Results 1 to 8 of 8

Thread: Offshore test index for Cook Inlet Sockeye

  1. #1
    Member
    Join Date
    Apr 2008
    Posts
    2,448

    Default Offshore test index for Cook Inlet Sockeye

    I heard the recording and the OTI numbers were in the single digits. Thats insane this time of year is it not? I sure hope we see a big jump soon. Am i correct in thinking they were higher this time last year and the year before? Did Bristol Bay ever pick up with the Sockeye fishery? I heard they were off to a rocky start

  2. #2

    Default

    Index points are extremely low so far. So are drift fleet harvests.Many think (or hope) that increased water temps have the fish lower in the water column and thus uncatchable with a gillnet. And the bay has downsized the forecast from the high 40s to the 30s (millions).hopefully Nerka will comment on the first theory.
    Last edited by gunner; 07-07-2015 at 11:24. Reason: spelling

  3. #3
    Member
    Join Date
    Feb 2015
    Location
    Alaska
    Posts
    384

    Default

    Quote Originally Posted by gunner View Post
    Index points are extremely low so far. So are drift fleet harvests.Many think (or hope) that increased water temps have the fish lower in the water column and thus uncatchable with a gillnet. And the bay has downsized the forecast from the high 40s to the 30s (millions).hopefully Nerka will comment on the first theory.
    When we are told they are late, it is soon followed by " the run is not as strong as forecast" and they are not coming. It would be more honest for the Dept to call it like it is, a 'guess'. When it is 40% off one side or another as it often is, what good is it. I am sure that, given the inaccuracy of these guesses, industry does its own forecasting in deciding how to proceed in any given year. The little guys, however may depend on these Dept numbers in making purchasing and other important decisions. Sometime to their detriment, regrettably.

  4. #4

    Default

    Quote Originally Posted by Questairtoo View Post
    When we are told they are late, it is soon followed by " the run is not as strong as forecast" and they are not coming. It would be more honest for the Dept to call it like it is, a 'guess'. When it is 40% off one side or another as it often is, what good is it. I am sure that, given the inaccuracy of these guesses, industry does its own forecasting in deciding how to proceed in any given year. The little guys, however may depend on these Dept numbers in making purchasing and other important decisions. Sometime to their detriment, regrettably.
    Wow, a lot of negativity in that post.

    Sockeye forecast numbers for Kenai/Kasilof have been remarkably accurate in the past, given the difficulty of this type of thing. I think I looked a year or two ago and their error was about 30% but Nerka will know this I think. Strong late runs have happened in the not-too distant past. Over 1 million Sockeye entered the Kenai in August just a few years ago.

    Warmer water temps = smaller fish, and often, later runs according to ADFG. I guess maybe they stay out longer trying to gain weight?

  5. #5
    Member
    Join Date
    Jul 2006
    Posts
    5,534

    Default

    Quote Originally Posted by Questairtoo View Post
    When we are told they are late, it is soon followed by " the run is not as strong as forecast" and they are not coming. It would be more honest for the Dept to call it like it is, a 'guess'. When it is 40% off one side or another as it often is, what good is it. I am sure that, given the inaccuracy of these guesses, industry does its own forecasting in deciding how to proceed in any given year. The little guys, however may depend on these Dept numbers in making purchasing and other important decisions. Sometime to their detriment, regrettably.
    Questairtoo - you are really off base on this one. First the error you report is not accurate. The test fish program is much better than that and usually the error is to underestimate the run not overestimate it. That is because late large runs are not picked up by the models. Extremely early runs have a similar problem but over all the error is around 20% and much better on mid level returns.

    Next, the program is not designed to be used the way people are using it. For example this discussion. Anyone making a projection on July 6th from the test fish program has no idea how it works. When I designed the program the first estimate we made was after July 10th and the best fit estimate rarely maintained throughout the season. Usually the second or third best fit turned out correct. So after three decades of doing this managers factor this in to decision making.

