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Kenai ER king escapement objectives... time for a change?

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  • #16
    Doc, the early run goal is based on maximum production, not maximum yield. The quality of the data used in the calculation remains an open question, fancy models and graphs not withstanding.

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    • #17
      Originally posted by Bfish View Post
      Doc, the early run goal is based on maximum production, not maximum yield. The quality of the data used in the calculation remains an open question, fancy models and graphs not withstanding.
      thanks bf. Doc is way off on this one. The main issues with chinook is counting and management approach in river.

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      • #18
        Originally posted by Nerka View Post
        The main issues with chinook is counting and management approach in river.
        Agreed.

        Since we don't have complete confidence in our ability to enumerate the fish, shooting for a bigger goal is simply more precautionary and conservative.

        Moreover, a bigger goal enhances diversity and fecundity. The big fish are gone, particularly the big hens. How do we ever expect to get them back? When the run is so depleted and skewed toward males, how on earth are we gonna get any meaningful production out of the gravel when its swamped by 80% jacks? At the very least, a bigger goal increases the chance of putting more hens on the gravel. A bigger goal increases the chance of a BIG hen finding her way to the gravel.

        You guys can say what you want, but it's MSY that has driven modern-day fish management.... it's the cornerstone of doing a Ricker analysis (or other spawner-recruit model) in the first place. The emphasis is and has always been focused on finding the minimum escapement that allows the maximum use of the resource. Anyone who denies that basic tenet is not being intellectually honest. I for one believe that mindset is a POOR fit for the long term conservation of an exploited species. I would say historic performance of "managed" fisheries thru the ages supports my belief. This notion that we can have "more for less" can be (and most assuredly has been) taken to extremes.

        As I alluded to earlier.... less begets less... pure and simple. I've seen it everywhere I've been involved with fish management. As stocks decline a new Ricker curve is simply drawn up based on the lower numbers of returning fish. And lo and behold, the new MSY spawner goal is lower as well.

        Imagine that? Who'da'thunk'it?

        Without exception, these depleted runs are simply assigned a new and improved e-goal... and guess what.... it's always smaller than the previous. In essence what's being conserved in these "managed" populations is not the fish but instead the ability to keep fishing on them. Under the MSY mantra, no matter how small the population shrinks over time, there's always a theoretic portion of the population that is "sustainably" expendable for exploitation. After watching it applied in action over my lifetime, I see NOTHING either maximal or sustainable with the MSY model.... but rather only perpetual depletion.
        "Let every angler who loves to fish think what it would mean to him to find the fish were gone." Zane Grey
        sigpic
        The KeenEye MD

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        • #19
          Originally posted by Bfish View Post
          Doc, the early run goal is based on maximum production
          Gee, how's that working out?
          "Let every angler who loves to fish think what it would mean to him to find the fish were gone." Zane Grey
          sigpic
          The KeenEye MD

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          • #20
            I noticed something in looking over the literature Doc was kind enough to link. In the ER, bait is only open after the top end of the goal is projected to be achieved. For the ER, bait is a liberalization, not the norm.

            In the LR, bait is listed as a restriction anytime the midpoint of the goal is not expected to be achieved. If bait is not allowed to be used inriver, other fisheries face restrictions in order to share the burden of conservation. For the LR, bait is the norm.

            Interesting.

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            • #21
              Doc no matter how you cut it MSY as a concept works for stocks that are counted well and the fishing power is there to harvest fish. If these do not exist then any goal is going to be difficult to achieve. Your point is that goals are lowered on poor returns to allow fishing. That would be a wrong approach if the data are sound and habitat is still good. ADFG changed goals to correct for over counting due to sockeye not lowered production. Therefore the high numbers you referenced in the past were bogus.

              It could be that the early part of the main stem spawners were overharvested and thus the tributaries production was masked by mainstem spawning fish. It is time to start thinking in these terms and see how the fishery should be designed. Changing to a higher goal without counting better or understanding production issues is having cart before the horse. ADFG is pretty conservative in management in June. They need to rethink july.

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              • #22
                Originally posted by Nerka View Post
                Doc no matter how you cut it MSY as a concept works for stocks that are counted well and the fishing power is there to harvest fish.
                And if there is little variability around the annual pre-season forecast, and there is little variation in our ability to estimate stock size, and there is little influence from environmental variables such as ocean conditions, and there is little change in the productivity of either the freshwater or saltwater habitat, or there is little change in the fishers ability to harvest, and we have complete confidence in the data to make the necessary calculations. In other words MSY works great on paper. In reality, the vagaries of the real world render it less successful than we care to admit. But as someone famous once said: "Let's not let reality get in the way of a good model."

