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Author Topic: Lethal virus from European salmon found in wild BC salmon  (Read 244814 times)

Bassonator

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #630 on: January 15, 2012, 10:04:41 AM »

Morton and Staniford are on their way to Victoria with cutting boards in hand http://www.cbc.ca/news/canada/british-columbia/story/2012/01/15/nb-bc-virus-outbreak.html....... ;D
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Sandman

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #631 on: January 15, 2012, 03:24:46 PM »

A moments thought will make it very clear that all of those effects are effects on the farmed stock which don't have the option to swim away.

You assume of course that the fish would swim away if they had a choice, but clearly those wild fish caught in the fish net pens chose not to swim away.  One also wonders how many swam away while they were still small enough, after staying in the pen for a few weeks? Only to pass on a few anti-bacterial resistant pathogens to their cousins?  We will come back to those later.

Whether or not it was a government order is irrelevant; the farms willingly followed the fallowing program. As is so often the case with reactionary arguments, semantics are used to imply the industry wasn't fully co-operative and supportive.

So they had a choice not to follow the government order?  I did not realize that.  I did not say they were uncooperative and non-supportive, I merely questioned why, if they already fallowed (and I know they did) and they already developed the best practices (that I am not convinced they did) to minimize their effects on the environment (and the wild fish that use it), did the government need to order them to do so.  Why were they not already fallowing during out migrations of wild fish?  Obviously the timing of their fallowing, prior to the government order, was at their convenience, not the environment's.  Of course they will comply when the government tells them to, they want to stay in business.  I get that.  However, I can not help but feel that their reasons for doing so are a little more self-serving and a lot less environmentally responsible than you suggest.

There is no question that farms contribute to sea lice numbers...

I know that.  You know that.  I also would also bet the farmers know that (since controlling the lice numbers is costly to their bottom line).  However, the DFO apparently does not know that, as they clearly call that very fact into question on the FAQ sheet I quoted earlier.  It makes you wonder whose interest they are really protecting.


It is the final outcome on which results are measured and judgments made, not the existence of some contributing factor. While disease pathogens are shed during outbreaks, the pathogens have extremely short lives in the absence of a host.

which they would find as the pens are on major migratory paths of wild salmon.

Those pathogens, should they contact a host, must also be able to overcome the immune response of the host in order to infect them. Since all the pathogens that affect farm fish come from the wild, the wild fish have been exposed and have developed immune responses.  Species' disease susceptibility varies so pathogens which may harm farm fish have no effect on wild fish. Even farm fish have an immune response that wards off pathogens. A disease can take hold in a farm environment only when stress levels in the fish compromise their immune response.

And the fact that they are crowded in pens does not cause them stress? 

Quote from: Folke & Kautsky, 1992
The rapid expansion of intensive one-species aquaculture has generated severe environmental as well as socio-economic problems. . . The characteristics of one-species aquaculture, such as intensive throughput-based salmon cage-farming and shrimp pond-farming, are found to be similar to those of stressed ecosystems".

Could a farmed salmon not pick up a case of IHN, VHS, or ISA or what have you, and since they have little immunity to that disease and are stressed by their confinement to such a small area, have that disease propagate and thrive to the point of the farmers having to try to fight the disease with chemicals?  Then could that farmed salmon (assuming it has survived long enough) then pass that disease to other wild salmon as they are passing the pens on their way back to the rivers to spawn (a highly stressful activity)?  Then would this not increase the likelihood of those wild salmon dying from the disease?  Would it not make sense to not have these potential sources of disease on the migratory paths of wild fish already stressed to the point of collapse?


That is because the effects are indeed very minor and contained to very small areas.They have no long term effects and make no permanent changes. They are a very minor but necessary cost of obtaining the benefits that the industry provides.

You keep saying they are minor, but the research I have read says otherwise.

Quote from: White et al., 2004

Like other forms of intensive food production, industrial-scale fish farming generates significant environmental costs . . .The expansion of some forms of aquaculture, particularly salmon and shrimp farms, has proven to be destructive to the natural environment and populations of aquatic animals. Industrial scale farming of salmon in netpens and shrimp in coastal ponds are the most problematic because they require the intensive use of resources and export problems to the surrounding environment.

