Preliminary Modeling and Observational Studies of the Juan de Fuca Eddy

Michael Foreman¹, Barbara Hickey², Vera Trainer ³, Amy MacFadyen², and Emanuele Di Lorenzo⁴

1 Institute of Ocean Sciences, Sidney B.C., V8L 4B2, Canada. E-mail: foremanm@dfo-mpo.gc.ca
2 School of Oceanography, University of Washington, Seattle, 98195-07940, USA
3 Northwest Marine Fisheries Service, NOAA, Seattle, 98122-2013, USA
4 Scripps Institution of Oceanography, La Jolla, 92093-0224, USA

Recent studies suggest that the Juan de Fuca Eddy, a seasonal nutrient-rich retentive feature off the Washington and British Columbia coasts, may be an initiation site for the toxigenic phytoplankton Pseudo-nitzschia (PN) that impact shellfish along the Washington coast. ECOHAB PNW, a project funded by the Ecology and Oceanography of Harmful Algal Blooms program, has just completed its first year and in this talk we will describe preliminary circulation modelling results and physical oceanographic observations collected during a cruise(s) in June 2003. The particular objectives of these components of the project are a better understanding of: a) the physical factors that make the Juan de Fuca Eddy more viable for growth and sustenance of toxic PN than the nearshore upwelling region; and b) possible transport pathways between domoic acid initiation sites in the eddy and shellfish beds along the coast.