Probable loss of chlorophyll‐derived pigments during passage through the gut of zooplankton, and some of the consequences

Abstract
By use of biogenic silica as an inert marker, it is shown that chlorophyll a and its derivatives can be destroyed or absorbed during passage through the gut of a herbivorous copepod. This observation is contradictory to the hypothesis that chlorophyll a is converted to pheophorbide a with 100% molar efficiency. The currently used equations for measuring chlorophyll and pheopigment by fluorescence cannot be used to give concentration of pheopigment.