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California Sardines: A Fishery Biologist’s History

California Sardines: A Fishery Biologist’s History. 1940’s and 1950’s – Collapse of California sardine industry seen as management failure Development of the CalCOFI program Beginning awareness of climate effects (1957 El Ni ño)

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California Sardines: A Fishery Biologist’s History

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  1. California Sardines: A Fishery Biologist’s History • 1940’s and 1950’s – Collapse of California sardine industry seen as management failure • Development of the CalCOFI program • Beginning awareness of climate effects (1957 El Niño) • 1960’s and early 1970’s – Rise of CC anchovy abundance suggests that ecology may be relevant! • Competition becomes accepted explanation • Overfishing of anchovy is proposed as a solution

  2. 1970’s (Surprises) • Collapse of Peruvian anchoveta fishery • Seen as parallel to CC sardine scenario • Sudden increase in Japanese sardines • Spontaneous, independent of management • Soutar and Isaacs’ paleosedimentary scales show long-term variability is normal and large! • Fisheries are absolved of responsibility

  3. The Paleosedimentary RecordSanta Barbara Basin • There have been periods in the pre-fishery past when sardines were scarce • Spectral analysis shows high energy in the 50-70 year range • (This figure is from a more recent analysis by Baumgartner et al. 1992)

  4. CalCOFI 1973Birth of the “Regime” Concept “ … there are probably a great number of possible regimes and abrupt discontinuities connecting them, flip-flops from one regime to another ….” “Sardines, for example, are either here or not here.” “There are internal, interactive episodes locked into persistence, and one is entirely fooled if one takes one of these short intervals of a decade or so and decides there is some sort of simple probability associated with it … organisms must respond to more than just fluctuations around some optimum condition …. Fluctuations of populations must be related to these very large alternations of conditions.”--John Isaacs (1976)

  5. Early 1980’s (A Bigger Picture) • Sardines are now abundant in Peru-Chile and Japan (Offshore!) • Increasing in California • Recognition that anchovy and sardine fluctuations appear to be synchronized on a worldwide scale

  6. FAO San José 1983 • Kawasaki’s sardine figure generated optimism • Bakun and Parrish had described the main influences on abundance and distribution • A breakthrough seemed imminent: These events are so strong and clear, we should be able to discover the mechanism

  7. Late 1980’s(Discovery: Shift Happens!) • Recognition of the “mid-70’s shift” –NE Pacific • First discovered by Venrick et al. (1987) • Trenberth (1990) later gained wide recognition • The ocean is not “stationary” (time series) • Fisheries focus moving to long-term variability • Pauly and Tsukayama (1987) describe Peru as a complicated and dynamic system • Major symposia held in Vigo and Sendai

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