What’s destabilizing B.C.’s wild salmon stocks?

Discussion in 'Conservation, Fishery Politics and Management.' started by Birdsnest, Dec 30, 2017.

  1. Birdsnest

    Birdsnest Well-Known Member

    In 2007, a study published in Science magazine made an ominous prediction: Broughton Archipelago pink salmon stocks faced extinction by 2015, as a result of sea lice from area fish farms infecting wild salmon stocks....
    But wild pink salmon stocks in the Broughton Archipelago didn’t collapse – they surged dramatically in 2014. And in 2010, Fraser River sockeye made a stunning comeback, with a return of 28 million fish, followed four years later with a return of 19 million...

    https://www.biv.com/article/2017/5/whats-destabilizing-bcs-wild-salmon-stocks/
     
    bones likes this.
  2. bones

    bones Well-Known Member

    But historical catch and escapement data illustrates that wild salmon numbers have plummeted before, only to rebound. In 1960, for example, pink salmon escapement numbers for Area 12 were even lower than in 2000 – long before there were any fish farms in B.C.

    Peterman studied sockeye productivity in more than 60 river and lake systems, ranging from Washington state to western Alaska. (Productivity is a measure of the number of adults produced per spawner.) He found that a 15-year general decline in sockeye productivity was not unique to the Fraser River. Sockeye in other river systems, including in Washington state and Alaska, where there are no fish farms, had similar productivity declines.

    “If you believe that climate change is having a negative impact on these stocks, which includes most scientists, then we will likely see additional declines in the future,” Noakes said. “Some stocks may even disappear particularly those in the interior of B.C.”
     
  3. Birdsnest

    Birdsnest Well-Known Member

    Thats right. There are just to many salmon declines up and down or coast many of which have nothing to do with salmon farms to insinuate large losses of wild salmon from salmon farming in bc.
     
  4. terrin

    terrin Well-Known Member

    Well for starters lets agree to just begin dealing with the ones that have something to do with salmon farms as your post acknowledges.
     
  5. Birdsnest

    Birdsnest Well-Known Member

    I think your missing my point. My point is overall there has been equal salmon declines in areas with and without salmon farms.
     
  6. agentaqua

    agentaqua Well-Known Member

    I think the caveat that the authors added was: "If outbreaks continue..." - something that I have not yet seen the pro-FF lobby acknowledge. That or that FFs were forced into treating their stock at predetermined lice levels by the BC government. Here is the article:

    http://science.sciencemag.org/content/318/5857/1772
    Declining Wild Salmon Populations in Relation to Parasites from Farm Salmon
    Martin Krkošek,1,2† Jennifer S. Ford,3 Alexandra Morton,4 Subhash Lele,1Ransom A. Myers,3* Mark A. Lewis1,2
    ABSTRACT
    Rather than benefiting wild fish, industrial aquaculture may contribute to declines in ocean fisheries and ecosystems. Farm salmon are commonly infected with salmon lice (Lepeophtheirus salmonis), which are native ectoparasitic copepods. We show that recurrent louse infestations of wild juvenile pink salmon (Oncorhynchus gorbuscha), all associated with salmon farms, have depressed wild pink salmon populations and placed them on a trajectory toward rapid local extinction. The louse-induced mortality of pink salmon is commonly over 80% and exceeds previous fishing mortality. If outbreaks continue, then local extinction is certain, and a 99% collapse in pink salmon population abundance is expected in four salmon generations. These results suggest that salmon farms can cause parasite outbreaks that erode the capacity of a coastal ecosystem to support wild salmon populations.

    There there was a peer-reviewed critique by Riddell et. al posted at:
    http://science.sciencemag.org/content/322/5909/1790.2.full

    and a rebuttal at:
    http://science.sciencemag.org/content/322/5909/1790.3.full
    http://science.sciencemag.org/content/318/5857/1772/tab-e-letters

    Worth reading the entire debate for those actually interested in getting past the headlines.

    In addition - this one:
    http://www.pnas.org/content/108/35/14700.full
     
  7. agentaqua

    agentaqua Well-Known Member

    Not sure about the "equal" part. Think I'd like to see some data for that claim.

    In addition - sea lice are not the only potential impact.

    How do you explain that the River's Inlet/Oweekeno stocks (where there are no FFs) have been found with European/Norwegian ISAv and PRV? Can the FF industry claim that these diseases had no impacts?
     
  8. wildmanyeah

    wildmanyeah Well-Known Member

    AA i think the water is a bit muddy on this topic as there has been numerous posts by anti FF on here that that stocks have to be really close to fish farms to have any impact. This was illustrated by the distance between the cook fish farm and Cowichan river. Where anti fish farm posters on here claimed that it was far enough away not to have an impact.

    Now you are saying that fish farms thousands of KM away are having an impact. So what is it? were those original claims by anti fish farm people on here wrong? and if so why did you not call them out as you were part of the thread?
     
  9. Birdsnest

    Birdsnest Well-Known Member

    Well I guess I will be forced to repeat my assertion that ISAv is not found in bc and you agent will have to take it up with Millar-Saunders who we all understand everyone here thoroughly respects.

    If you got to the 33:50 part if this video of KMS speaking very recently in Tofino you will here her clearly state “ISAv has not been found in British Columbia”. I know you have seen this statement from her once already as I just recently posted it for you and GLG on the CFIA Fired thread of yours which turns out is false accusation as well.
    Start at 33:50:


    If you go to this video, again of our highly respected scientist KMS you will here her eco my comment as quoted above. In the video where she states “ there are way to many declines that have nothing to do with aquaculture”
    Start at: 03:57



    Since your such a huge fan of KMS Ill let her answer your other question about prv and heck, lets throw in sea lice as well while we are at it.
    Start at 03:00.


