Model results for salmon survival.

Comparison of models describing variation in survival of Snake River sp/su Chinook salmon based on conditions during juvenile emigration (1998 to 2008). PDO7_9 =  mean value from July to September; CCI6 =  Copepod Community Index in June; CPUE6 =  catch of yearling Chinook (fish km−1) in June; NPGO4_6 =  mean value from April to June; and CRFlow4_7 =  Columbia River flow from April to July. RSS  =  residual sum of squares, AICc  =  Akaike Information Criteria adjusted for small sample size. represents the difference between the AICc of the best model and the others. indicates the relative likelihood of the model given the data. Variables were transformed (logarithm or square root) to normalize distributions and homogenize variances.

基于1998年至2008年幼体洄游阶段的环境条件，对描述斯内克河春/夏型奇努克鲑鱼（Snake River spring/summer Chinook salmon）存活率变异的各类模型进行比较。其中：PDO7_9为7-9月平均值；CCI6为6月桡足类群落指数（Copepod Community Index）；CPUE6为6月一龄奇努克鲑鱼捕捞量（尾·千米⁻¹）；NPGO4_6为4-6月平均值；CRFlow4_7为哥伦比亚河4-7月径流量。RSS为残差平方和（residual sum of squares），AICc为小样本校正赤池信息准则（Akaike Information Criteria adjusted for small sample size）。某符号指代最优模型与其余模型的AICc值之差，另一符号指代给定数据集下各模型的相对似然值。所有变量均经过对数变换或平方根变换，以实现分布正态化与方差齐性。