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Thread: ADF&G refutes portions of chinook tagging study in UCI

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    Default ADF&G refutes portions of chinook tagging study in UCI

    http://www.animalbiotelemetry.com/co...015-0027-x.pdf


    I hope the above link works so one can read the whole article. The article title and abstract is below. This is pretty significant action on ADF&G part- Good for them to point out the obvious simplification in some of the conclusions.

    Oversimplification of complex harvest modelingissues outlined in Welch et al. (2014)

    In their paper, ‘Migration behavior of maturing sockeye (Oncorhynchus nerka) and Chinooksalmon (O. tshawytscha) in Cook Inlet, Alaska, and implications for management,’ Welch etal. (Anim. Biotelem. 2:18, 2014) report data on migratory behavior and relative swimmingdepths of Chinook and sockeye salmon near the Eastside Setnet (ESSN) fishery, Cook Inlet,Alaska, using acoustically tagged fish and an anchored array of acoustic receivers. Using thisinformation, they provide a model to estimate changes in Chinook and sockeye salmonharvests associated with potential regulatory changes affecting surface gillnet depths in thisfishery. We are concerned that the modeling exercise paints an unrealistic picture of howsimply changing gillnet dimensions would translate into a viable management approach topreserve or increase sockeye salmon harvests while minimizing catch of Chinook salmon.Much of this fishery occurs in very shallow water, and Cook Inlet tides range about 10 mwith tidal current speeds reaching about 9 km hr−1. Model assumptions that gillnets in thisdynamic environment were hanging vertically and that gillnets did not reach the bottom arenot valid. Gillnets in this fishery billow in strong currents causing the lead lines at the bottomof the nets to rise in the water column, and an unknown but high fraction of all gillnets reachthe bottom for some portion of each tide cycle. We believe further information and a moresophisticated analysis is needed to realistically model changes in Chinook and sockeyesalmon harvests in relation to gillnet depths, and we are concerned about unintendedconsequences that may arise from unrealistic solutions based on limited data proposed in theregulatory arena.K

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    Thanks for posting, Nerka. I think most people recognized that presentation for what it was. I'm glad to see the Dept. taking the time to scientifically refute that report for its simplicity and small data set. I suspect that a certain group might find themselves on the outside looking in if they burn too much capital on blocking Mr. Ruffner's nomination and the setnet ban initiative goes to the voters. Maybe Rome is finally going to fall.

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    Quote Originally Posted by Seinerman View Post
    Thanks for posting, Nerka. I think most people recognized that presentation for what it was. I'm glad to see the Dept. taking the time to scientifically refute that report for its simplicity and small data set. I suspect that a certain group might find themselves on the outside looking in if they burn too much capital on blocking Mr. Ruffner's nomination and the setnet ban initiative goes to the voters. Maybe Rome is finally going to fall.
    Many may have recognized this for what it was, but not all. Several BOF members thought was great, and were helping Welch lobby for funding to do more studies - not to mention they happily used it to pass restrictions on the ESSN fishery.

    From the report:

    "Developing the level of understanding of these processes necessary to accurately estimate harvest changes will be very costly and challenging. We are committed to providing the best information possible to the Alaska Board of Fisheries as they deliberate regulatory changes. However, we are also acutely aware of unintended consequences that may arise from unrealistic solutions based on limited data proposed in the regulatory arena."

    Thanks ADFG.

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    The Welch study indicates:

    1. Kings tend to migrate along the beach and mill for days before entering the rivers.
    2. Kings tend to travel deeper in the water column than sockeye where depth allows.

    None of the purported objections to the study design fundamentally change these findings.

    The implications of these findings are two-fold:

    A. King harvest/interception rates in the east side set net fishery may be substantially greater than recently estimated.
    B. Shallow mesh nets may confer some saving in king catch reduction relative to sockeye.

    These findings threaten many long established interests which are seeking to discredit the study.
    (And Nerka owes Mike Bethe an apology.)

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    Quote Originally Posted by Bfish View Post
    The Welch study indicates:

    1. Kings tend to migrate along the beach and mill for days before entering the rivers.
    2. Kings tend to travel deeper in the water column than sockeye where depth allows.

    None of the purported objections to the study design fundamentally change these findings.

