Fraser River Sockeye Fisheries and Fisheries Management - Cohen ...

(budgets, legal issues, pseudo-conservation goals, etc.). A substitute recommendation would beto reverse this trend, and improve test fishing operations. These two adjustments might havehelped better manage the unusually large returns of 2010 as well.LGL Response: The reviewer comments refer to both pre-season forecasts and in-seasontest fishing practices. We obviously disagree with the reviewer’s point of view that preseasonforecasts are important for the management of Fraser sockeye fisheries. As statedin our report, “the recognized challenges with forecasting salmon returns have led mostmanagers to rely on in-season information to manage sockeye fisheries.” We definitelysupport the continued use and improvement of in-season assessments and forecastingefforts. However, the in-season systems are reasonably good and the biggest deficiency inmanagement of Fraser sockeye fisheries is the lack of clearly defined escapement goals.Therefore, we stand firmly behind recommendation #3.Recommendation #7 states that en-route losses should be estimated (fair enough), and theestimates should be ‘incorporated’ into run-reconstruction procedures. These deterministicaccounting procedures are dated, and more sophisticated models should be used for allassessments in BC. As for recommendation #8, as noted earlier, it is superfluous.LGL Response: With regard to Recommendation #7, run-reconstruction procedures havebeen used for many years to assess returns for Pacific salmon stocks. While moresophisticated models could be developed, the three important reasons why runreconstructionmethods continue to be used: (1) these methods integrate all the availableinformation on run-timing, migration speeds, en-route losses, stock composition, catch andescapement to produce run size and exploitation rate estimates for each stock, (2) thesemethods and results can be readily understood by fisheries managers and the variousfishing sectors that are being managed, and (3) they emphasize the importance of reliableestimates of catch and escapement that are essential for management of salmon fisheries.The reviewer’s comments regarding Recommendation #8 have been addressed above.Some attention should focus on the reliability of the ageing methods and sampling rates used byDFO + ADF&G in providing accurate estimates of the age composition in catches and adultreturns. Age composition estimates based on scale patterns can be subject to considerableuncertainty due to sampling deficiencies and reader subjectivity. It could be hypothesized thatpoor ocean conditions may simply have lead some sockeye to remain at sea one year longer. Theextent of phenotypic plasticity for Fraser River sockeye stocks is not well known, but if true, thishypothesis could help explain why there was an abnormally low return in 2009, followed by anabnormally high return in 2010. Basically some sockeye expected to return in 2009 would haveM-24