should be interesting to watch.  Someone on another site said they hope this information will be studied both properly and soon; couldn't agree more.

--also used to be popular to remove tonsils and adenoids.. then some started thinking... these body parts served some purpose and should not be removed at the first sign of inconvenience.
--if I had to make the choice for spending research dollars I'd choose to spend more on ways to reduce the necessity of hatchery fish supplement.
--identification of hatchery stock by clipping of adipose or other fins... if they disadvantage the hatchery stock over naturals for survival may be its a good thing.