Fraser River sockeye salmon: data synthesis and cumulative impacts

Model: A4bBrood years: 1969-2001A second set of analyses were performed on a modified version of this model set, in which dataon the abundance of pink salmon in the Northeast Pacific and from Russia were added. Theanalysis was extended to include pink salmon because: 1) the hypothesis that competition withodd-year pink salmon is a factor that has potentially contributing to the decline of Fraser Riversockeye salmon productivity was included in the Expert Panel’s Report to the Pacific SalmonCommission (Peterman et al., 2010), though not included among the Cohen commissionTechnical Reports; and 2) the data were made readily available to us from an early date. Asidentified in Appendix 4-3 Data preparation pink salmon are hypothesized to compete withsockeye during their forth year (i.e., second ocean year). For the purpose of this analysis theywere lined up with life stage 4b, Return to the Fraser and included in Model 6. The results forthis analysis were similar to the previous analysis with M10 achieving the lowest AICc, but nowM4 (Inshore Migration) receives strong support as well.Table A4.3-6. A4b candidate models ordered by AICc from best (lowest) to worst (biggest). M.ID=modelidentification, M.AIC=the estimated AIC for the model, num.obs=the total number of observations (i.e.,complete rows in the data set), num.par=the total number of fixed effects + random effects, Correction= thedifference between the AICc (corrected for small sample size compared to number of parameters) and theAIC, M.AICC= the AICc for the model, min.AICC = the smallest AICc observed within the model set,delta= the difference between the min.AICC and each M.AICC, and AICC_wts= the Akaike weight (i.e.,support) for each model.M.ID M.AIC num.obs num.par Correction M.AICC min.AICC delta AICC_wtsM10 1130.72 463 43 9.03 1139.75 1139.75 0 58.75M4 1135.78 463 32 4.91 1140.69 1139.75 0.94 36.66M6 1142.88 463 28 3.74 1146.62 1139.75 6.87 1.89M1 1133.22 463 52 13.44 1146.66 1139.75 6.91 1.85M5 1146.65 463 21 2.10 1148.75 1139.75 9.00 0.65M8 1151.31 463 19 1.72 1153.02 1139.75 13.27 0.08M2 1151.31 463 19 1.72 1153.02 1139.75 13.27 0.08M7 1152.93 463 23 2.51 1155.44 1139.75 15.69 0.02M3 1155.74 463 25 2.97 1158.71 1139.75 18.96 0.0045M9 1156.46 463 26 3.22 1159.68 1139.75 19.93 0.0028241