one sea louse, two sea lice, bled fish, dead fish…?

How does one discern between the two arguments?

Here are two headlines from the last two months on CBC’s website regarding open-pen salmon farms, sea lice and wild salmon:

Wild salmon sea lice linked to B.C. fish farms (Feb. 9, 2011)

Young sockeye salmon from B.C.’s Fraser watershed are infected with higher levels of sea lice after swimming past salmon farms, a new study has found.

And those salmon carry an “order of magnitude more” of the parasites than salmon that don’t swim past salmon farms, said a study published in PloS One this week.

Pacific salmon not affected by lice: study (Dec. 13, 2010)

The decline in wild Pacific salmon populations is not likely caused by sea lice acquired from farmed salmon, a study released Monday suggests.

The findings of the study headed by Gary Marty, a professor at the University of California, suggest that the number of wild salmon that return to spawn in the fall can predict the number of sea lice that will be found on farmed salmon the following spring, which, in turn, predicts the extent of sea lice infestations in young wild salmon.

_ _ _ _ _ _

Is the general public to believe then that between Dec. 2010 and Feb. 2011 that sea lice have gone from largely benign little critters to voracious consumers and salmon killers?

Whose “science” is more right?

Or, should the general public believe a $1.5 million industry-funded campaign by salmon farmers looking to protect their industry from public backlash?

Or, should the public believe the apparent conspiracy theorists that suggest most U.S.-based philanthropic organizations have an organized campaign of US-protectionism?

Will the quasi-legal Cohen Commission solve this issue once and for all — the Commission to end all salmon Commissions? (I do wonder when that’s all over if Justice Cohen will just shudder at the word “salmon”?)

Could the real story please stand up and reveal itself…

6 thoughts on “one sea louse, two sea lice, bled fish, dead fish…?

  1. Brian

    The Coastal Alliance for Aquaculture Reform needed to get something out quick to counter the Marty paper released in December. It is not a coincidence that Craig Orr and fellow co-authors released another report on wild salmon linked to sea lice. However, if you look carefully at each of the reports done scientists such as Morton, Krkosek, Orr, Reynolds, Price, etc…they do not really tell much more then the next. It is still not clear what the result is of these infections is. Ok, so there are sea lice on these fish, but is that the cause of massive mortality or the mortality of a small percentage that were already vulnerable due to being compromised already? Critics have not been able to clearly demonstrate this. There were no diagnotic tests done to fish from previous studies to see if some pathogen was involved or any determination for cause of death. This was a major flaw in Morton’s work in my opinion. When you sample fish from the wild how do you know that the fish you are sampling is not sick to begin with. That is the reason for controlled experiments in a lab. Lab experiments do have their disadvantages, but in a lab setting researchers can watch the juvenile fish for a period of time to see how healthy they are to begin with. Despite these shortcomings, Morton and fellow collegues seem fit to condemn the industry which is not logical based on what they have been able to prove. Correlation does not prove causation. This is an important point that gets overlooked by critics.

    I realize that replication of the same sort of studies can be seen as reinforcing the fact their is a problem with fish farms and sea lice. However, the way I see it is that these studies basically circle the barn, but do not find out what is going on inside. Marty et. al 2010 does not dispute the hypothesis or claims that farm salmon are a main source of sea lice infesting juvenile pink salmon. Marty et. al 2010 also does not dispute the claims by fish farm critics that sea lice can cause mortality, but when you factor in that size can play a role (some studies demonstrate that mortality is primarily limited to heavily infested fish smaller than 0.7 grams) the percentage that can die from sea lice may be much smaller. Pink salmon travel immediately to the ocean following emergence, so they are very small in the beginning. However, pink salmon are grow faster than other Pacific Salmon species, so this has to be considered also. Fraser River sockeye smolts are much, much larger than 0.7 grams once they enter the ocean. This also has to be considered. Pink salmon in the Broughton area were predicted to be extinct in 4 generations; however, the author of that 2007 report that predicted “local extinction” now concedes that this is no longer the case. In fact, pink salmon remain very cyclical – even before fish farms. Modelling is not a particularly bad thing, but sometimes you have to ground-truth your model with with the fish are actually doing. In this case how can anyone come to rational conclusion that pink salmon in the Broughton are becoming extinct?