Quote from: Krkošek et al., 2005 quoted in Buschmann et al., 2006
Salmonid farms can alter the natural transmission dynamics of sea lice to wild juvenile salmon with infestation pressures four orders of magnitude greater than the natural ambient level

Four orders of magnitude greater hardly seems "very minor".  Other sources claim much higher orders of magnitude (73 times) but since they do not cite specific studies we will ignore them,  but a 2003/4 Norwegian study showed infection rates 3-8 times greater around farms than in an adjacent temporarily farm free area (Bijorn et al., 2011).

It is great that you assure us that all these problems the research has shown to be the results of net pen fish farming have been solved and that the the fish farmers in BC now all operate according to "best practices."   However, you will forgive me if I remain as unconvinced as you are that that the dangers do not outweigh the benefits, which are going to be much smaller job-wise as the industry expands.  As is true in other industrialized modes of food production, when "farming methods have become more intensive, . . . employment opportunities have declined (White et al, 2004).  If you want to support fish farming, you should be supporting truly sustainable farming practices and not industrial feed lot production.
« Last Edit: January 15, 2012, 05:03:02 PM by Sandman »
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chris gadsden

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #632 on: January 16, 2012, 09:45:19 AM »

Foir those that donot have this link and want something to read on a snowy day.

http://www.cohencommission.ca/en/

absolon

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #633 on: January 16, 2012, 09:48:59 AM »

You assume of course that the fish would swim away if they had a choice, but clearly those wild fish caught in the fish net pens chose not to swim away.  One also wonders how many swam away while they were still small enough, after staying in the pen for a few weeks? Only to pass on a few anti-bacterial resistant pathogens to their cousins?  We will come back to those later.

Sounds very fearsome, but those escapees would have had to have been digging in the substrate under the pen to come in contact with any anti-biotic resistant bacteria. Even if they had, it wouldn't matter since they aren't going to be treated with antibiotics at any time. While those bacteria may be resistant to antibiotics, they are still vulnerable to the fish's own immune response.

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So they had a choice not to follow the government order?  I did not realize that.  I did not say they were uncooperative and non-supportive, I merely questioned why, if they already fallowed (and I know they did) and they already developed the best practices (that I am not convinced they did) to minimize their effects on the environment (and the wild fish that use it), did the government need to order them to do so.  Why were they not already fallowing during out migrations of wild fish?  Obviously the timing of their fallowing, prior to the government order, was at their convenience, not the environment's.  Of course they will comply when the government tells them to, they want to stay in business.  I get that.  However, I can not help but feel that their reasons for doing so are a little more self-serving and a lot less environmentally responsible than you suggest.

What you think about their motivation is considerably less important than what actions were taken. Your speculations on motive have a single purpose, and that purpose has nothing to do with fish.

Quote
I know that.  You know that.  I also would also bet the farmers know that (since controlling the lice numbers is costly to their bottom line).  However, the DFO apparently does not know that, as they clearly call that very fact into question on the FAQ sheet I quoted earlier.  It makes you wonder whose interest they are really protecting.

Perhaps you should take this up with the DFO then. There is a difference between contributing to, as I have suggested, and being responsible for, as you suggest. The DFO suggested there that farms were probably not responsible but don't suggest that they didn't contribute. Once again, there are many contributing factors to the situation. Arbitrarily ignoring all but the one you are arguing against makes for good rhetoric but poor problem solving.


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which they would find as the pens are on major migratory paths of wild salmon.

Again, arbitrarily eliminating those pesky details such as pathogen survival time in the absence of a host, degree and duration of exposure and immune response makes for good rhetoric but it also makes for a poor representation of actual circumstances and actual outcomes.



Quote
And the fact that they are crowded in pens does not cause them stress? 

Could a farmed salmon not pick up a case of IHN, VHS, or ISA or what have you, and since they have little immunity to that disease and are stressed by their confinement to such a small area, have that disease propagate and thrive to the point of the farmers having to try to fight the disease with chemicals?  Then could that farmed salmon (assuming it has survived long enough) then pass that disease to other wild salmon as they are passing the pens on their way back to the rivers to spawn (a highly stressful activity)?  Then would this not increase the likelihood of those wild salmon dying from the disease?  Would it not make sense to not have these potential sources of disease on the migratory paths of wild fish already stressed to the point of collapse?