                And, MSY doesn't account for the importance of marine-derived nutrients in the long-term health of the watershed or the fish stocks therein. But don't get me started that on point. We've been down that road too many times......

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                • #23
                  This thread (along with untold numbers of other thread over the YEARS) is/are perfect examples of what is wrong with our system. Debating, discussing, comparing, analyzing, and then dismissing reality. The eggheads with Phd's and their 'science' are seemingly more intent to prove THEY are right, and '****' the resource of which they speak.
                  Now, DECADES later, here we are. The problem clearly evident. All the expert pundits still opining. The same lobbyists lobbying. The same band aid methodology being applied year after year.
                  Sad,sad, sad! If ANY common sense EVER was applied to this situation, the bloviations would cease. The managers would finally step up and do the right thing for this resource. They would close the INriver fishery for king salmon for a few years and rebuild the stocks.
                  The setnets have been fishing throughout the Big King heydays. The INriver big King fishery thrived. It was decimated by the INriver fishing TARGETTING BIG KINGS FOR DECADES. It's that simple.
                  Will common sense ever prevail? Sadly, probably not. Too bad we didn't take this simple action 15-20 years ago. We wouldn't be having these discussions.
                  Your sarcasm is way, waaaayyyyyyyy more sarcastic than mine! :whistle:
                  WWG1WGA! QANON

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                  • #24
                    Originally posted by Nerka View Post
                    Doc no matter how you cut it MSY as a concept works for stocks that are counted well and the fishing power is there to harvest fish. If these do not exist then any goal is going to be difficult to achieve. Your point is that goals are lowered on poor returns to allow fishing. That would be a wrong approach if the data are sound and habitat is still good. ADFG changed goals to correct for over counting due to sockeye not lowered production. Therefore the high numbers you referenced in the past were bogus.

                    It could be that the early part of the main stem spawners were overharvested and thus the tributaries production was masked by mainstem spawning fish. It is time to start thinking in these terms and see how the fishery should be designed. Changing to a higher goal without counting better or understanding production issues is having cart before the horse. ADFG is pretty conservative in management in June. They need to rethink july.

                    I'm not sure if the bolded portion of the statement above is referencing goals that were changed prior to 2014, but in 2013 escapement goal recommendation report it discussed Chinook salmon that were passing behind the RM-9 sonar transducer resulting in underestimating Chinook salmon passage. Discussion of this as well as uncertainty in the data can be found in this report:
                    http://www.adfg.alaska.gov/FedAidPDFs/FMS13-03.pdf

                    Here is an excerpt for those who might not have the time to read the entire report:

