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  • #16
    Originally posted by Cohoangler View Post
    However, on the Kenai River, it would not surprise me if the ER has a stream-type life history while the LR has an ocean-type life history.
    The overwhelming majority of Kenai kings smolt as yearlings (destined for 1.1, 1.2, 1.3, 1.4, and 1.5 phenotypes)... in BOTH the trib and the mainstem stocks. Very few ocean-type subyearling smolts (0.*) , and even fewer spend a second winter in the river (2.*)
    "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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    • #17
      Originally posted by Nerka View Post
      They may be correct that lower goals will produce better spawner/return ratios. Time will tell.
      While ratios are good, sheer numbers are also good. This is the subject of hot debate. Is it better to strive for a 100 fish return that produces 10:1, or a 500 fish return that produces 2:1? My contention is that as you lower the goal, striving to make the best ratios, you open yourself up more to collapse. The fewer fish coming back, the less room for variables such as fishing success, predation, stream and ocean conditions, etc. The more salmon that return, the more available for all user groups and the environmental needs. A big kicker to increased run sizes is when we have extreme heat and drought conditions as we did this year, when water temperatures, flow, and oxygen levels only support a very small number of adult fish, and anything over that number will just die off, overcrowd the stream, and make the oxygen situation worse.

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      • #18
        I'll take MSA over MSY any day... Maximum Sustained Abundance.
        "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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        • #19
          Originally posted by fishNphysician View Post
          I'll take MSA over MSY any day... Maximum Sustained Abundance.
          Amen. I wish there were a way to adjust goals a bit according to conditions. When water is very hot and low, the maximum sustained abundance is lower than when conditions are normal. Yet current goal management doesn't make allowances for extreme weather events. After a year or two of very low recruitment, if conditions are ideal, the rivers could benefit from "over" escapement the next year.

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          • #20
            Originally posted by fishNphysician View Post
            I'll take MSA over MSY any day... Maximum Sustained Abundance.
            Please define where on the production curves this is located? Are you talking about Maximum Abundance? If so if runs decrease Max Abundance will also decrease. Not sure how you define what you are promoting. Are you using something other than a production curve?

            Also one has to forget about spawner/return ratios. By definition they go up at lower spawning levels - left side of the Ricker Curve. What I think people are saying and you may be correct. When production turns down and no one knows why the curves will reflect lower returns for the same number of spawners. In the Kenai if you just take the last decade in the data set the MSY value used by ADFG today is beyond the replace point. They point this out in their report. They did not lower the goals for Kenai. It may cost the industry lots of money and that may be OK if that is what the public wants. However, ADFG has not done the habitat work or freshwater work to help one decide the best course of action.

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            • #21
              Originally posted by Nerka View Post
              Please define where on the production curves this is located? Are you talking about Maximum Abundance? If so if runs decrease Max Abundance will also decrease. Not sure how you define what you are promoting. Are you using something other than a production curve?.
              To keep it in terms of the entrenched paradigm, Ricker curve at R-max.... top of the roller coaster.... to the right of R-msy and to the left of equilibrium.
              "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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              • #22
                As I recall, the peak of the curve represents the number of adults needed to maximize the number of recruits. On either side of that point, the number of recruits decreases, perhaps precipitously depending on the shape of the curve. That would be max abundance.

                It might not be max sustained abundance, but I'm not sure anything about a Ricker curve can be considered 'sustained". It's been shown that MSY can produce maximum yield but it is certainly not sustainable (largely due to external factors that limit productivity).

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                • #23
                  Any stock purportedly managed for a rec priority needs be managed for MSA.
                  "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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                  • #24
                    Originally posted by fishNphysician View Post
                    Any stock purportedly managed for a rec priority needs be managed for MSA.
                    OK, Please tell us what the MSA is for the Deshka. The truth is, you can't. Because there is no such critter. It changes from year to year due to the variety of external factors that Cohoangler mentioned. But go ahead, take a stab at it and tell us what you think that number is. And while you are at it, maybe explain why, if it works, it shouldn't be used for fisheries that are purportedly managed for commercial priority also or even a variety of priorities? It sounds like a panacea for all that ails salmon stocks.
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                    • #25
                      Originally posted by twodux View Post
                      OK, Please tell us what the MSA is for the Deshka. The truth is, you can't. Because there is no such critter. It changes from year to year due to the variety of external factors that Cohoangler mentioned. But go ahead, take a stab at it and tell us what you think that number is. And while you are at it, maybe explain why, if it works, it shouldn't be used for fisheries that are purportedly managed for commercial priority also or even a variety of priorities? It sounds like a panacea for all that ails salmon stocks.
                      See post #21.... for a harvested population, the MSA escapement occurs at the apex of the Ricker curve.

