Emerging from Hjort's Shadow

Early in the 20 th century, Johan Hjort developed compelling arguments and hypotheses to explain recruitment variability that became dominant for more than 75 years. A cautious emergence from Hjort's shadow began late in the 20 th century. Hjort's "Critical Period" hypothesis, i.e., failure of first-feeding larvae to find food, and a second hypothesis, "Aberrant Drift" of eggs and larvae, were proposed to explain causes of recruitment variability. Tests of the Critical Period hypothesis became an obsession, although support for it was inconsistent and equivocal. Single-minded research on the Critical Period hypothesis gave way to realization that recruitment variability was the outcome of complex trophodynamic…

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  National Science Foundation

  Award: 0453905