    The implications of these findings are two-fold:

    A. King harvest/interception rates in the east side set net fishery may be substantially greater than recently estimated.
    B. Shallow mesh nets may confer some saving in king catch reduction relative to sockeye.

    These findings threaten many long established interests which are seeking to discredit the study.
    (And Nerka owes Mike Bethe an apology.)
    No I do not. The Bethe study and this one is flawed for a number of reasons. Your conclusions are just the opposite of what ADF&G is saying. First, you cannot say anything about how chinook move in UCI. The sample size and the representativeness of the fish tagged is in question. Tagging fish that are already on the beach and saying the population moves along the beach is nuts. Next, the sensors were not on the beach they were offshore a mile or more. Next the handful of fish says nothing about what the total population is doing and interception rates cannot be calculated. This study was flawed from the start and I am shocked you think it is worth something that can be used for management or conclusions about migration.


    Next, ADF&G points out that there are a number of variables that the conclusions failed to consider relative to sockeye and chinook management.

    Finally Bfish, if anyone can be charged with bias it is you and who you work for. ADF&G has got no skin in the game other than trying to point out the complex nature of the fishery and why simplistic comments and bad conclusions can lead to poor management actions. This study threaten no long standing interests which are seeking to discredit the study. The author of the study did that with making conclusions his data cannot support.

  6. #6

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    Quote Originally Posted by Bfish View Post
    The Welch study indicates:

    1. Kings tend to migrate along the beach and mill for days before entering the rivers.
    2. Kings tend to travel deeper in the water column than sockeye where depth allows.

    None of the purported objections to the study design fundamentally change these findings.

    The implications of these findings are two-fold:

    A. King harvest/interception rates in the east side set net fishery may be substantially greater than recently estimated.
    B. Shallow mesh nets may confer some saving in king catch reduction relative to sockeye.

    These findings threaten many long established interests which are seeking to discredit the study.
    (And Nerka owes Mike Bethe an apology.)
    In other words,

    The Welch study indicates:

    1. Something we already knew.
    2. Something we already knew.

    The implications of these findings are three-fold:

    A: The queen loves our money. All 900,000 loonies.
    B: Alaska should not depend on biolostute contractors to perform our fisheries research.
    C: KRSA and The Matsu Borough Fish and Wildlife Commission pay sketchy contractors to do their advising and research. No doubt the contractor (name starts with a B) they pay to do their "scientific" lobbying is slightly defensive over this study since he, by Mr. Welch's own admission, was the guy who put the interested parties in touch and got the ball rolling on the whole study and likely pushed it to its very political and sketchy conclusion.

    Bfish, you know as well as I that not all kings migrate up the beach. Likely, a large percentage of them exhibit their typical saltwater tendancies which are to stay in deeper water along structure lines, meaning that a substantial portion of Kings likely come up the inlet steep and deep along the shelf outside setnet gear. ESSN exploitation rates support this theory, and despite what you claim, there is no reason to believe the ESSN harvest rates are any less accurate than any other fishery. Unless you are claiming that we are less honest... that would be ironic.

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    Quote Originally Posted by Bfish View Post
    None of the purported objections to the study design fundamentally change these findings.

    The implications of these findings are two-fold:

    A. King harvest/interception rates in the east side set net fishery may be substantially greater than recently estimated.
    B. Shallow mesh nets may confer some saving in king catch reduction relative to sockeye.

    These findings threaten many long established interests which are seeking to discredit the study.
    (And Nerka owes Mike Bethe an apology.)
    You've got to be kidding, right?

    To say Welch's study was oversimplified is an understatement. Thank you ADF&G for calling them out.

    Migration depths for Kings are so variable once they hit CI and the ESSN area that it would be futile to make a conclusion like Welch did. Wind currents, wind direction, tide currents, wave height, wave direction, bottom depth, water clarity, run timing, and even sunlight all effect how deep the Kings run and how the nets fish. None of which were evaluated adequately, if at all.

    One thing's for sure...once all those Kings are in the River, sport fishermen catch almost all of them on the bottom. Maybe Bfish should promote a study with a different premise: conserving Kings by sportfishing the Kenai without jet planers, divers, weight, or diving plugs - cut their fishing depth in half too.