                      The historic bias of fishery managers clinging to the MSY-mantra is because that is theoretically where the difference between escapement and recruitment is greatest.... allowing that difference to be "sustainably" removed from the pool of adult recruits. This is the essence of the "yield" concept.... the amount that can theoretically be removed (exploited/harvested) from the adult return... and managing to maximize that yield.

                      MSA occurs at a higher spawner escapement where recruitment is greatest. This works better for a rec fishery dependent on opportunity. For an angler, opportunity starts with a bite. And since we know they all ain't biters, maximizing opportunity is predicated on maximizing abundance. In a rec fishery, more fish means more bites which means more opportunity. The theoretic "yield" in that scenario is admittedly less than at the MSY escapement.... but for someone fishing for recreation, the importance of dead fish in the box is not as great as in a commercial fishery where it is 100% all about the dead fish in the box.
                      "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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                      • #26
                        This is a good thread to stimulate conversation-
                        You use the term MSA but I believe the correct term is MSR or more recently MSP.
                        The term MSR has traditionally been called “maximum recruitment” (Rm; Ricker 1975, pgs 283-285), more recently “maximum sustained production” (Fleischman et al. 2012). One way to define it is the maximum point of the stock-recruit model where average recruitment over time is at the peak.

                        The state policy for escapement goal states- "maximum sustained yield" or "(MSY)" means the greatest average annual yield from a salmon stock; in practice, MSY is achieved when a level of escapement is maintained within a specific range on an annual basis, regardless of annual run strength; the achievement of MSY requires a high degree of management precision and scientific information regarding the relationship between salmon escapement and subsequent return; the concept of MSY should be interpreted in a broad ecosystem context to take into account species interactions, environmental changes, an array of ecosystem goods and services, and scientific uncertainty;"

                        One of the key elements to MSY is maintaining harvest regardless of run strength to stay within the range.
                        So should a sport fishery on Lake Creek or other streams with the only enumeration is after the season aerial index counts have a goal that requires the the precision that MSY states be the appropriate goal, in other words should be have a goal that we can't manage for? On a river like the Deshka we do have some real time counting( weir) but does the sport fishery have the harvest power to stay within the goal on large returns?

                        I would love to hear thoughts on this.

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                        • #27
                          Originally posted by fishNphysician View Post
                          See post #21.... for a harvested population, the MSA escapement occurs at the apex of the Ricker curve.

                          The historic bias of fishery managers clinging to the MSY-mantra is because that is theoretically where the difference between escapement and recruitment is greatest.... allowing that difference to be "sustainably" removed from the pool of adult recruits. This is the essence of the "yield" concept.... the amount that can theoretically be removed (exploited/harvested) from the adult return... and managing to maximize that yield.

                          MSA occurs at a higher spawner escapement where recruitment is greatest. This works better for a rec fishery dependent on opportunity. For an angler, opportunity starts with a bite. And since we know they all ain't biters, maximizing opportunity is predicated on maximizing abundance. In a rec fishery, more fish means more bites which means more opportunity. The theoretic "yield" in that scenario is admittedly less than at the MSY escapement.... but for someone fishing for recreation, the importance of dead fish in the box is not as great as in a commercial fishery where it is 100% all about the dead fish in the box.
                          It only works for recreational fisheries that do not want to have a yield priority. It is dangerous to take this route because the number of spawners is greater and the ability to reach that number is a probability. Sometimes one should beware of what they ask for. Also saying MSY does not work or is not achievable is not true. It works as a policy to put escapement first relative to harvester demands. It works because people should understand it is based on average returns not what happens in a given year. It has worked in Alaska because users and founders of the State at the time of statehood understood policy, expectations, and actions needed to come back from federal overharvest.

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                          • #28
                            Originally posted by SkwentnaMan View Post
                            This is a good thread to stimulate conversation-
                            You use the term MSA but I believe the correct term is MSR or more recently MSP.
                            The term MSR has traditionally been called “maximum recruitment” (Rm; Ricker 1975, pgs 283-285), more recently “maximum sustained production” (Fleischman et al. 2012). One way to define it is the maximum point of the stock-recruit model where average recruitment over time is at the peak.

