ECOHAB: Trophic effects of two dinoflagellates.

EPA Grant Number: R826219
Title: ECOHAB: Trophic effects of two dinoflagellates.
Investigators: McManus, George , Dam, Hans G. , Shumway, Sandra E. , Smolowitz, Roxanna M.
Current Investigators: McManus, George , Dam, Hans G. , Shumway, Sandra E. , Smolowitz, Roxanna M. , Wikfors, Gary H.
Institution: University of Connecticut , Bigelow Laboratory for Ocean Sciences , Marine Biological Laboratory , University of Pennsylvania
Current Institution: University of Connecticut , Long Island University - Southampton College , Marine Biological Laboratory , National Oceanic and Atmospheric Administration (NOAA)
EPA Project Officer: Rosenthal, Sheila
Project Period: January 15, 1998 through January 14, 1999
Project Amount: $102,514
RFA: Harmful Algal Blooms (1997) RFA Text |  Recipients Lists
Research Category: Aquatic Ecosystems , Water , Ecosystems


Most harmful algal bloom (HAB) dinoflagellates grow relatively slowly; therefore, accumulation of their biomass (a bloom) is likely attributable in large part to reduced grazing. Among the grazing organisms that normally limit phytoplankton biomass accumulation are pelagic consumers, such as protozoans, copepods, and larvae of benthic invertebrates, as well as bottom-dwelling (benthic), filter-feeders -- chiefly the bivalve mollusks. We will study the relationships among various grazers and two species of HAB algae, measuring feeding rates and potential toxic effects at a variety of concentrations and at different stages of the algal growth cycle.

Knowledge of direct, harmful effects of an algal species upon consumers would explain the mechanism by which a bloom of that alga can occur, and provide predictive capability of the types of ecosystems, dominated by benthic or pelagic consumers, that are most susceptible to blooms of that alga.


We propose to investigate systematically, under controlled laboratory conditions, effects of two cultured HAB dinoflagellates, Prorocentrum minimum and Gyrodinium aureolum, upon a suite of representative consumer organisms, including three protozoans, two copepods, and a larval and post-set bivalve. Effects of these dinoflagellates upon feeding, behavior, population dynamics, and histological condition of individual organisms will be documented. This work will benefit from a team approach utilizing, in all experiments, identical algal cultures produced in the unique Milford Microalgal Mass Culture Facility.

Expected Results:

This study will provide information critical to interpretation of field studies of HAB dynamics and food-web effects. In particular, predictions of the susceptibility of certain areas to blooms may be made more exact using the knowledge of grazer-algae interactions developed in this project.

Publications and Presentations:

Publications have been submitted on this project: View all 3 publications for this project

Supplemental Keywords:

estuary, fish kill, saxitoxin, oceanography, coastal, HPLC, RFA, Scientific Discipline, Water, Ecosystem Protection/Environmental Exposure & Risk, Ecosystem/Assessment/Indicators, Ecosystem Protection, exploratory research environmental biology, Oceanography, Ecological Effects - Environmental Exposure & Risk, algal blooms, Ecology and Ecosystems, Biology, Ecological Indicators, copecod grazing, marine ecosystem, coastal ecosystem, ecological exposure, bloom dynamics, dinoflagellates, fish kills, growth cycle, harmful algal blooms, phytoplankton, trophic effects, ECOHAB, trophic transfer of phycotoxins, dinoflagellate, benthic algae

Progress and Final Reports:

Final Report