    In the case of Fraser Sockeye, well….Morton predicted the collapse of the outmigrants from 2008 due to sea lice. From one of her media releases it was a pretty simple thing – sockeye juveniles get lice on them and they die. In 2010, we saw the result of those predictions. One thing I have learned this year is that the Fraser River Sockeye are predictably unpredictable. These outmigrants from from 2008 swam by these fish farms. I find it kind of funny that Morton explained this 2010 return was due to fish farms cleaning up their act; however, this was never mentioned in 2008 during her predictions. The fact is that fish farms practices did not change significantly between 2008 and 2010. Farms already use fallowing and SLICE in feed when required. When you have this variability going on it is reasonable to think that their are more important drivers out there than sea lice. Sea lice may work in connection with some other synergist to cause mortality and without it the mortality is not as bad. Perhaps is a combination of more than one factor and sea lice are just a minor blimp on the screen. It should be noted that Marty et. al 2010 used fish farm data to show that pink salmon productivity was consistently associated with sea lice numbers.

    Unfortunately, the public is caught between both sides making their case. I think what the public needs to get actively involved in reading these reports and not just posts from bloggers or reports from journalists. The internet can be a great resource but there are also some bogus stuff on the net as well. They also should keep an open mind as to all factors that can play a role in the life a salmon.

  2. Will

    Price et al. 2011 was not a quick CAAR reply to Marty et a.l 2010. The paper was based on research using samples collected in 2007 & 2008 and analyzed subsequently. The paper was submitted to PLoS One in Sept. 2010 long before Marty et al. 2010 was published.
    As Price himself said, “Like most scientific research, ours generates more questions than answers.” I’ll leave the scientific debate to the scientists. I’m sure there will be ample discussion of this new peer reviewed paper and much, much more when the lawyers at the Cohen Commission get around to the role of aquaculture in the decline of FR sockeye.
    In the meantime, you and your readers might be interested in this invited piece on the farmed/wild salmon debate and the role of science in that debate by Stephen Bocking at the U of Toronto; http://people.trentu.ca/sbocking/files/Bocking/BockingSG.pdf. Enjoy.

  3. joe

    Will, good article, thank you for the link. Years ago Yves Bastien spoke , in regards to aquaculture, “Let’s just do it”. Unfortunately, it seems the wild salmon and the marine environment are paying the price of such recklessness.

  4. Brian

    The paper by Mr. Bocking appears kind of outdated and inaccurate. It totally ignores any of the improvements and innovations the salmon farm industry in BC have done in the last 10 years such as fallowing, video monitoring of fish food to reduce the amount that does not get used, as well as the regulations and monitoring that the industry in BC has to endure. It also does not mention that DFO has taken on the role as the regulator for fish farms in BC. In addition, he fails to mention that Atlantics cannot breed with with Pacific Salmon (although it was tried and it failed). Mr. Bocking does not seem to know much about SLICE or antibiotics used by the industry and how often they are used. He also totally ignores what is going on with the pink salmon in the Broughton area and their cyclical patterns. I wish he could provide some documentation of these drownings of “sea lions in large numbers”. I love the internet….lol. Perhaps Mr. Bocking should come out to the BC Coast one day and visit a fish farm then go back to his university. Thanks for the read.

  5. Brian

    Here is something I posted before that sort puts things into perspective. The scientists and researchers that took part in this exercise are all highly respected in their fields. Basically they say, “Look, this is what we know right now, here are some other factors, and this is where we need more information.”

    http://www.psc.org/pubs/FraserSockeyeDeclineWorkshopReport.pdf

    As you will find out marine and freshwater pathogens are classified as possible to very likely contributing factors by the panel, but gaps still remain. I realize that critics would like to bypass this and go straight having the industry go to closed containment because it is something we can do right now as apposed to global warming.

    All human activity has negative effects to varying degree. If we are going to start using this same logic (i.e. moving the industry to closed containment on what we know so far..gaps and all) then to be fair we should also be extending the same logic at eliminating some of the other common human activities that also have varying degrees of impact on Pacific Salmon. Because really….what makes us think that our other activities have less or no impact when compared to fish farms? Similar to what I was talking about with regards to sewage, the public for the most part is adverse to change and would rather have big, bad industry do the changing. Perception plays a big part in this.

    Bocking talks about toxic contaminants coming from fish farms that cover the area of Stanley Park; however, what about all the contaminants that spill out into the Lower Fraser River daily from our treatment plants, boats and storm drains – into estuaries and into the ocean? In addition, there are landowners that have lakefront property in the interior of BC who remove gravel and cobble from the shorline in front of their cottages so that they can have a nice sandy beach. Little do they understand that sockeye are also lake spawners that will likely spawn in those areas – especially when there is “no room at the Inn”. As indicated in the report, 50% of the total life cycle mortality occurs in natal spawning and rearing areas. That is not insignificant even though it did not rate as highly by researchers as a major cause in declining production. I would not be surprised that these same cottage owners are stauch opponents to fish farms. The reality is that we like to point fingers at what we consider are the “high profile” offenders. Really we should be looking at the mirror and we will see the biggest offender with global warming as the legacy that keeps on giving.

    Thanks for the discussion.

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