The diseases that break out on salmon farms are caused by pathogens already in the environment. Farm salmon come from hatcheries and the fish are not exposed to the pathogens until they hit the chuck. A disease outbreaks results from the density induced stress compromised immune response and the extended exposure of infected hosts in extremely close proximity of a large number of potentially susceptible hosts. Should a wild fish come close enough to be exposed to live pathogens, it's own immune response will kick in, and because the fish lives in the same environment as the pathogen, it likely has had previous exposure and consequently has a preprogrammed response that will operate unimpeded by the stress levels that compromised the farm fish immune response. Should that response not be sufficient, it is possible that the fish become clinically infected but because the fish doesn't exist in the close proximity to the large numbers of other fish found in farm pens, the likelihood of infecting other fish is much lower and the chances of an epizootic are extremely low.

Another important factor is the differences in disease susceptibility between the penned fish and the wild stocks. An outbreak is more likely to occur in a species susceptible to a particular pathogen but will have little effect on another species that is resistant to that pathogen. Atlantics and Pacifics have different vulnerabilities; the outbreaks in the penned Atlantics often do not pose any risks to Pacifics because of that fact.



Quote
You keep saying they are minor, but the research I have read says otherwise.

Four orders of magnitude greater hardly seems "very minor".  Other sources claim much higher orders of magnitude (73 times) but since they do not cite specific studies we will ignore them,  but a 2003/4 Norwegian study showed infection rates 3-8 times greater around farms than in an adjacent temporarily farm free area (Bijorn et al., 2011).

It is great that you assure us that all these problems the research has shown to be the results of net pen fish farming have been solved and that the the fish farmers in BC now all operate according to "best practices."   However, you will forgive me if I remain as unconvinced as you are that that the dangers do not outweigh the benefits, which are going to be much smaller job-wise as the industry expands.  As is true in other industrialized modes of food production, when "farming methods have become more intensive, . . . employment opportunities have declined (White et al, 2004).  If you want to support fish farming, you should be supporting truly sustainable farming practices and not industrial feed lot production.

There isn't a whole lot of point in citing statements with a reference to author and date unless you also provide some means of identifying the paper you are citing. The reason that supporting documents are cited is not to make a presentation look as if it is very scientific, rather it gives the reader a chance to examine the source document and determine relevance, adherence to context, methodology and accuracy.

I haven't claimed anything like what you attribute to me. What I have said is that there is no direct evidence that farms are causing the declines of the wild stocks, that operating with best practices is in the financial interests of the farms and that farms respond to problems as they are identified in a manner that will best mitigate the problem. The history of the industry in the province has shown that it does not cause the catastrophic damage the reactionaries accuse it of. It is clear that the industry already supplies substantial benefits; expansion may occur but it will be controlled and regulated and monitored, and it will supply more benefits. You're welcome to disagree with the idea that the costs are greater than the benefits that are obtained, but to be convincing, you need to demonstrate that with facts.

If you want to do something constructive for the wild stocks, you should be supporting the elimination of the commercial salmon fishery.
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alwaysfishn

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #634 on: January 16, 2012, 10:14:01 AM »


If you want to do something constructive for the wild stocks, you should be supporting the elimination of the commercial salmon fishery.

I know that the very best opportunity for the salmon feedlots would be the demise of all wild salmon, as it would eliminate the competition. The second best opportunity for the feedlots would be to see the elimination of the commercial fishery and those preferred wild salmon clogging the grocery shelves.....
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absolon

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #635 on: January 16, 2012, 12:07:15 PM »

I thought that what we are concerned with here is the best option for the fish. If we are going to shut down a sector, the best option for the fish is unquestionably putting a halt to the commercial harvest. It says something about your motivation that you would rather maintain that harvest and the harm it does the stocks simply to punish the farms.
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Dave

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #636 on: January 16, 2012, 12:25:11 PM »

