Oceanographic regime shifts and tuna recruitment in the western and central Pacific Ocean
نویسندگان
چکیده
This analysis aims to establish whether the ‘regime shifts’ documented for the north Pacific Ocean are seen in the western and central Pacific Ocean (WCPO) and are relevant to recruitment variation for tropical tunas. Quantitative indicators of oceanographic state are derived by multivariate analysis of physical and biological variables output from an ocean general circulation and biogeochemical model. Tests are applied to determine the existence of statistically significant regime shifts in time series of both ecosystem indicators and tuna recruitment estimates. Shifts are found at times that are broadly consistent with other studies for the north Pacific (1976, 1989, 1998) although earlier shifts (ca. 1964) appear to be just as significant. The methods are sound for the purposes of oceanographic monitoring and analysis but are inadequate to build causal or predictive relationships between the ocean environment and tuna recruitment. Other statistical models have proved useful in that regard and the best single indicator for monitoring the effect of long-term environmental variability on yellowfin tuna recruitment appears to be the area of the western Pacific warm pool. Kirby et al.: Regime shifts and recruitment *Email: [email protected] MANUSCRIPT SUBMITTED TO CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES PLEASE DO NOT CITE WITHOUT FIRST CONTACTING THE CORRESPONDING AUTHOR
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تاریخ انتشار 2007