We investigated the population ecology of toxigenic diatoms within the genus Pseudo‐nitzschia on the Pacific Northwest coast during 2003, 2004, and 2005. Pseudo‐nitzschia spp. were widespread and abundant across the region, and the maximum density reached at our experimental stations was ~7 × 10 6 cells L ‐1 . Pseudo‐nitzschia spp. biomass did not correlate with total phytoplankton biomass, indicating that the growth response...

It has been hypothesized that phosphate limitation, classically indicated by NO 3 : PO 4 ratios >16, is one of the critical factors allowing the coccolithophorid Emiliania huxleyi to bloom. This hypothesis is based on physiological studies showing that E. huxleyi has an exceptionally high affinity for orthophosphate and is able to use organic phosphate. Indeed, E. huxleyi has been found to bloom at high NO 3 : PO 4 ratios in s...

Cellular carbon and nitrogen content and cell volume of nutritionally and morphologically diverse dinoflagellate species were measured to determine carbon to volume (C:vol) and nitrogen to volume (N:vol) relationships. Cellular C and N content ranged from 48 to 3.0 × 10 4 pgC cell −1 and 11 to 2,656 pgN cell −1 for cells ranging in volume from 180 to 2.8 × 10 5 µm 3 . C and N density in dinoflagellates decreased significantly...