Common hatchery practice could be harming salmon

[Sushihunter]

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

Common hatchery practice could be harming salmon

The Canadian Press

Posted: Jul 11, 2011 12:56 PM PT

Last Updated: Jul 11, 2011 12:56 PM PT

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A year-old sockeye salmon peers through the glass of a lab beaker. Darin Oswald/AP

The common practice of clipping the small back fin of salmon to discern hatchery raised fish from wild may not be as harmless as experts once believed.

In an environment where every step counts for salmon survival, a study from the University of Victoria suggests hatcheries may need to find another way to mark their fish.

Biologist Tom Reimchen's study found the adipose fins are in fact a sensory organ that is especially important when the fish is swimming in turbulent water.

Experts long believed the tiny fin between the dorsal and tail was like cutting a finger nail, but Reimchen says it's more like removing a hand — damaging but not necessarily deadly.

With the tiny fin removed, he says the fish need to use much more energy to maintain position and speed in the water.

He's not sure how many fish might be lost because of the practice, but says the Department of Fisheries may want to investigate new methods of marking hatchery fish.
© The Canadian Press, 2011

 

[Cuba Libre]

That sure turns the turnip patch over!!! But I would be a little careful about putting to much into this report without further studies. There is data that NOT marking the fish may also be harmful to stock genetics etc--

In some hatcheries and study streams the fry are not clipped. Instead they get a coded wire tag or other electronic tag that is electronically detected when they return to the stream, or in the fish processing plan.


But I hope they continue the study... if a known portion of clipped fish die, then the hatchery should be able to compensate to a degree.

 

[chris73]

I talked to the Sooke Salmon Enhancement Society about this today and they confirmed that they have been talking to this scientist for some time now about this very issue. Bottomline what the scientist said is while a few clipped fish may have a handicap the benefits from the science to be had from clipping by far outweigh the negatives.

 

[Peahead]

I talked to the Sooke Salmon Enhancement Society about this today and they confirmed that they have been talking to this scientist for some time now about this very issue. Bottomline what the scientist said is while a few clipped fish may have a handicap the benefits from the science to be had from clipping by far outweigh the negatives.

True, but through further research it sure would be a bonus if there was a different method to hatchery mark fish that would not handicap any fish, be less labour intensive and maybe even less costly.

 

[Little Hawk]

They could try lopping off an ear instead?

 

[wolf]

HMMM interesting... One only has to look at the US for there hatch program and especially the columbia river... seems there record numbers of fish returning are not "handicapped" better than ever and that is one fast moving river.... I think they are ok remeber this is a place where bunnies ruled the roost they need something else to "SAVE" LOL LOL..just wait the deer cull comes next ....

wolf