Environmental conditions which lead to increase in cell density of the toxic dinoflagellates Dinophysis spp. in nutrient-rich and nutrient-poor waters of the French Atlantic coast

Abstract

7 stations located off La Rochelle, France, from near-shore ('bassin Marennes-Oleron') to offshore waters (50 m depth contour) were vlslted 8 times, with the aim of determining whether the toxic dinoflagellates Dinophysls spp. ~n c r e a s e In cell denslty In nutr~entpoor offshore water, in nutrient-rich Inshore waters, or both, and to determine t h e ~r vertical d~stributlon In relation to stratification Temperature stratification developed offshore, but not inshore In April, few Dinophysis spp. were present offshore and none ~n s h o r e .