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    Besides the oversimplification, lack of data sets, failure to account for different variables, small sample size, and ineptitude in executing this "experiment", the assumption that a salmon would react normally after having a beer can size transmitter shoved up its ass is laughable. One of the salmon made a bee line thousands of miles away from the site of the sexual assault. The "other one" swam up and down the beach for two weeks without getting caught in a net. Two conclusions can be drawn from this:

    1) Salmon don't like transmitters up their asses
    2) Setnets don't catch Chinooks

    These conclusions are just as valid as the ones presented at the BOF, based upon what was presented.

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    The results of the research speak for themselves. The real concern arises when folks try to make management inferences and decisions based on the research. Bad idea. Especially when you consider that the study involved tracking the behavior of individual fish, who have been captured, handled, tagged, revived, and then released. As Seinerman so inartfully described, this can and does affect fish behavior. It's okay to discuss and debate the implications of the research, but please NOBODY should be basing management decisions on the results.

    There was similar research done in the Columbia River by the same organization. The results were interesting, but they did not lead to any changes in how the fisheries are managed, primarily due to small sample size and tagging bias. In other words, there were too few fish being tagged, and the individual tag burden was too high to extrapolate the results to the run-at-large.

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    Quote Originally Posted by Cohoangler View Post
    As Seinerman so inartfully described, this can and does affect fish behavior. It's okay to discuss and debate the implications of the research, but please NOBODY should be basing management decisions on the results.
    Ouch! I thought I was being colorful. After all, I'm just a boat captain....

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    You were being colorful! But since I'm a fish biologist/scientist (and you're a boat captain), I don't have the luxury of describing science using the terms you did. But we both agree on the limitations of the techniques used in the research, even though we describe them differently. Cheers!

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    Quote Originally Posted by Cohoangler View Post
    You were being colorful! But since I'm a fish biologist/scientist (and you're a boat captain), I don't have the luxury of describing science using the terms you did. But we both agree on the limitations of the techniques used in the research, even though we describe them differently. Cheers!
    Roger that! I also agree that "NOBODY should be basing management decisions on the results." Cheers to you, too!

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    Quote Originally Posted by Seinerman View Post
    Roger that! I also agree that "NOBODY should be basing management decisions on the results." Cheers to you, too!
    I know this is a sore point but nobody should be basing management actions on projects that have little data or no evaluation. Is not the gear type options the same as the outcome from the chinook study? There appears to be an attitude that no study or significant evaluation is needed for changing a whole gear type (set net ban, seines, traps, live boxes) but changing to 29 inch mesh based on a flawed tagging study is wrong. I see this as both the same from a philosophical viewpoint.

    I still keep asking the question - how many chinook salmon have to be moved to the river to make the chinook allocation debate go away. I know Bob Penney's answer - all of them. But what about Yukon, iceblue, and other in-river users? Can someone just give a simple answer. Assume the present ESSN harvest rate is 15% - what does it have to be to make the discussion go away from an allocation viewpoint.

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    For the sake of discussion, I'm curious what, if anything, people think setnetters should do about this. I'm not opposed to 29 mesh nets, but the restrictions passed at the BOF were based pretty heavily on this research, and now ADFG is refuting much of it.

    Also, I'm curious about ADFG's purpose in releasing this report at this time. Did it just take a while to produce? Are they trying to fend off seeing the state waste any additional money on these contractors, or is the only explanation that they are trying to stand up for good science? I consider it a solid either way, just as I did the ADFG genetics guys who completely destroyed the genetics component of this research in their BOF testimony. That was funny!

    Again, just curious and not suggesting anything with either question, other than spirited discussion!

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    Quote Originally Posted by Nerka View Post
    I know this is a sore point but nobody should be basing management actions on projects that have little data or no evaluation. Is not the gear type options the same as the outcome from the chinook study? There appears to be an attitude that no study or significant evaluation is needed for changing a whole gear type (set net ban, seines, traps, live boxes) but changing to 29 inch mesh based on a flawed tagging study is wrong. I see this as both the same from a philosophical viewpoint.

    I still keep asking the question - how many chinook salmon have to be moved to the river to make the chinook allocation debate go away. I know Bob Penney's answer - all of them. But what about Yukon, iceblue, and other in-river users? Can someone just give a simple answer. Assume the present ESSN harvest rate is 15% - what does it have to be to make the discussion go away from an allocation viewpoint.
    My understanding of the commish permit in UCI is to begin gathering data. For example, can a seine actually be set and retrieved? If not, then there is no reason to go any further. Once it is determined that a seine can be set and retrieved, what is the CPU and how does it compare with a gillnet? Is the efficacy enhanced or diminished if there are setnets or other gear in the water? How many Chinook are harvested? How does that percentage compare with setnets? What is the mortality (or in OR, the morality) rate on released salmon?

