Caloric and Carbon Equivalents of Zooplankton Biomass

Abstract

In a study throughout 1 year at a station in St. Margaret's Bay, N.S., the caloric content per unit dry weight of zooplankton showed a fivefold variation. Along with all the available information from the literature, the data indicated that the dependence of caloric content of zooplankton (y) on per cent organic matter (x) could be described by the equation y = −3370 + 136 x − 0.514 x2. The caloric content may be predicted from per cent ash (A) and per cent carbon (C) by the equation y = 1351 + 106 C − 21.2 A. The relative stability of the caloric or carbon standing stock of zooplankton per unit water volume, compared with numbers or dry weight, may be an indication of some kind of regulatory mechanism controlling energy flow.