Based on an inter-species comparison across the Gulf of Alaska and eastern Bering Sea, Pyper et al. (2005) concluded that there was no evidence that basin-scale environmental processes simultaneously influenced survival rates of pink, chum, and sockeye salmon. Pink and chum salmon showed the strongest patterns of positive covariation in survival rate among the three species examined, probably related to similar life-history and ecological characteristics (Pyper et al., 2005). Pyper et al., 2001 and Pyper et al., 2005 stressed the importance of local (< 1000 km) environmental conditions for studies of mechanisms of population fluctuation and fishery management. Botsford and Lawrence (2002) reported an inverse regional relationship in commercial catch of coho salmon (Oncorhynchus kisutch); an increase in the Gulf of Alaska since the mid-1970s and concurrent declines in the California Current. They concluded that the dominant, warm/cool mode of physical co-variability, which drives these populations regionally, is related to basin-scale indices. This conclusion does not conflict with that of Pyper et al. (2005), because their target current systems are differentiated, and contrasting coho catch trends in two areas ( Botsford and Lawrence, 2002) are consistent to regional differences in primary production after the 1976/77 regime shift ( Fig. 2a ; also see Section 3.2).