                    Based on the foregoing analysis, the Alaska Department of Fish and Game recommends a sustainable escapement goal (SEG; definition in 5 ACC 39.222 [f][36]) of 3,800–8,500 Kenai River early-run Chinook salmon.
                    The recommended goal brackets both SMSY and SMAXR. At the lower bound of the recommended range there is a very high (>94%) probability of achieving near-optimal yields (70%, 80%, or 90% of MSY). At the upper end of the range, the probability of optimal yields is much reduced (34%, 17%, and 6% probability of achieving 70, 80, 90% of MSY, respectively), however there is high (99%, 95%, and 77%) probability of achieving near-optimal recruitment (70%, 80%, or 90% of MAXR, respectively). At the center of the range (6,150), there is an 86% probability of achieving 80% of optimal yield and recruitment.
                    The recommended goal is based on actual numbers of spawning fish, so it must be evaluated by accounting for undetected Chinook salmon passing the RM-9 sonar site. This is accomplished by multiplying DIDSON-based estimates of midriver passage by a correction factor to expand the estimates to reflect Chinook salmon passage in the entire cross-section of the river. We recommend a correction factor of 1.55, which is obtained from the state-space model as the inverse of pMR (point estimate 0.65), the fraction of Chinook salmon detected by sonar at RM 9. Projections of harvest and release mortality[1] above RM 9 must be subtracted from expanded DIDSON inriver passage estimates to project escapement during the fishing season.
                    The recommended interim escapement goal has the following attributes:
                    The new goal represents a significant change from the status quo. Because the stock assessment for Kenai River Chinook salmon has changed from split-beam sonar to DIDSON, the old and new goals are based on different currencies and are not comparable. Even though the numerical value of the recommended goal is similar to the existing SEG, the net effect of the new goal may be a substantial change in potential management actions. This effect is difficult to quantify, but can be seen by comparing recent model-derived estimates of annual escapement with the recommended goal (Figure 13). During the most recent four years (2009–2012), when the use of bait was only rarely permitted and restrictions were frequent, annual escapements were 1,400–4,600 fish above the recommended goal. Hypothetically, had this goal been in place during those years, the number and severity of fishery restrictions probably would have been reduced.
                    The new goal is higher than yield considerations alone would dictate. Assuming perfect knowledge of the spawner–recruit relationship (a = 6.3, b = 0.00016) an escapement goal range of 2,871 to 6,464 spawners would provide expected yields of at least 90% of MSY. According to Eggers (1993), an escapement goal range of 3,547 (0.8 × S^MSY point estimate) to 7,094 (1.6 × S^MSY) would provide robust yield performance. Accounting for uncertainty in our knowledge of a, b, and SMSY , a goal of 2,800–6,000 spawners would provide greater than 90% probability of achieving 80% of MSY.[2] The escapement goal review team recommended a goal that was higher than the aforementioned ranges in order to be precautionary and provide an extra margin of safety for the stock in the face of remaining uncertainties (page 18). These uncertainties include sparse pre-2002 data in the early-run reconstruction (one indirect long-term abundance index, two imprecise annual estimates of inriver run), the possible unwanted influence of early-arriving mainstem spawners on the current analysis, and the possible influence of the harvest of tributary spawners in July on this analysis. The large correction for undetected fish required at the RM-9 sonar site also contributes uncertainty to the results. Better information about this quantity will probably be available shortly, after the 2013 season.
                    The new goal will protect the Kenai River early-run Chinook salmon stock from overfishing. Because DIDSON–based assessment represents a large advancement over previous methods, the ability to detect a small run and manage appropriately has been greatly improved. After transition of sonar assessment operations upriver to a site with fewer detection issues, assessment will be further enhanced. By combining accurate assessment with an escapement goal based on comprehensive, up-to-date knowledge of stock dynamics, we will continue to prevent overfishing of the stock.
                    The new goal will benefit fisheries that harvest Kenai River early run Chinook salmon. The new goal will reduce the potential for unnecessary fishery restrictions. Better assessment capabilities facilitate the timely transfer of accurate information to fishery managers during the season. The recommended goal brackets the escapements that provide near-optimal yield and recruitment (Figure 12).
                    It is important to note that goal setting involves trade-offs. As explained above, elevating the goal slightly provides a safety factor in favor of higher escapements, however it may also reduce harvest opportunity during future periods of low abundance. Expected yield (Figure 9) and probability of optimal yield (Figure 8) may also be reduced. Because recruitment (and run size) is maximized at larger numbers of spawning fish than is yield, these sacrifices are partially offset by increased recruitment (Figure 10), and higher probability of optimal recruitment (Figure 12). However any further increase in the goal beyond what is recommended would result in additional sacrifices of yield and recruitment (Figure 12).
                    Small runs are expected for the near future. Results of the run reconstruction and spawner–recruit analysis suggest that the Kenai River early-run stock has been undergoing a decline in productivity. The 2012 total run (5,387 was the smallest on record (Figure 14), representing more than a four-fold decline from peak abundance in 2004 (23,460 fish; Table 8). Similar declines have been documented for other Chinook salmon stocks statewide (ADF&G Chinook Salmon Research Team 2013). Thus far, there is little evidence that the decline will soon be reversed. Based on the current analysis of historical data, escapements of 3,800–8,500 Kenai River early-run Chinook salmon can provide yields averaging approximately 9,000 fish
                    (Figure 9; 80% CI = 2,000–18,000). However this expectation of yield performance is based on “average” stock dynamics across brood years 1986 to 2008. During the five most recent brood years (2004–2008), productivity residuals have been negative (Figure 5d), averaging −0.30 (natural logarithm) units, which is equivalent to a 26% decline in productivity ( ). Figure 9 also shows revised yield expectations, should the reduced productivity of recent brood years continue into the future. Under this scenario, expected yield would be approximately 5,000 for escapements in the goal range, a more than 40% reduction in yield from average conditions.[3]


                    [1] Release mortality is obtained by multiplying creel survey estimates of number of fish released by 0.064 (Bendock and Alexandersdottir 1992).

                    [2] There is no accepted algorithm for selecting an escapement goal with an OYP. The stated range of 2,800–6,000 is one example of a goal based on yield probabilities.

                    [3] Under a modified version of the state-space model developed for forecasting, yield expectations are reduced even further. The modified “TAM” model accommodates a trend in age at maturity. Yield projections from the TAM model are not shown in this report.

