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[BBarley]

Interesting article in the Globe and Mail today regarding overcrowding in the North Pacific ocean.

http://www.theglobeandmail.com/news/national/british-columbia/north-pacific-overcrowded-with-salmon-as-population-soars/article1740524/

It seems hatchery produced salmon from Asia and Alaska could be linked to poor survival of wild salmon stocks all over. Perhaps the mystery behind the Fraser sockeye crash could be linked to Alaska's salmon ranching program?? It definitely stands to reason that the ocean can only naturally provide so much food for the multitude of species that depend on it.

Thought or comments?

[StillAqua]

Funny how Alaskans won't allow fish farms in their coastal waters but they have no problem raising millions of genetically inferior juvenile salmon and dumping them into the ocean so they can compete and possibly interbreed with wild salmon. "Ocean ranching" should be banned by international laws of the seas. We could start by banning salmon products in Canada from countries that participate in ocean ranching.

[lovetofish]

Interesting article in the Globe and Mail today regarding overcrowding in the North Pacific ocean.

It seems hatchery produced salmon from Asia and Alaska could be linked to poor survival of wild salmon stocks all over. Perhaps the mystery behind the Fraser sockeye crash could be linked to Alaska's salmon ranching program?? It definitely stands to reason that the ocean can only naturally provide so much food for the multitude of species that depend on it.

Thought or comments?

Maybe the ocean cannot provide enough food for all these hatchery fish beacuse so much biomass is harvested from the ocean to feed fish in fish farms?

[lovetofish]

Funny how Alaskans won't allow fish farms in their coastal waters but they have no problem raising millions of genetically inferior juvenile salmon and dumping them into the ocean so they can compete and possibly interbreed with wild salmon. "Ocean ranching" should be banned by international laws of the seas. We could start by banning salmon products in Canada from countries that participate in ocean ranching.

I don't know Alaska's situation regarding brood stock, but I thought that here in B.C., only wild stock are used for brood stock in hatcheries.  Therefore these hatchery fish will not be genetically inferior to the wild stock as their genetics comes from their parents and not their environment. They may not have the "smarts" of the wild reared fish, beacuse they were raised in a controlled environment  but those that survive to return to their natal streams are obviously not inferior to their wild counterparts. The only difference genetically between hatchery raised fish from wild brood stock and wild fish is the fact that wild fish choose their mate themselves.

[StillAqua]

Most hatcheries use the fish that were born and raised in the hatchery because those are the fish that home to the hatchery water and capture facility. Some hatcheries and captive raise facilties do grab some wild fish and add them to the egg and milt pools. The reason they do this is because any time you select or limit the number of fish in a population that can spawn, you reduce the genetic diversity of the population. Genetic diversity is the "insurance" that wild fish have against unusual environmental conditions, ensuring that some fish will always survive to spawn.

The other problem with hatchery breeding is you eliminate the very strong natural selection that occurs on the spawning grounds. Competition among males for females, competition of females for the best spawning areas, timings of spawning and fry emergence, water temperatures and flows are all natural selection forces that shape the characteristics and genetics of wild salmon populations. If you eliminate these natural selection forces in a hatchery environment, the hatchery population will genetically drift away from the wild type and become domesticated.

BC hatcheries are well aware of these problems and try to keep the hatchery gene pools high with wild genes and clip their fish so they can be distinguished. But I doubt the large industrial hatcheries in Russia and Asia that dump billions of chum and pink fry into the ocean take that level of care; they are meat hatcheries. There are now more chum salmon in the north Pacific from their hatcheries than wild chum.

[Dave]

Well written StillAqua.  Good to see Alaska's little secret is finally being recognized for the problem it is.

[BladeKid]

Lets say two hatchery fish spawn together, their offsrping will clearly not be clipped, therefore when these fish (the offspring) return, they will be considered "wild fish"........ thoughts anyone.

Michaelt

[BladeKid]

Now that I think, I guess it leads back to the article, in that fish pops. will slowly be "domesticated" and the genetic varialbilty will then become smaller.   
 
again, your thoughts..

[BBarley]

I think as long as we try and play god, we're going to see a downward trend in everything. Cows grazing on grass grown on what used to be rainforest, something wrong with that picture.

I would rather see fish farmed in heavily regulated fashion, then have millions upon millions of hatchery raised fish turned loose into the open pacific to compete with wild salmon. Our food today is grown utilizing maximum yields on small portions of land. Whats better, having 200 cows raised on 200 acres of land, or 200 cows raised for a year then turned loose to fend for themselves?