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. © 2006, Copyright Taylor & Francis Group, LLC.