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                    • #25
                      It's more than just lifeless numbers on a spreadsheet....

                      AKtally, I've read the report and the rationale behind how you guys arrived at the new SEG. I get how the math works on paper, but again, how about real life?

                      To me it's more than just numbers on a spreadsheet. Escapement by itself is just one metric. What about the quality of that escapement?

                      Tell me this, the models and trade-offs have spit out this new and improved SEG of 3800-8500 for ADFG, but do the models account for variations in age-sex composition? Will 3800-8500 still deliver the goods when the run is 80% jacks and the flagship 4-ocean hens that once carried most of the production burden are now rare as hen's teeth? How does the math account for that?
                      "Let every angler who loves to fish think what it would mean to him to find the fish were gone." Zane Grey
                      sigpic
                      The KeenEye MD

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                      • #26
                        To take it just a bit further, can you expound a bit with specifics about what the agency's thoughts are on a proposed "large fish" goal?
                        "Let every angler who loves to fish think what it would mean to him to find the fish were gone." Zane Grey
                        sigpic
                        The KeenEye MD

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                        • #27
                          Doc's right... it's more than just numbers. My biggest fear is that we'll soon get counts in the mid range of the goal and the Dept. will cave to pressure and open the ER despite the low female and 1.4 counts. When we are talking ER numbers alone don't mean jack. Oops there goes that "Jack" thing again.

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                          • #28
                            Originally posted by Nerka View Post
                            Doc no matter how you cut it MSY as a concept works for stocks that are counted well and the fishing power is there to harvest fish.
                            But, reading between the lines a little bit, I think another of FnP's points is that targeting MSY-levels of spawning escapement isn't necessarily the best route for the in-river fishery. That's a valid point. Higher abundances and escapements, while still quite "sustainable" make for more successful harvesting opportunities. I'd say it applies to subsistence fisheries, too. In fact one aspect in a C&T determination is efficiency of harvest.


                            Additionally, Jeff Bromaghin's work that modeled the effects of Yukon river harvest strategies relating to mesh size/size selectivity is that higher spawning escapements (once the selectivity is reduced/eliminated) can help a stock recover it's diminished traits (fish size) more quickly than it would with lower escapements.
                            http://www.fws.gov/alaska/fisheries/...t_2008_100.pdf
                            "Fishing relaxes me. It's like yoga, except I still get to kill something." --Ron Swanson

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                            • #29
                              Cohoangler. MSY as a concept has been very successful in Alaska. It had users pulling together to maintain msy even though everyone knows the issues of meeting goals and the issues you mentioned. In contrast without the msy concept goals would be lowered and users would drive the political management decisions. Instead I have sat in meeting where fisherman supported closures to reach msy goals. Also they support raising goals for kenai sockeye from 150,000 to 900,000 to 1.2 million in the kenai. That has resulted in average kenai returns of 3 million fish as opposed to 0.5 million. So when someone days msy does not work as a blanket statement I call that just plain simplistic thinking. Each system needs evaluation and discussion of objectives. Doc and you mention quality of escapement and ecosystem impacts and that is fair but do not throw the baby out with the bathwater.

                              One last point is that it is somewhat arrogant to dismiss the role of jacks in population trends. This may be what the population does under stress. We should figure that out or at least consider this point in discussions.

                              Cod stop with the anti phd comments. Makes you look silly. Alaska fishery management has a long history of good practices and good results. Without science users would have over harvest more stocks. Yes Kenai chinook have management issues borne from bad decisions but forums and scientific forums allow identification of all issues. ADFG leadership has failed in Kenai but we have not had a resource trained comissioner for three decades with one exception. Their common sense sucked gas when presented data that required action instead of protecting the image of the office.

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                              • #30
                                Originally posted by Nerka View Post
                                Doc no matter how you cut it MSY as a concept works for stocks that are counted well and the fishing power is there to harvest fish. If these do not exist then any goal is going to be difficult to achieve. Your point is that goals are lowered on poor returns to allow fishing. That would be a wrong approach if the data are sound and habitat is still good. ADFG changed goals to correct for over counting due to sockeye not lowered production. Therefore the high numbers you referenced in the past were bogus.

                                It could be that the early part of the main stem spawners were overharvested and thus the tributaries production was masked by mainstem spawning fish. It is time to start thinking in these terms and see how the fishery should be designed. Changing to a higher goal without counting better or understanding production issues is having cart before the horse. ADFG is pretty conservative in management in June. They need to rethink july.
                                But....the common theme from "on the water folks" is that fishing was better in the past. So wouldn't that reflect that the higher goals were indeed better?

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