Interactions between red tide microalgae and herbivorous zooplankton: the noxious effects of Gyrodinium corsicum (Dinophyceae) on Acartia grani (Copepoda: Calanoida)

Gyrodinium corsicum is a dinoflagellate responsible for recurrent water discolourations during winter in Alfacs Bay (Ebre River delta, NW Mediterranean). Since first detected in 1994, episodic mortality of mussels and fish was attributed to this organism, although no direct evidence was obtained. In order to establish the direct role of the dinoflagellate in the mortality of marine fauna, we have studied the effects of G.corsicum on a potential predator, the co-occurring planktonic copepod Acartia grani. Female A.grani were exposed to different concentrations of intact cells, and