    The program is being used by ADF&G leadership and the public incorrectly. Since I developed the program I have some justification in saying this. The program is designed to tell managers if the total return is plus or minus one million fish. So an estimate of 3 million could be 2-4 million. That information is good mid -season for decision making and meets the precision requirements for management. However, by the third or fourth week of July management decisions should be based on escapement levels. Unfortunately, with the new plans with all the limitations managers are pushing this program to do more than it can. For example, I have heard people say there is 800,000 fish out in the inlet yet to harvest and then they do not show up. That is because at the end of the season one can get high indexes that do not translate to fish. It is not to be used for this type of decision making. I would bet most people do not understand at all how the program works. Just to help here the program is based on the indexes and what the passage rate is for fish entering the district. That means the passage rate changes during the season and so 100 index points early in the season does not mean the same as 100 index points late in the season. Estimates of passage rate are made from commercial catch, sport catch, PU harvest, and escapement.

    At this point the returns to the Bay are down and to PWS. However, those returns rarely correlate with UCI so at this point in the season I would just give it some time to develop. No reason to get upset until around the 15th of July.

  6. #6
    Member
    Join Date
    Feb 2015
    Location
    Alaska
    Posts
    384

    Default

    Quote Originally Posted by Nerka View Post
    Questairtoo - you are really off base on this one. First the error you report is not accurate. The test fish program is much better than that and usually the error is to underestimate the run not overestimate it. That is because late large runs are not picked up by the models. Extremely early runs have a similar problem but over all the error is around 20% and much better on mid level returns.

    Next, the program is not designed to be used the way people are using it. For example this discussion. Anyone making a projection on July 6th from the test fish program has no idea how it works. When I designed the program the first estimate we made was after July 10th and the best fit estimate rarely maintained throughout the season. Usually the second or third best fit turned out correct. So after three decades of doing this managers factor this in to decision making.

    The program is being used by ADF&G leadership and the public incorrectly. Since I developed the program I have some justification in saying this. The program is designed to tell managers if the total return is plus or minus one million fish. So an estimate of 3 million could be 2-4 million. That information is good mid -season for decision making and meets the precision requirements for management. However, by the third or fourth week of July management decisions should be based on escapement levels. Unfortunately, with the new plans with all the limitations managers are pushing this program to do more than it can. For example, I have heard people say there is 800,000 fish out in the inlet yet to harvest and then they do not show up. That is because at the end of the season one can get high indexes that do not translate to fish. It is not to be used for this type of decision making. I would bet most people do not understand at all how the program works. Just to help here the program is based on the indexes and what the passage rate is for fish entering the district. That means the passage rate changes during the season and so 100 index points early in the season does not mean the same as 100 index points late in the season. Estimates of passage rate are made from commercial catch, sport catch, PU harvest, and escapement.

    At this point the returns to the Bay are down and to PWS. However, those returns rarely correlate with UCI so at this point in the season I would just give it some time to develop. No reason to get upset until around the 15th of July.
    my numbers were meant to apply to the Bay. The Dept has been way off on many occasions. Last year and now it appears this year. Unless??? My opinion could also apply to some aspects of the UCI. Chinook forecasts have been pretty far off in recent years as you know. My point is that everyone who depends on a preseason forecast by making important investment decisions is taking a very real risk. It has nothing to with being negativity as King Roller would like claim. And hoping they are late, deeper, etc is ok I suppose if it provides solace. But if I were in the Bay I would recognize the error and regret it if I madexsignificant changes based on these guesses.

  7. #7
    Member
    Join Date
    Feb 2015
    Location
    Alaska
    Posts
    384

    Default

    Nerka: my post was intended to refer only to pre season forecasts and not in season projections.

  8. #8
    Member
    Join Date
    Jul 2006
    Posts
    5,534

    Default

    Quote Originally Posted by Questairtoo View Post
    Nerka: my post was intended to refer only to pre season forecasts and not in season projections.
    Great, I thought you were talking about the OTF for UCI since that was the thread title.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •