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(This post comes with a request to keep this thread civil.)

Found in the Telegraph Journal today (can't post a link as they require a subscription now to see stories online): 73 aquaculture fish found in the Mag's counting fence this year, of varying sizes and indicating they might have been a series of small escapes rather than a single large one. No major escapes were reported by aquaculture companies. Compare this with only five wild salmon returned to spawn in the Mag this year and only one last year despite substantial investments in trying to rebuild the population.

The article shares some other snippets like how there was at one time 500 native salmon at the counting wall, and how in 2005 massive vandalism caused a huge escape of thousands of farmed salmon at Deer Island. Some 30 of those made it to the Mag in that following year, with 45 showing up in other Charlotte County rivers.

Now the question: I understand that farmed salmon aren't the same genetically as original New Brunswick stock, but isn't the quantity of "now-wild" salmon more important than the quality of a single genetic strain that appears to be in very heavy decline? Will it ever make sense to attempt to interbreed farmed and wild salmon deliberately as a way to sustain the stock and the industry? It seems like although Man started the ball rolling, Nature is going this way.
 

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It's worse than that. Apparently a couple of thousand of Cooke's farmed salmon escaped a couple of days ago and are in the Mag. The problem with the excapees mixing with the wild is that (I'm told) they will weaken the strain of wild salmon, which have develloped their own strenghts and immunities or whatever for their particular stretch of water, i.e.- Miramichi salmon are genetically different from Saint John salmon in that they have develloped themselves over thousands of years to be able to "live" will in their river system. Throw some Cooke's salmon in the mix and they become weaker. Something like that, anyways.
 

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Just my opinion, but....

I think you have to think about the sort of 'selection' process that is undertaken by the aquaculture industry, vs the selection process that occurs in the wild. For caged fish, you want a fish that will grow fatter faster, without wasting a lot of energy on reproductive processes, doesn't mind being crowded, and enjoys swimming in a clockwise (or counterclockwise) direction for months at a time. (basically, the NASCAR of the fish world). You want a fish that will feed on pelletized food constantly, without those bothersome fasting periods that wild, anadromous fish go through (although clearly, once freed, some DO head for fresh water!). You don't need adaptations like flight from predators, seeking cooler water or shade, stuff like that. Not saying those instincts are gone, just that there is no selection at play to weed out the fish who lack those tendencies.

I have NO idea if these characteristics would get transferred to wild fish with which they might breed once they escape, nor whether they even remember what their gonads are for, but myself, I'd rather not take the chance.

I suppose five years after the last wild salmon shows up at the fish ladder on the Magaguadavic, it might make sense to let these droids through. Maybe after a few years, they'd have a chance to revert to a more wild condition, and there'd be salmon fishing on the Mag again. Might be fun to hook a big fish that immediately starts spinning in ever-tightening clockwise circles in the middle of the pool. Besides, it would herald in a whole new set of salmon flies, mostly brown deer hair trimmed into cubes. Like the Corey, or the Purina Salmon Chow fly. Think I'll hit the vise and get started....

(hope that wasn't uncivil....)
 

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My favorite example illustrating what MIGHT happen comes from Czechoslovakia in the 70s. It involves a type of mountain goat, but the principle holds for fish in theory. The goats went extinct from the country after years of overhunting and poaching. They successfully re-established a population by bringing in individuals from the neighbouring country of Austria, where climate and conditions were very similar. Later on, for some unknown reason, they brought in more from Turkey where spring comes much earlier. The result was that the hybrids started giving birth in the middle of winter... and they went extinct again.

I am not saying this will happen in the Mag, but there is potential for weird things to happen.

Five salmons does not make for a real strong wild population... at what point should the escapees allowed in the river is an open question. I like the idea of 5 years without a wild showing up.
 

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I was under the understanding the farm raised salmon are, basically, a sterile fish. A genetically altered fish that grows far more rapidly than wild native salmon. They eat, crap, get fat and die. I can't see them surviving well as they have no instincts to feed except when fed.
 

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I was under the understanding the farm raised salmon are, basically, a sterile fish. A genetically altered fish that grows far more rapidly than wild native salmon. They eat, crap, get fat and die. I can't see them surviving well as they have no instincts to feed except when fed.
Nope, they are not sterile. However, not all that escape are sexually mature, either, depending on the life stage they are at. Escaped salmon that are sexually mature and who enter rivers can and will spawn with wild salmon. This was told to me by the Atlantic Salmon Federation.
 

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Discussion Starter · #7 ·
A precision point, but farmed salmon are not "genetically altered" (i.e. they are not "frankenfish").

They are likely to have been selectively bred (not genetically engineered like some resistant crops) to enhance certain traits such as fast growth and percentage-of-muscle-vs-fat based on picking the best bulls and females for sperm and eggs that go into the hatchery. This is no different from us breeding the fastest greyhounds to get better offspring though.

This still creates a potential problem, as noted above, that this selective breeding may come with penalties for other things that wild salmon have more of, like resisting fish lice or lamprey attacks, surviving periods or conditions of low oxygen or food supply, temperature resistance, etc.
 

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Another complementary note: the technology to produce sterile fish is there. By submitting the embryos to different treatments, it is possible to obtain triploid fish (gives them an extra set of chromosomes) making it virtually impossible for them to breed. Problem is... guess what... it is more expensive.
 
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