I know that the very best opportunity for the salmon feedlots would be the demise of all wild salmon, as it would eliminate the competition. The second best opportunity for the feedlots would be to see the elimination of the commercial fishery and those preferred wild salmon clogging the grocery shelves.....
Wild BC salmon aren’t competition for farmed fish for the simple reason there are not enough of them.  No, the real competition for BC farmed salmon are Alaska’s ranched salmon.  Good article in today’s Vancouver Sun how wild salmon coast wide are being impacted by this questionable practice.
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alwaysfishn

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #637 on: January 16, 2012, 01:10:12 PM »

Wild BC salmon aren’t competition for farmed fish for the simple reason there are not enough of them.  No, the real competition for BC farmed salmon are Alaska’s ranched salmon.  Good article in today’s Vancouver Sun how wild salmon coast wide are being impacted by this questionable practice.

The public perceives Alaska ranched salmon to be equivalent to BC wild salmon whether bought in a grocery store or a restaurant. From a look, feel, taste and cost point of view there is no perceived difference. The public knows that Alaska salmon like BC wild salmon is not fattened up on synthetic feed pellets, antibiotics or dyes.

So if Alaska salmon is competition for feedlot salmon, then I maintain BC wild salmon is as well.
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absolon

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #638 on: January 16, 2012, 01:18:36 PM »

I know that the very best opportunity for the salmon feedlots would be the demise of all wild salmon, as it would eliminate the competition. The second best opportunity for the feedlots would be to see the elimination of the commercial fishery and those preferred wild salmon clogging the grocery shelves.....


Dave addresses one of the very real flaws in your argument. Regardless of the public perception of ranched Alaskan salmon, it bears no similarity to harvesting native run wild salmon just as free range ranching of cattle bears no relationship to harvesting animals from the existing wild populations. The problem is that the addition of so many animals to the existing food chain throws the ecosystem and the trophic equilibrium out of balance and affects food availability for the pre-existing wild populations of many different species. The effects aren't confined to salmon. The article can be found here:

http://www.vancouversun.com/life/Alaskan+practices+threaten+wild+salmon+conservationists/6001591/story.html

The other major flaw is that permission to expand farm operations is not predicated on available supply of or demand for salmon. Expansion is predicated on satisfaction of biological, ecological and environmental criteria as well as ensuring sharing of coastal resources among all user groups. If it was simply a question of meeting demand, the salmon farming companies would simply expand Chilean operations where the regulatory regime is much less strict and cost of operation is lower. Futhermore, any expansion of farm operations after extinguishing the commercial salmon fishery would be of great benefit to the province by replacing lost economic output.
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alwaysfishn

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #639 on: January 16, 2012, 01:21:44 PM »

I thought that what we are concerned with here is the best option for the fish. If we are going to shut down a sector, the best option for the fish is unquestionably putting a halt to the commercial harvest. It says something about your motivation that you would rather maintain that harvest and the harm it does the stocks simply to punish the farms.

Commercial harvest of wild stocks is considered sustainable and is managed to allow adequate escapement to ensure survival.  When there are low return years, minimal or no commercial fisheries are authorized.

The problems seem to lie in the survival of the fry when they migrate to the ocean. Eliminating the feedlot hazard is something that is controllable just like escapement numbers are. Unfortunately DFO's conflict of interest prevents it from getting rid of the net pens.
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Dave

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #640 on: January 16, 2012, 01:33:10 PM »

The public knows that Alaska salmon like BC wild salmon is not fattened up on synthetic feed pellets, antibiotics or dyes.
For the first year of their life and while growing out in net pens they are treated the same way as farmed Atlantics or our hatchery raised Pacifics, meaning antibiotics are used if necessary and the diet is identical.
I mentioned in an earlier post the amount of fungicide (formaldehyde marketed as "parasite S") is used in a small hatchery operation like the Cultus Lake sockeye program - the mind boggles at what amount Alaska uses.
But you nailed it af, it's public perception and marketing that runs this ship and I give full marks to Ms. Morton et al for beguiling so many people.
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chris gadsden

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #641 on: January 16, 2012, 01:38:07 PM »

Monday is here, I believe someone mentioned a while back I should post some info on the court case.

