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Kenai Sockeye Failure Discussion

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  • #16
    some answers

    The sonar counts in the oil spill year of 1987 and 1989 was about 1.6 million. In 1988 it was 1 million. The return from these years started the whole discussion of interaction between years. The return from 1987 was 9.5 million, from 1988 2.1 million, and 1989 3.6 million. Interestingly the 1987 record return came of 600,000 sonar counts. So biologist ask the question why the range and how does Skilak Lake produce sockeye?

    Here are some data from the simulation model that was developed from this work of what escapements can do. If you fixed the escapement at these levels this is what the model says about the probability of harvesting less than 1 million fish.

    At 500,000 to 800,000 spawners and a euphotic zone depth (EZD light penetration of 1% of surface) of 8 meters 5 percent of the time the return will bring a harvest of less than 1 million. At a EZD of 4 meters it is 20%. In contrast, at escapements of 1.5 million the probability of a harvest of less than 1 million is 90% if the EZD is 4 meters. If it 8 meters the probablity is still 60% that the harvest will be below 1 million. I think anyone can see why ADF&G is nervous about the glacial melt impacting Skilak Lake and the impact of large escapements.

    So even with escapements in the 500,000-800,000 range you have some poor years.

    Further data from the Kenai shows this. The best average return for the last 25 years of data come from escapements in the 500,000 to 800,000 range and that is why ADF&G set the biological escapement goal at this level.

    Hope this helps the discussion. All of these figures are in ADF&G reports. The best report is the final report to the EVOS council.


    • #17
      Thanks Nerka, very helpful. It looks like there is still a lot of work that needs to be done, this year, even though dismal, may give some good data for future management.


      • #18
        so now what..

        I was wondering what is the use of all the science if we have no idea how to use it? I have been quite impressed with Nerka's knowledge of the ecosystem but I have yet to see any real plan come from it. My question is can all the factors be controlled (my guess is no)? If they can not than what should we do, can we predict the turbidity or the EDZ, can we gauge the amount of food availible? Should the model be adjusted to account for factors like the one Nerka has laid out, is that even possible?

        I have been wondering for awhile and even asked, where you learned all this? Do you have formal training as a scientist because I'm very impressed with your knowledge. Send me a PM if you prefer.


        • #19
          plan of action

          First, in response to the request for information on my background. I tend not to answer those type of questions on the internet as a general security procedure. I will say I was trained as a scientist in the lower 48 and have a passion for sockeye salmon biology. Therefore, I read lots of reports.

          I am not trying to decieve anyone but I just do not like the internet because of the wide distribution. The other factor is that as a scientist I like to make arguements based on merit and rationale thoughts not authority of position. I hate it when a scientist say I know more than you because I am a scientist. It may give the individual more training, better tools to make his or her case, but just having a degree does not mean much to me. In addition,that way personalities and intimidation do not enter the discussion. We can evaluate each others comments in a more pure sense. Hope that helps answer your question.

          As far as a plan the Board of Fish in 1999 had a fairly good one which was altered in 2002 and 2005. Those changes made the plan fail. First, keeping the escapment levels between 500,000 and 800,000 in the long term will provide very high sustained yields with low chance of run failure. Second, we must live with the reduced turbidity so local governments, businesses, and the State should start to plan for the downturn in production if this continues. Third, the State should fund a significant program of monitoring Skilak,Kenai and Tustumena Lakes so that data are available for decision makers - whether this is to forecast the return or to better understand how sockeye salmon are produced. It may be that with the change in turbidity that other factors on production will become more or less significant. Finally, the Board of Fish needs to go back to 1999 plan and allow ADF&G more flexibility in managment. I firmly believe more chinook are being caught with the 2005 plan than the 1999 plan.


          • #20
            well said..

            Thanks Nerka, sounds solid. I'm sure Marcus can get you into contact with the right people, what am I saying, you already know how. Would you suggest any change to the goal 0f 500,000 to 800,000 fish considering the impact of water turbidty. Going back to the 1999 plan sounds good but if conditions are different now does it need to be adjusted? I'm assuming the change was made to satisfy the guides on the river, fell free to correct me on this if I'm wrong. One thing I do know, if we have a few years like this in a row heads will roll and the state will be forced to change policy. What was the count today?


            • #21
              The right people. . .

              Originally posted by SockeyOrange
              I'm sure Marcus can get you into contact with the right people, . . . Going back to the 1999 plan sounds good . . .
              SockeyOrange: If you'd like to submit a proposal to return to the 1999 plan at the next Board of Fisheries cycle for Cook Inlet, I'd be happy to steer you to the right people at ADF&G who can help you in writing and submitting it. Let me know if I can be of help. Glad to do it. . .


              • #22
                Loaded for bear..

                How serious does the board take proposals submitted by the public? Is it a common occurace (do they get flooded with them), have you ever submitted one? What was your experience with the process? Thanks for your help!


                • #23
                  Glad to help. . .

                  Originally posted by SockeyOrange
                  How serious does the board take proposals submitted by the public? Is it a common occurace (do they get flooded with them), have you ever submitted one? What was your experience with the process? Thanks for your help!
                  It's my understanding that BoF takes all proposals seriously and that many, many proposals come from the public. Have never submitted one myself so don't have any personal experience with that aspect of the process. However, I know many folks who have submitted proposals, and their opinion seems to be that Alaska's regulatory process is outstanding in its open-door policy to public input. Give it a try. If you tell us where you live, maybe someone on the forum could steer you to your area ADF&G Advisory Committee where you could get lots more information. Glad to help. . .


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