    Her comments on this question would bring me right back to here opinion stated at 4:00 where she clearly states that “there are way to many declines that have nothing to do with aquaculture” then she goes on to say regardless the work is underway.



     
    Last edited: Jan 4, 2018
    shuswap and wildmanyeah like this.
  10. agentaqua

    agentaqua Well-Known Member

    Speaking of "muddy" - thanks for your last post. I guess you wish to avoid answering the question, then? No real defense for those data, eh?
     
  11. agentaqua

    agentaqua Well-Known Member

    Yes, BN - and I'll repeat again that both ISAv and PRv have been found in Oweekeno/River's inlet stocks. There are numerous lab results confirming that - even if you choose to ignore those lab results. I certainly can understand why a person who wishes that the open net-cage industry was exonerated would want those results to disappear. It's pretty damning that Norwegian/European diseases were introduced into naive, wild stocks.
     
    Last edited: Jan 4, 2018
  12. Dave

    Dave Well-Known Member

    Well aa, apparently KMS is also ignoring "those" lab results. So, are you saying she is wrong?
     
  13. agentaqua

    agentaqua Well-Known Member

    The available, online ISAv results have been posted numerous times on numerous threads and include numerous test results from numerous places in BC.

    What is in question is not the genetic source of the disease-vector (European/Norwegian), nor that they found ISAv in the test samples - but rather - if the tests could be confirmed using tissue culture (problematic - esp. for ISAv variants) - and what constitutes a "weak" verses a "false" positive using CFIA's methodology. CFIA uses an arbitrary and inappropriate cut-off as number of cycles of PCR amplification that works well for FF couch potatoes and the high titre level that they can carry and still be fed and protected from predators - very much unlike the wild fish - and what then should be the CT number for wild samples? That's the debate.

    However, since this has drastic trade implications for the open net-cage industry - and CFIA has convinced itself that it's primary job should be protecting trade & "winning the PR battle"- rather than the wild stocks - and ISAv is under CFIAs purview - they get to seize samples and shut down labs & issue speaking notes for ministers using script writers. Situation resolved.

    That also works for the FF supporters - and they are also much happier if we don't have this discussion over ISAv - and this all magically and quietly goes away - which it hasn't.

    As I explained previously on another thread - highly virulent diseases - and most introduced diseases start out that way - are a 2-edged sword. Bad for the host - but good that the host dies quickly before it gets a chance to spread the disease vector among high numbers of other uninfected hosts.

    I used the analogy of chimney sparks hitting wet grass. Burns out quickly. It remains yet to be seen if ISAv will indeed die-out - or - as many viruses do - morph into a less virulent disease-causing organism. I guess - we will see how that goes - whether we want to or even agreed to this open experiment over the next few years.

    As far as PRv goes - I would point you to the test results in the supporting information for the latest PRv article in PLOS1 at: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0188793#sec015

    Look at the Table S1 - Oweekeno Lake salmonid samples - where 2.3 - 10.5% of the samples tested positive for the European PRv. The question now is what population-level effect is that introduced PRv having on the wild stocks?
     
    Last edited: Jan 6, 2018
  14. Birdsnest

    Birdsnest Well-Known Member

    Im repeating this information again for you agent. PRV has been found in bc as far back as 1977 long before any salmon farm.
    Salmonid tissues tested for PRV by real-time rRT-PCR included sections from archived paraffin blocks from 1974 to 2008 (n = 363) and fresh-frozen hearts from 2013 (n = 916). The earliest PRV-positive sample was from a wild-source steelhead trout, Oncorhynchus mykiss (Walbaum), from 1977.
    http://onlinelibrary.wiley.com/doi/10.1111/jfd.12285/abstract

    And one more time, PRV is not genetically identical to any other strains known.
    Genomic sequencing of PRV from BC has revealed some genetic differences when compared to PRV from other regions (Kibenge et al. 2013). Based on an analysis of these genetic differences, these authors proposed that PRV first arrived in BC from Norway sometime around 2007. However, recent testing of archived samples held by DFO has revealed that PRV has been present in salmonids on the Pacific coast of North America for a much longer time than reported in that paper (Marty et al. 2015; Siah et al. 2015).
    Detections have been made from both farmed and wild fish populations which have extended from the state of Washington north through BC to Alaska


    http://www.dfo-mpo.gc.ca/science/aah-saa/species-especes/aq-health-sante/prv-rp-eng.html
     
  15. Birdsnest

    Birdsnest Well-Known Member

    Just recently on another thread you hold the US F&W in the highest regard for "firing" the CFIA yet the US F&W has not found ISAv is Oregon, Washington or Alaska either.


    From your thread:
     
  16. Dave

    Dave Well-Known Member

    Again aa, why would KMS say they have not found ISA? I suggest a scientist of her stature, and in her position, would not have answered in such a firm manner if she was not confident of her answer. If she was the least bit concerned about this virus she would have hedged her response.
     
  17. Floater

    Floater Well-Known Member

    I sense an unraveling.
     
  18. Birdsnest

    Birdsnest Well-Known Member

    Agent, Are you calling Millar-Saunders a liar?
    20116944213_645eab720b_o.jpg
     
  19. GLG

    GLG Well-Known Member

    Why not be honest with your arguments? I showed you the migration data from the Cowichan when you made that claim. Cowichan have had extensive study over the last few years as part of the marine survival program. We know where they go but for some reason you refuse to accept that. I can only conclude that you are here not for what's best for our salmon.
     
  20. wildmanyeah

    wildmanyeah Well-Known Member

    Well clear it up for us then are Cowichan chinooks effected by fish farms or not?
     

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