http://thecanadian.org/item/1278-salmon-activist-outpouring-public-cash-legal-battle-staniford-cermaq-mainstream-aquaculture

alwaysfishn

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #642 on: January 16, 2012, 02:03:20 PM »

Dave addresses one of the very real flaws in your argument. Regardless of the public perception of ranched Alaskan salmon, it bears no similarity to harvesting native run wild salmon just as free range ranching of cattle bears no relationship to harvesting animals from the existing wild populations. The problem is that the addition of so many animals to the existing food chain throws the ecosystem and the trophic equilibrium out of balance and affects food availability for the pre-existing wild populations of many different species. The effects aren't confined to salmon. The article can be found here:

http://www.vancouversun.com/life/Alaskan+practices+threaten+wild+salmon+conservationists/6001591/story.html


That's just a red herring argument with no basis in fact. It's often argued that hatchery salmon are less competitive than wild salmon because of their inferior genes. If that is true then it could be argued that wild salmon will out compete hatchery salmon. Therefore the Alaskan salmon should have minimal affect on the survival of BC wild salmon.

We should really be looking at the sustainability of fish farming as a whole. Apparently fish farms already consume more than 70% of the world's production of fish oil, with most of the balance being consumed by livestock and poultry. This is putting tremendous pressure on course fish in the ocean. If the fish farms continue raping the ocean this will effect the survival of the course fish as they are not be able to reproduce fast enough.

So i suggest that pointing a finger at the Alaskan way of doing things is pretty hypocritical. In the case of Alaskan salmon at least the released smolts are required to forage and their survival depends on their instincts for survival. In the case of fish farms they hire commercial fishermen to scrape the ocean destroying the eco system and killing everything in their nets in order to sell their catch to the farms which turn around and produce less than a kg of seafood for every 3 kg they scrape out of the ocean.

At least the wild salmon/Alaskan salmon has a respect for the ocean environment allowing it to produce food on a ecologically friendly and sustainable manner. Fish farming unlike livestock or poultry farming is not sustainable.
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alwaysfishn

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #643 on: January 16, 2012, 02:09:07 PM »

Monday is here, I believe someone mentioned a while back I should post some info on the court case.

http://thecanadian.org/item/1278-salmon-activist-outpouring-public-cash-legal-battle-staniford-cermaq-mainstream-aquaculture

My prediction is that Mainstream will drop the case pretty quickly. All this case is doing is giving Saniford another opportunity to air all of Mainstream's dirty laundry.
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absolon

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Re: Lethal virus from European salmon found in wild BC salmon
« Reply #644 on: January 16, 2012, 02:59:04 PM »

Commercial harvest of wild stocks is considered sustainable and is managed to allow adequate escapement to ensure survival.  When there are low return years, minimal or no commercial fisheries are authorized.

The problems seem to lie in the survival of the fry when they migrate to the ocean. Eliminating the feedlot hazard is something that is controllable just like escapement numbers are. Unfortunately DFO's conflict of interest prevents it from getting rid of the net pens.

Escapements are calculated by a predictive model and it isn't until after the harvest that true returns become known. It is too late to let more fish go should, as often happens, the returns be lower than predicted. There is also the problem of mixed strains returning at the same time. Strains at severe risk are mixed in with stocks that are stable; the harvest of those stable stocks also harvests the few remaining numbers of strains at risk. Little by little, strains disappear and the stocks become reliant on fewer and fewer sources and narrower and narrower genetic libraries. The abundant coho and spring runs of the sixties and early seventies have been reduced to fractions of their former glory by harvesting by these so-called sustainable fisheries.

Canceling the fishery entirely or putting in place a multi-generation moratorium would result in an abundant return for all remaining strains and ensure maximum reproduction to facilitate rebuilding the runs, maximum return of nutrients to river ecosystems and a substantial safety margin of seaward bound smolts to protect against natural variations in circumstances.

The problem appears to lie somewhere in the period of ocean residence, between outmigration and return migration. Ensuring that maximum numbers head to sea will also ensure that maximum possible returns return.

