Sunday, September 8, 2013

Bycatch in pollock fishery 'seems unlikely' as cause of Chinook declines in AYK, research report says

An organization known as the Arctic-Yukon-Kuskokwim Sustainable Salmon Initiative recently issued a research action plan to address Western Alaska's weak Chinook returns.

The plan is cumbersome reading, but Deckboss spent some time with it and offers this very brief summary.

An "expert panel" co-chaired by Daniel Schindler, a University of Washington fisheries scientist, identifies seven hypotheses thought to be the most likely causes of low Chinook returns.

Out of these seven hypotheses, the expert panel gives six the highest priority for research funding.

The one not ranked highest priority is marine bycatch — the idea that mortality from non-salmon fisheries in the ocean has contributed to the decline of AYK Chinook stocks.

The action plan states:

Based on available data, the bycatch within the domestic walleye pollock fisheries seems unlikely to have been the primary cause for the recent dramatic declines of Chinook salmon in the AYK region, because estimates of bycatch from this source are not high relative to the estimated declines in the total returns to the drainages.

The other six hypotheses include: density-dependent effects and overcompensation; freshwater mortality; ocean mortality; anthropogenic changes to marine ecological processes; escapement quality; and pathogens.

Obviously some of these are a bit technical. But the action plan contains plenty of additional detail on each hypothesis.

9 comments:

  1. Hardly anybody who has read the reports, EIS/RIR's has argued that the pollock fishery is the "PRIMARY" cause. Those that do are misguided.

    However a bycatch spike (even within the parameters of the current caps/performance measures) at these currently low levels of abundance would have a very significant impact upon the ability to meet escapement goals and subsistence needs.

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  2. Re Anonymous at 9/8 10:11 - Don't pay attention to that man behind the curtain! It is far easier for some people who do not want to be burdened with unpleasant truths to point fingers at someone else as the culprit for all of their woes. It is wasted effort, however, to heap harm on the scapegoat in an effort to be seen as "doing something."

    Kudos to the Sustainable Salmon Initiative and their experts for focusing on the real difficult issues instead of taking cheap shots at innocent bystanders. Now, let's all roll up our sleeves and get to work.

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  3. The federal Environmental Impact Statements cited above calculated that the Bering Sea pollock fishery contributes less than 4% mortality of returning Chinook to AYK rivers and less than 1.5% of returning chum to AYK rivers. In other words, if the entire 1.2 million metric ton Bering Sea pollock fishery were eliminated, returning AYK Chinook would be expected to increase less than 4% and returning chum, increase less than 1.5 %. Because these numbers do not account for in-river fishery mortality, the contribution of actual fish to escapement would be even less. Nonetheless, conservation of these salmon should remain a high priority. The North Pacific Council and the State of Alaska have implemented measures that have significantly reduced bycatch of these species in the pollock fishery. Pollock fishery participants have supplemented those measures with costly time and area closures and the use of salmon excluder devices which allow salmon to excape from their nets. While bycatch has been reduced significantly, every fishermen knows it cannot be eliminated. As identified in the AYK Sustainable Salmon Initiative, it's time to identify research that will help us all better understand what contributes to the decline of the remaining 95%of AYK Chinook and chum runs.

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  4. The conclusion of this report assumes that the reported bycatch numbers are accurate.

    The historical bycatch numbers are very inaccurate, and NOAA knows this, and that is why individual bycatch numbers are State secrets.


    Even the decades of observer abuse and intimidation is kept as a secret.

    Rampant observer intimidation, well documented can have only one logical purpose, ... to hide the real bycatch numbers.

    The Bering Sea and North Pacific pollock fisheries were in essence a new salmon fishery, that was added to the existing full utilization of these Chinooks.

    Most of the observers and crews that witnessed these acts of hiding the real bycatch are still alive today, and if they ever start talking honestly, there will not be a person in this fishery, or NOAA/NMFS that will survive with a shred of credibility left to their name.

    The observors had to finally sue to get a partial disclosure of the fully reported and documented abuses that they suffered at the hands of the trawl industry, and if you read these reports which went to NOAA/NMFS, one cannot come away without being shocked, and knowing that the historical bycatch numbers are a fraud and the fraud is well known by all the direct participants in the industry, the managers of these companies, and sadly NOSS and NMFS.

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  5. 4.0 % of nothing is a big number when there is literally are no Chinooks in western Alaska! You can't see them if they are not there. If the entire 1.2 million metric ton Bering Sea pollock fishery were eliminated, returning AYK Chinook would be expected to increase less than 4%, at that rate how many years would it take to return Chinook populations to 100%. 7 years, maybe? Most likely many more than that. Salmon excluder devices which allow salmon to excape from trawl nets, just how many are scaled burn from the mesh? How many are consumed by predators lurking on the other side of the trawl? lots of question and so few answers. What do those Chinook feed on? Maybe pollack? I just know the talk in the Nushagak king fishery in the 80's was that those trawlers were catching those kings, back then there were 100,000 commercial catch. It's been quite a few years since Nushagak has had seasons like that. Maybe it's time for the Pollack fleet to sit on the beach?

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  6. @ 10:55 (Stephanie, Glen, or whoever you are) the stock impact estimates in the EIS/RIR assume far healthier stocks than we have today (that's the denominator in your harvest rate %'s...change that number and it changes the % significantly).

    The EIS/RIR also assumed a lower western AK stock contribution than more recent genetic studies seem to indicate.

    Lastly, it assumes a uniform impact across all stocks withinin the CWAK genetic stock grouping (which is sadly lacking further definition).

    Ass U Me?

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  7. For every salmon the observer sees, 4-5 more go over the side. That is whats expected by your deck boss on a pollock boat

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  8. Maybe it's the one thing that has changed the most over the past 15 years. Over sports fishing... Lodges everywhere with everyone catching and talking fish at a level that in prior years never happened. Look to what has changed the most. There are lodges on every river and game hogs in every creek..

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  9. Stats can be manipulated to reflect whatever you want to see...

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