Revisiting the influences of parent stock, temperature, and predation on the recruitment of the Northeast Arctic cod stock, 1930-1990

The data sets required for constructing age-based models for the Northeast Arctic cod stock are extended back to 1930 and critically reviewed. The full data set (1930–1994) is interpreted by both a standard virtual population analysis (VPA) and a version that allows for cannibalism. The resulting ex...

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Bibliographic Details
Published in:ICES Journal of Marine Science
Main Authors: Pope, John, Large, Philip, Jakobsen, Tore
Format: Text
Language:English
Published: Oxford University Press 2001
Subjects:
Online Access:http://icesjms.oxfordjournals.org/cgi/content/short/58/5/967
https://doi.org/10.1006/jmsc.2001.1100
Description
Summary:The data sets required for constructing age-based models for the Northeast Arctic cod stock are extended back to 1930 and critically reviewed. The full data set (1930–1994) is interpreted by both a standard virtual population analysis (VPA) and a version that allows for cannibalism. The resulting extended time-series of population abundance-at-age is used to reconsider the parent stock, temperature, and predation relationships described earlier. Results from the version of the VPA with cannibalism based on the new data confirm the earlier findings that temperature and spawning-stock biomass had a significant positive effect on recruitment. This is not the case with the extended time-series as interpreted by the standard VPA because, while significant temperature and juvenile predation effects are still found, a parent stock effect is no longer statistically significant. Moreover, the general level of explanation provided by the multiple regression is far less with the extended time-series.