    There are similar experiments going on in WA and OR on the Columbia River. Over time, the data sufficiency and insufficiencies will present themselves. At this time, there are no proposals to make regulatory changes regarding the experimental permit. There is a huge difference between an experimental fishery and a regulatory proposal. Don't conflate the two. The 29 in mesh was based on this "study" - there are no proposals to allow optional gear based on the experimental seine permit.

    As for the set net ban, looks like that one is up to the courts at this time (we'll see if it even gets to the voters).

    I agree with you on your last paragraph, though. And part of the problem is the fact that one group simply wants to eliminate another. If the ESSN exploitation rate was 2%, that would be too much, even if there were huge Chinook escapements. The argument to eliminate ESSN fisheries was going on back in years when there were banner Chinook returns.

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    Quote Originally Posted by smithtb View Post
    the ADFG genetics guys who completely destroyed the genetics component of this research in their BOF testimony. That was funny!
    Not sure what was so funny.

    Fish that committed to the Kenai did NOT assign to the existing genetic database for Kenai.

    Either there's a hella'lotta straying going on...

    OR...

    the genetic database for Kenai kings is flawed.

    Your pick....
    "Let every angler who loves to fish think what it would mean to him to find the fish were gone." Zane Grey
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    Quote Originally Posted by fishNphysician View Post
    Not sure what was so funny.

    Fish that committed to the Kenai did NOT assign to the existing genetic database for Kenai.

    Either there's a hella'lotta straying going on...

    OR...

    the genetic database for Kenai kings is flawed.

    Your pick....
    Their testimony was amusing. "Ummm, well sir, there's nothing scientific about these results". Or something to that effect.

    Perhaps funny was a somewhat callous choice of words, but given the circumstances, I don't feel too bad looking for humor in unlikely places.

    To your comment, I would expect both.

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    Quote Originally Posted by Seinerman View Post
    My understanding of the commish permit in UCI is to begin gathering data. For example, can a seine actually be set and retrieved? If not, then there is no reason to go any further. Once it is determined that a seine can be set and retrieved, what is the CPU and how does it compare with a gillnet? Is the efficacy enhanced or diminished if there are setnets or other gear in the water? How many Chinook are harvested? How does that percentage compare with setnets? What is the mortality (or in OR, the morality) rate on released salmon?

    There are similar experiments going on in WA and OR on the Columbia River. Over time, the data sufficiency and insufficiencies will present themselves. At this time, there are no proposals to make regulatory changes regarding the experimental permit. There is a huge difference between an experimental fishery and a regulatory proposal. Don't conflate the two. The 29 in mesh was based on this "study" - there are no proposals to allow optional gear based on the experimental seine permit.

    As for the set net ban, looks like that one is up to the courts at this time (we'll see if it even gets to the voters).

    I agree with you on your last paragraph, though. And part of the problem is the fact that one group simply wants to eliminate another. If the ESSN exploitation rate was 2%, that would be too much, even if there were huge Chinook escapements. The argument to eliminate ESSN fisheries was going on back in years when there were banner Chinook returns.
    There are no studies to answer you questions - can a seine be set in UCI - we already know that it can. Been there and done that when we tagged fish down at Anchor Point. The question is at what locations and under what circumstances. A single net fishing one location will not answer that.

    Compare CPUE to seine catches. Impossible to do as that requires some type of modeling and catch efficiency data. Also there is no CPUE data for the gill net fishery.

    How many chinook are harvested - depends on how many times the gear is set. Most gill nets do not catch a chinook salmon in a 12 hour fishing period. The whole catch on a good day is 500-600 chinook in the set net fishery when 1000 nets are fishing.

    No idea on how to compare percentage of chinook to sockeye with either gear under the present single net approach.

    So lets assume the seine cannot be fished at this one location. Does that mean it should not be pursued for other locations?

    Just a bad way to do science with a commissioner permit. Also, the 29 inch mesh did not just come about because of the tagging study. In fact, that had little to do with it. A single set net fisherman did his experiment and convinced a Board member that this was the way to go. No data at all that was worth anything.