That's just a red herring argument with no basis in fact. It's often argued that hatchery salmon are less competitive than wild salmon because of their inferior genes. If that is true then it could be argued that wild salmon will out compete hatchery salmon. Therefore the Alaskan salmon should have minimal affect on the survival of BC wild salmon.

We should really be looking at the sustainability of fish farming as a whole. Apparently fish farms already consume more than 70% of the world's production of fish oil, with most of the balance being consumed by livestock and poultry. This is putting tremendous pressure on course fish in the ocean. If the fish farms continue raping the ocean this will effect the survival of the course fish as they are not be able to reproduce fast enough.

So i suggest that pointing a finger at the Alaskan way of doing things is pretty hypocritical. In the case of Alaskan salmon at least the released smolts are required to forage and their survival depends on their instincts for survival. In the case of fish farms they hire commercial fishermen to scrape the ocean destroying the eco system and killing everything in their nets in order to sell their catch to the farms which turn around and produce less than a kg of seafood for every 3 kg they scrape out of the ocean.

At least the wild salmon/Alaskan salmon has a respect for the ocean environment allowing it to produce food on a ecologically friendly and sustainable manner. Fish farming unlike livestock or poultry farming is not sustainable.

Just like a gang of midgets, 5 billion of them can knock the stuffing out of 100 million of bigger and stronger ones. The problem comes not from street fights between fish where winner takes all, it comes from predation on the food sources. The sheer numbers of the ranched fish can be in more places all the time and have consequent greater access and greater impact on the food chain. The food chain hasn't evolved to an equilibrium that supports the extra 5 billion. It currently balances in a range that matches natural numbers of wild fish, salmon and otherwise. The ocean isn't a limitless larder. The extra consumption overloads the supply and will eventually push demand to a point where the trophic web can't support it and permanent and irrevocable changes will take place. Once that happens, the web will restabilize at an equilibrium that will include considerably fewer predators at the trophic level salmon work at simply because there is not sufficient feed left to support them. Indeed, that may be the explanation for that at sea disappearance of wild stocks that we are currently experiencing.


It isn't accurate to suggest that in reality, 4 or 5 units of fish are really required to produce one unit of salmon; fish meal does not constitute 100% of the diet but rather closer to 30% with the rest being vegetable products. There is a fish oil component as well, but that is obtained in the meal production process from the same raw material that then becomes meal. Fish products are the most expensive component of fish feed, and though it is critical to the formulation in order to provide specific amino acids, it is of critical importance to the profitability of the industry to utilize the minimum amount that will meet the requirements of the salmon and much research is directed at developing alternate feed compositions that will further reduce that usage.

It also isn't accurate to suggest that fish meal production and fish harvesting has increased to accommodate aquaculture. In fact, world production has remained fairly steady and the percentage derived from waste products of wild fisheries for human consumption has increased steadily to the current level of about 25% suggesting fish harvests for the meal market are actually decreasing. The percentage of total production of fish meal used for all aquaculture, currently in the range of 60%, has increased while the percentage used in other animal feeds and for other purposes has correspondingly declined. Less than 20% of the proportion of the percentage of world supply that is used in the aquaculture sector actually goes into manufacturing salmon feed. There is no new production in order to accommodate salmon farming and there is no new environmental impact as a consequence of increasing salmon production and  those who suggest otherwise are misrepresenting reality.

Read more here:

http://www.iffo.net/downloads/Datasheets%20Publications%20SP/FMFOF2011.pdf

https://docs.google.com/viewer?a=v&q=cache:6kd_eFBlBU4J:www.aquafeed.com/documents/1230754702_1.pdf+fish+meal+production&hl=en&gl=ca&pid=bl&srcid=ADGEESi6gOpnt9Ow_8sFD9-2BvtGpojoo6FcGUkQsI2Qo3ewNr_d1lKysLTqZDtkZZ2dFMnQc_MBHNd952KfkvJcdta088_vNI4CM0d3N0YmLhi9wg8SaIVlbhKSgTGHA_KXTl7oc8Dg&sig=AHIEtbTRpHO9N2WqNvLImx0N0eiweDt6iQ
« Last Edit: January 16, 2012, 03:01:06 PM by absolon »
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