Chapter 3: Ocean Ecology of Sockeye Salmon
Edward V. Farley, Jr., Terry D. Beacham, and Alexander V. Bugaev
This chapter updates existing information on marine ecology of Sockeye Salmon Oncorhynchus nerka with new information gathered over the past two decades. For those seeking historical information on Sockeye Salmon marine ecology, the two important earlier references include the Sockeye Salmon book by Foerster (1968) and the book chapter on Sockeye Salmon in Pacific Salmon Life Histories by Burgner (1991). These earlier references discuss what was known about freshwater and marine Sockeye Salmon ecology through the 1980s. Since the mid 1990s, there has been a wealth of new information on salmon marine ecology, mostly through the efforts of government agencies who manage commercial and subsistence fisheries of salmon and collaborative international research efforts within the North Pacific Anadromous Fish Commission. The research efforts are driven by the need to understand the impact of a rapidly changing marine environment on salmon marine ecology, as salmon production in the North Pacific is extremely variable and managers are having a difficult time explaining weak or strong returns when forecast models fail. For Sockeye Salmon in particular, the failure of production models during the late 1990s for Bristol Bay Sockeye Salmon led to disaster declarations by U.S. and Alaska State governments for the Bristol Bay fishery (Kruse 1998). In addition, the collapse of the Fraser River Sockeye Salmon during 2009 (Beamish et al. 2012a) was not predicted; in response Canada spent more than Can$27 million on a commission inquiry to determine the reasons for the poor Fraser River Sockeye Salmon return. Therefore, the new information on Sockeye Salmon marine ecology is timely, given our need to understand climate impact on marine ecosystems and the response of Sockeye Salmon to these changing conditions.