Is the lower Hudson-Raritan estuary a suitable habitat for Gonyaulax tamarensis?

Abstract

The toxic dinoflagellate Gonyaulax tamarensis Lebour (= Protogonyaulax tamarensis (Lebour emend. Taylor) Taylor = Alexandrium tamarense (Lebour) Balech) has not been identified in the lower Hudson-Raritan estuary, a characteristically hypertrophic, contaminated system but is widespread and sometimes abundant in nearby Long Island, New York waters. The authors' hypothesis is that anthropogenic contaminants can be important regulators of G. tamarensis in the Hudson-Raritan estuary. To address this, they conducted a series of bioassays of water collected from 2 locales in Lower New York Bay during July through September, the usual period of flagellate maxima. In the assays, G. tamarensis growth regulation by nitrogen, phosphorus and vitamins was relatively unimportant, less important than that of one or more components of a metals mix. Nitrogen had a primary limiting role or shared primary importance with other enrichments in just 7 and 18% of the assays, respectively; phosphorus and vitamins were less limiting.