Links between climate and recruitment of New Zealand hoki (Macruronus novaezelandiae) now unclear

Abstract

We investigated the relationship between climate variation and year‐class strengths for hoki ( Macruronus novaezelandiae ) in New Zealand waters. Our analyses extended those of a previous study, by using an additional 6 years’ data and considering some additional predictands (total year‐class strength and proportion migrating) relating to an alternative stock‐structure hypothesis, and also updated them, by using revised versions of some predictors and year‐class strengths. Predictors considered were based on the Southern Oscillation Index, weather patterns, sea‐surface temperatures, wind speeds, and modelled mixed‐layer depths and nutrient concentrations. In contrast to the earlier analyses we found little or no predictive power for either year‐class strength or proportion migrating. The substantial correlations found in the earlier study were greatly reduced. Such reversals are not uncommon in the climate‐recruitment literature.

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