                            The state policy for escapement goal states- "maximum sustained yield" or "(MSY)" means the greatest average annual yield from a salmon stock; in practice, MSY is achieved when a level of escapement is maintained within a specific range on an annual basis, regardless of annual run strength; the achievement of MSY requires a high degree of management precision and scientific information regarding the relationship between salmon escapement and subsequent return; the concept of MSY should be interpreted in a broad ecosystem context to take into account species interactions, environmental changes, an array of ecosystem goods and services, and scientific uncertainty;"

                            One of the key elements to MSY is maintaining harvest regardless of run strength to stay within the range.
                            So should a sport fishery on Lake Creek or other streams with the only enumeration is after the season aerial index counts have a goal that requires the the precision that MSY states be the appropriate goal, in other words should be have a goal that we can't manage for? On a river like the Deshka we do have some real time counting( weir) but does the sport fishery have the harvest power to stay within the goal on large returns?

                            I would love to hear thoughts on this.
                            Correct... I am using MSA (maximum sustained abundance) and MSR (maximum sustained recruitment) synonymously. The Holy Grail objective in the MSA/MSR paradigm is to consistently produce the greatest abundance of adult recruits in perpetuity. This is the management objective that that works best in a rec fishery dependent on sustainable abundance to optimize opportunity.

                            By definition, it is sustainable and still produces a generous harvestable yield... only with fewer fish available for exploitation and allowing a greater spawning escapement than when we manage for an MSY objective.

                            Inability to enumerate escapement in-season doesn't necessarily preclude an MSY goal... it just makes it hella'tougher to achieve without a more precautionary approach.

                            The other problem with an MSY range for escapement is that it automatically skews the management toward the lower bound of the MSY goal. That's just the unavoidable reality of human nature. At least that's what history show us.
                            "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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                            The KeenEye MD

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                            • #29
                              d
                              Originally posted by Nerka View Post
                              It works because people should understand it is based on average returns not what happens in a given year. It has worked in Alaska because users and founders of the State at the time of statehood understood policy, expectations, and actions needed to come back from federal overharvest.
                              Nerka, I respectfully disagree. Saying management of our fisheries works, and has worked as it is, ignores the fact of the Susitna River chinook returns. If the model and its practice worked, chinook returns to the Susitna would still sustain sport fishing. The Parks Highway streams, which each sustained 10's of thousands of angler hours for 2 decades, are decimated to the point there is zero retention allowed, for many years now. Last year saw no fishing of any kind targeting kings on the Parks Hwy streams. That closure extended into all other Susitna Rivers and also the Yentna. Management has been far too slow to recognize change and adjust the way things are done, and this is the result of the management "that works." As to Federal regulations and fisheries wrecking our state fisheries, and Alaska solving that problem after statehood, I present to you the Federally run pollock fishery. Halibut quotas. And the marine mammal protection act. Its way past time to quit saying "our management is great, and works well, is the best managed fishery in the nation, etc," and look at why it no longer works, and what changes need to be made.

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                              • #30
                                Originally posted by willphish4food View Post
                                dNerka, I respectfully disagree. Saying management of our fisheries works, and has worked as it is, ignores the fact of the Susitna River chinook returns. If the model and its practice worked, chinook returns to the Susitna would still sustain sport fishing. The Parks Highway streams, which each sustained 10's of thousands of angler hours for 2 decades, are decimated to the point there is zero retention allowed, for many years now. Last year saw no fishing of any kind targeting kings on the Parks Hwy streams. That closure extended into all other Susitna Rivers and also the Yentna. Management has been far too slow to recognize change and adjust the way things are done, and this is the result of the management "that works." As to Federal regulations and fisheries wrecking our state fisheries, and Alaska solving that problem after statehood, I present to you the Federally run pollock fishery. Halibut quotas. And the marine mammal protection act. Its way past time to quit saying "our management is great, and works well, is the best managed fishery in the nation, etc," and look at why it no longer works, and what changes need to be made.
                                Will you are just so wrong and failed your history test. The federal fisheries you referenced are a direct result of the MSA which I think was passed in 1976. The White Act governed salmon management in the 1950's in Alaska. That required 50% harvest of all returns. Unfortunately there was no assessment and the Federal Gov overharvested UCI fish. The State management brought back the Susitna chinook salmon. You cannot blame the lower chinook returns if the lower returns are due to a change in overall productivity. Sorry but your just wrong. Management has closed fisheries to meet goals. If those goals are wrong so be it. But you cannot blame the State. Are you saying they overharvested those streams.

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