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.
You suggested that we do not need to be worried about the fish farms because their "best practice"
already minimizes their impact on wild fish, and I asked, if that is true, why did the government have to issue an
Order to get them to fallow during out migrations of wild salmon? Just answer the question.
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.
No, it sounds quite clearly that they are absolving the farms of even contributing to higher lice populations. I was just wondering aloud.
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.
So a wild salmon can get close enough long enough to the pens to pass pathogens to the farmed fish but other wild salmon cannot get close enough long enough to have the same pathogen passed back once it has grown and multiplied in the confines of the farm? Seems strange. I wonder if anyone has done a scientific study to prove that?
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.
I understand that under normal conditions, that wild fish might have a strong enough immune system to combat the infection, but in the scenario I proposed, the wild fish would be returning to a nearby stream to spawn where its own immune system would be undermined by the stress of spawning and it would be in close proximity to large numbers of other fish so the likelihood of spreading the infection would indeed be high. This happens all the time already from those "natural" pathogens. However, this pathogen would also not be the same one it was exposed to in the wild as the bacteria have be exposed to antibacterials and so the wild fish is infected with the biggest and baddest of the bacteria that did not get killed off by the antibiotics. The wild fishes immune system is going to have a harder time combating that infection so the risk of infection is indeed there. This really does not seem as far fetched as you imply.
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 thought "the world doesn't owe you anything." A simple search on Google of the reference citation would have turned up this paper: Pål Arne Bjørn, Rolf Sivertsgård, Bengt Finstad, Rune Nilsen, Rosa Maria Serra-Llinares, and Roar Kristoffersen, "Area protection may reduce salmon louse infection risk to wild salmonids,"
AQUACULTURE ENVIRONMENT INTERACTIONS, Vol. 1, May 30, 2011, pp. 233–244, 2011. Stop being hypocritical. This is a blog anyway and is not supposed to be a peer reviewed article. If I need to provide a bibliography every time I post then so do you. No wonder why no one else bothers to post.
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.
Thank you, that was what I wanted five or six posts ago. It is clear that we are arguing cross purposes then, as I am
not arguing that they are
the cause for the decline, but are a contributing factor, putting additional stresses on the environment and the fish that live in it. We can stop arguing now.
The history of the industry in the province has shown that it does not cause the catastrophic damage the reactionaries accuse it of.
No, the history does not show that, the history shows that is causing damage and that the damage is being "managed." The "catastrophic" damage has not yet been proven conclusively, but then there has not been nearly enough research into the effects of farms here (most of the research of the effects of open pens on the environment and the wild fish has been done in other parts of the world, and as you point out, the conditions here are different enough that studies need to be done here to be really helpful), and the research that has been done here is being called into question instead of being corroborated. You just keep your fingers crossed for both of us.
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.
I have done so. Your criticism is over my inclusion of arguments that point to
potential dangers that have not yet materialized, and until they do, the "reactionaries" will not have those "facts" (in the form of documented scientific evidence), unfortunately by the time they have that evidence, many fear it will be too late anyway. I am still waiting to see those scientific studies that show that farmed Atlantic salmon
cannot pass pathogens to wild Pacific salmon. Surely, if I need to provide proof it
can happen, then you need to prove that it
cannot. Simply pointing to the fact that no disease has been found yet in the wild fish surveyed, is not proof, especially when it
has been found, but all the energy is directed toward showing that it really had not been found at all.
If you want to do something constructive for the wild stocks, you should be supporting the elimination of the commercial salmon fishery.
You would like that wouldn't you? Eliminate the only other source of salmon so the farmers can say "Now you do NEED us!" I have been interested in Commercial fishery reform since the 90s when I wrote an undergraduate paper on the state of the commercial fishery following the Cruikshank Report. I never said I supported salmon ranching any more than salmon farming. The salmon ranching just uses a larger pen (the entire ocean) and relies on nature to raise the fish to harvest once it reaches a suitable size. The issues are different, but no less troubling than the open pen farms. As a sport fisher I am also intimately aware of my own impact on the salmon and have been involved in various reform initiatives of the sport sector such as quota reductions (eg: annual limit of 20 coho, and lower daily limits of various species), and do not get me started on hatchery programs. Neither of these, however, are the topic here, which is possibility of the spread of disease to wild fish from open net pens (and I do apologize to AF for hijacking the topic). You guys may get back to it.
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Topic: Lethal virus from European salmon found in wild BC salmon (Read 290940 times)