grouping. There have been numerous
examples of the coincidence of changes in salmon
productivity with decadal-scale changes in climate and
ocean conditions (Beamish & Bouillon 1993; Hare &
Francis 1995; Beamish, Neville & Cass 1997; Mantua,
Hare, Zhang, Wallace & Francis 1997). Typically,
salmon production exhibits dramatic increases or
decreases during decadal-scale regime periods (Fig. 5).