Community reorganization in the Gulf of Alaska following ocean climate regime shift

P.J. Anderson; John F. Piatt

doi:10.3354/meps189117

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USGS · 70021245

Community reorganization in the Gulf of Alaska following ocean climate regime shift

P.J. Anderson·John F. Piatt

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Abstract

A shift in ocean climate during the late 1970s triggered a reorganization of community structure in the Gulf of Alaska ecosystem, as evidenced in changing catch composition on long-term (1953 to 1997) small-mesh trawl surveys. Forage species such as pandalid shrimp and capelin declined because of recruitment failure and predation, and populations have not yet recovered. Total trawl catch biomass declined >50% and remained low through the 1980s. In contrast, recruitment of high trophic-level groundfish improved during the 1980s, yielding a >250% increase in catch biomass during the 1990s. This trophic reorganization apparently had negative effects on piscivorous sea birds and marine mammals.

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P.J. Anderson, John F. Piatt. 1999. Community reorganization in the Gulf of Alaska following ocean climate regime shift. https://doi.org/10.3354/meps189117

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