Potential for Predicting Plankton Populations (and Fish Recruitment) from Environmental Data

Abstract

A model of annual plankton cycles, which responds to seasonal changes in light and mixed layer depth, was driven by a 26-yr series of observed mixed layer depths. Within the model, year-to-year changes in herbivore concentration are completely determined by year-to-year changes in mixed layer depth; but a correlational study of these two variables does not reveal the dependence, especially for spring herbivore concentrations. Fish recruitment, to the extent that it depends on the timely availability of planktonic food, may be difficult to relate to environmental observations. There are, however, some weak but long-lasting correlations which adult fish may be able to use as a cue for allocating reproductive effort.