    So unless a double standard applies the chinook tagging study and gear studies should be viewed as the same.

  19. #19

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    Quote Originally Posted by Nerka View Post
    There are no studies to answer you questions - can a seine be set in UCI - we already know that it can. Been there and done that when we tagged fish down at Anchor Point. The question is at what locations and under what circumstances. A single net fishing one location will not answer that.

    Compare CPUE to seine catches. Impossible to do as that requires some type of modeling and catch efficiency data. Also there is no CPUE data for the gill net fishery.

    How many chinook are harvested - depends on how many times the gear is set. Most gill nets do not catch a chinook salmon in a 12 hour fishing period. The whole catch on a good day is 500-600 chinook in the set net fishery when 1000 nets are fishing.

    No idea on how to compare percentage of chinook to sockeye with either gear under the present single net approach.

    So lets assume the seine cannot be fished at this one location. Does that mean it should not be pursued for other locations?

    Just a bad way to do science with a commissioner permit. Also, the 29 inch mesh did not just come about because of the tagging study. In fact, that had little to do with it. A single set net fisherman did his experiment and convinced a Board member that this was the way to go. No data at all that was worth anything.

    So unless a double standard applies the chinook tagging study and gear studies should be viewed as the same.
    You say tomato, I say tamahto. There is still a big difference between the first step in answering a larger question, and a regulatory proposal. Also, I was at the meeting, and that Kintana study was referred to quite frequently in support of that one fisherman's proposal. There is probably no perfect way to get the information, but there is a huge difference between the commish permit and a proposed regulation change. That's all I'm saying. I agree that there is a lot of information needed before the viability or efficacy of a beach seine on a set net location is proposed as regulation. Maybe next year 10% of the setnetters use the commish permit and gather more data and two board cycles out there is enough data for a presentation. The Pollock test fishery started out as one boat, then there were two boats. So far, the results have been mixed, but at least there is some information to use to move forward with the experiment. Before the Pollock test fishery, there was no information. Now, to present the limited information to the board as a study - that would be flawed for the same reason the "can up the ass" study was flawed. I just think it is way too premature to lump the two issues together.

    Also, seining is allowed below Anchor Point. The ESSN fishermen most impacted are north of the Kasilof river. Completely different dynamics. I seine around drift gillnets, and I can tell you that this is going to be a formidable undertaking. I personally doubt that there is an anchor or staking system solid enough to even set a seine from the beach during a running tide, much less to consistently repeat a set in a manner that is efficient. I think it would be easier for offshore setnetters to swing a seine around their buoy with a skiff.

    Anyway, it's been fun. You can have the last word. I'm off to go fishing for a living. Hope you find some cool birds this summer, and play nice with these guys.

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    Quote Originally Posted by Seinerman View Post
    You say tomato, I say tamahto. There is still a big difference between the first step in answering a larger question, and a regulatory proposal. Also, I was at the meeting, and that Kintana study was referred to quite frequently in support of that one fisherman's proposal. There is probably no perfect way to get the information, but there is a huge difference between the commish permit and a proposed regulation change. That's all I'm saying. I agree that there is a lot of information needed before the viability or efficacy of a beach seine on a set net location is proposed as regulation. Maybe next year 10% of the setnetters use the commish permit and gather more data and two board cycles out there is enough data for a presentation. The Pollock test fishery started out as one boat, then there were two boats. So far, the results have been mixed, but at least there is some information to use to move forward with the experiment. Before the Pollock test fishery, there was no information. Now, to present the limited information to the board as a study - that would be flawed for the same reason the "can up the ass" study was flawed. I just think it is way too premature to lump the two issues together.

    Also, seining is allowed below Anchor Point. The ESSN fishermen most impacted are north of the Kasilof river. Completely different dynamics. I seine around drift gillnets, and I can tell you that this is going to be a formidable undertaking. I personally doubt that there is an anchor or staking system solid enough to even set a seine from the beach during a running tide, much less to consistently repeat a set in a manner that is efficient. I think it would be easier for offshore setnetters to swing a seine around their buoy with a skiff.

    Anyway, it's been fun. You can have the last word. I'm off to go fishing for a living. Hope you find some cool birds this summer, and play nice with these guys.

    I will try. It is nice to have a conversation without any personal attacks - if anyone knows how to seine it is you so good luck out there.

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