Northwest Fisheries Science Center

Forecasting Pseudo-nitzschia blooms

Project background

The neurotoxin domoic acid (DA), produced in Pacific Northwest (PNW) coastal waters by blooms of the diatom Pseudo-nitzschia (PN), bioaccumulates in razor clams and other shellfish, causing amnesiac shellfish poisoning if consumed. Razor clams support tens of millions of dollars annually in coastal tourism, and are essential to the Quinault Indian Nation and other Washington tribes for subsistence and commercial income. This proposal supports the development of a monitoring- and modeling-based forecast system for PN and particulate DA (pDA) on beaches from Cape Flattery, WA, to Heceta Head, OR, in partnership with existing Washington and Oregon monitoring programs,

This project, titled “MERHAB: An early warning system for Pseudo-nitzschia HABs on Pacific Northwest outer-coast beaches” is part of NOAA’s Ecological Forecasting Effort and includes a plan to transition the Pacific Northwest HAB Forecasting Bulletin from research to operations.

For more information, see: development-pacific-northwest/


N. S. Banas (co-lead), University of Strathclyde, Glasgow, Scotland
R. M. McCabe (co-lead), Joint Institute for the Study of the Atmosphere and Ocean, UW
B. M. Hickey and P. MacCready, School of Oceanography, UW
R. Osborne, Olympic Natural Resources Center, UW
V. Trainer, Northwest Fisheries Science Center
M. Hunter, Oregon Department of Fish and Wildlife
R. M. Kudela, Department of Ocean Sciences, UC Santa Cruz

Program Contact

Vera Trainer, NWFSC Marine Biotoxin Program
Marc Suddleson, Program Manager NCCOS MERHAB program


NOAA National Centers for Coastal Ocean Science (NCCOS) Monitoring and Event Response to Harmful Algal Blooms ( MERHAB) program (Sept 1, 2016 – August 31, 2021)


Trainer, V. L., S. K. Moore, G. Hallegraeff, R. Kudela, A. Clement, J. Mardonez. 2019. Pelagic harmful algal blooms and climate change: lessons from nature’s experiments. Harmful Algae.

Barth, J.A., Allen, S.E., Dever, E.P., Dewey, E.P, Dewey, R.K., Evans, W., Feely, R.A., Fisher, J.L., Fram, J.P., Hales, B., Ianson, D., Jackson, J., Juniper, K., Kawka, O., Kelley, D., Klymak, J.M., Konovsky, J., Kosro, P. M., Kurapov, A., Mayorga, E., MacCready, P., Newton, J., Perry, R.I., Risien, C.M., Robert M., Ross, T., Shearman, R.K., Schumacker, J., Siedlecki, S., Trainer, V.L., Waterman, S., Wingard, C.E. 2019. Better regional ocean observing through cross-national cooperation: a case study from the northeast Pacific. Front. Mar. Sci.

Adams, N.B., Schwenke, P., Smith, G.J., Trainer, V.L. 2017. Microsatellite markers for population genetic applications in the domoic-acid producing diatom, Pseudo- nitzschia australis Frenguelli (Bacillariophyceae). Protist. 168: 197-205.

McKibben, M., Peterson, W., Wood, A.M., Trainer, V.L., Hunter, M., White, A.E. 2017. Climatic regulation of the neurotoxin domoic acid. Proc. Nat. Acad. Sci. doi:10.1073/pnas.1606798114

McCabe, R.M., Hickey, B.M., Kudela, R.M., Lefebvre, K.A., Adams, N.G., Bill, B.D., Gulland, F.M.D., Thomson, R.E., Cochlan, W.P., Trainer, V.L. 2016. An unprecedented coastwide toxic algal bloom linked to anomalous ocean conditions. Geophysical Research Letters. 43: doi:10.1002/2016GL070023

Stern, R., S. K. Moore, V. L. Trainer, B. D. Bill, A. Fischer, S. Batten. 2018. Spatial and temporal patterns of Pseudo-nitzschia genetic diversity in the North Pacific Ocean from the Continuous Plankton Recorder survey. Marine Ecology Progress Series, 606:7-28.

Giddings, S. N., P. MacCready, B. M., Hickey, N. S. Banas, K. A. Davis, S. A., Siedlecki, V. L. Trainer, R. M. Kudela, N., A. Pelland, Connolly, T.P. 2014. Hindcasts of potential harmful algal bloom transport pathways on the Pacific Northwest coast, J. Geophys. Res. Oceans. 119: 2439–2461. doi:10.1002/2013JC009622.