Copepod Production on the Scotian Shelf based on Life-History Analyses and Laboratory Bearings

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Abstract
We estimated monthly and annual production of 10 copepod species (> 99% of copepod biomass) from Emerald Bank, Scotian Shelf, by use of numerical and weight changes between samples for Calanus spp., and by applying daily growth rates based on stage durations and weight increments between stages for others. Of these others, stage durations were estimated from generation intervals inferred from samples of Metridia lucens, Pseudocalanus newmani, and Oithona similis. For species without evident cohorts, notably Centropages typicus and Paracalanus parvus, we used published temperature-dependent durations. Production in dry weight was estimated as ca. 0.44 g∙m−3∙yr−1 (39 g∙m−2∙yr−1), with peaks in May (largely Calanus spp.) and September (largely C. typicus, P. parvus, and other warm-water forms). All species except C. finmarchicus and O. similis had annual rates 2–4 times those predicted by the Banse-Mosher allometric relationship between production/biomass ratios and adult body mass. This deviation is not attributable to assumptions in our analyses. Annual copepod production is broadly similar to recent estimates by others using similar methods for Georges Bank, Passamaquoddy Bay, N.B., and the North Sea.