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An Early Warning System for Pseudo-nitzschia Harmful Algal Blooms on Pacific Northwest Outer-Coast Beaches

This project began in 2016 and is projected to be completed in 2022

Blooms of some species of the diatom Pseudo-nitzschia produce a neurotoxin that accumulates in shellfish, which can cause illness and even death in humans who eat them. Shellfish managers monitor these toxins and close affected fisheries to protect public health, but these sudden closures can disrupt coastal economies. Using predictive models and toxin monitoring data, we are developing a system that will forecast when and where blooms of Pseudo-nitzschia will affect shellfish harvests.

Why We Care
Razor clams support tens of millions of dollars annually in coastal tourism in Oregon and Washington and are essential to Olympic coast tribal nations as a culturally and nutritionally significant food source, a means of income, and a valuable commercial commodity. Razor clams are also a key prey item for Dungeness crab. The commercial Dungeness crab fishery is the most valuable single-species fishery in the state of Washington (worth roughly $84 million annually) and the top fisheries employer in Oregon.

Some species of Pseudo-nitzschia produce domoic acid, a potent neurotoxin that can accumulate in shellfish, other invertebrates, and sometimes fish, leading to illness and death in a variety of seabirds and marine mammals. Human consumption of shellfish contaminated with domoic acid can result in amnesic shellfish poisoning, which, if not treated, can be life threatening.

Along the Washington coast, razor clams and Dungeness crabs are particularly likely to accumulate domoic acid. States and tribes close affected areas to ensure shellfish are safe to eat. While critical for public health protection, these closures disrupt the economies of coastal communities in Oregon and Washington reliant on recreational and commercial shellfish. This project will help improve fisheries regulations and support management decisions that protect our health, our seafood supply, and our ocean environment.

What We Are Doing
We are developing a monitoring- and modeling-based forecast system for blooms of the diatom Pseudo-nitzschia and particulate domoic acid on beaches from Cape Flattery, Washington, to Heceta Head, Oregon. The project team will use data on particulate domoic acid in both the water and in razor clams available through Washington and Oregon surf-zone and shellfish monitoring programs. The team will also institute new, low-cost harmful algal bloom (HAB) monitoring for offshore HAB “hotspots” such as the Juan de Fuca Eddy and Heceta Bank through partnerships with the Makah Tribe, Olympic Region Harmful Algal Bloom (ORHAB) program, and the NOAA Northwest Fisheries Science Center.

We will also reinstate and improve the spring-to-autumn Pacific Northwest HAB Bulletin, last generated in 2011, to provide managers with summaries of when and where coastal blooms are likely to occur. The new Pacific Northwest HAB Bulletin will incorporate expert analysis and draw on the latest University of Washington LiveOcean forecast model hosted by the Northwest Association of Networked Ocean Observing Systems (NANOOS) and a variety of real-time observations. We will improve the phytoplankton model embedded in LiveOcean to reduce false positives in forecasts of Pseudo-nitzschia and particulate domoic acid beach events.

Finally, we will determine the optimal means for incorporating LiveOcean transport forecasts and hindcasts into the bulletin to understand model skill and error in detail and develop a basis for semi-automation of the bulletin. We will also explore ways to share the bulletin with managers via NANOOS.

Benefits of Our Work
Nearly every year, HABs have some negative impacts on the economies of coastal communities in Washington and Oregon dependent on shellfish harvesting. These communities rely on the thousands of people who come to the coast to harvest their recreational limit of clams. Occasionally, as in 2015, the entire region experiences a major HAB event that forces closures of both razor clam and Dungeness crab seasons.

This project will benefit coastal communities in the Pacific Northwest. Our results will lead to improved fisheries regulations and support frequent management decisions to protect public health, the seafood supply, and the ocean environment. Timely forecasts will help make recreational harvests safer and worry free, and help minimize economic impacts by supporting targeted fishery closures. This project builds on more than a decade of NOAA and partner-funded research, and will help demonstrate how to routinely generate HAB forecasts valued by the region. Shellfish managers will come to rely on HAB forecasts to better ensure seafood safety while reducing economic losses, much like farmers currently use weather forecasts. Improvements in predictive models and forecast dissemination will also help efforts to tackle other issues such as hypoxia and ocean acidification.

Led by scientists at the University of Washington’s Joint Institute for the Study of the Atmosphere and Ocean, the NOAA Northwest Fisheries Science Center’s (NWFSC's) Marine Biotoxins Program, and the Oregon Department of Fish and Wildlife, the project team also includes researchers from the University of Washington, the University of Strathclyde, and the University of California–Santa Cruz. This project is part of the NCCOS Monitoring and Event Response for Harmful Algal Blooms (MERHAB) program.

This pilot project has been supported largely by NOAA NCCOS grants to University of Washington and Oregon Department of Fish and Wildlife and in partnership with the Olympic Region Harmful Algal Bloom Partnership (ORHAB), the Washington Department of Health, the Washington Department of Fish and Wildlife , the Makah Tribe and NOAA Fisheries. NCCOS grant support for this project runs through 2022. The US Integrated Ocean Observing System has provided additional support to the University of Washington, the Northwest Association of Networked Ocean Observing Systems and NOAA Fisheries. Efforts are underway to transition the Bulletin to operations at NANOOS to ensure continued delivery of trusted PNW HAB Bulletin forecasts to managers.

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Peer-Reviewed Publications

Barth, John A., Susan E. Allen, Edward P. Dever, Richard K. Dewey, Wiley Evans, Richard A. Feely, Jennifer L. Fisher, Jonathan P. Fram, Burke Hales, Debby Ianson, Jennifer Jackson, Kim Juniper, Orest Kawka, Deborah Kelley, Jody M. Klymak, John Konovsky, P. Michael Kosro, Alexander Kurapov, Emilio Mayorga, Parker MacCready, Jan Newton, R. Ian Perry, Craig M. Risien, Marie Robert, Tetjana Ross, R. Kipp Shearman, Joe Schumacker, Samantha Siedlecki, Vera L. Trainer, Stephanie Waterman, and Christopher E. Wingard. 2019. Better Regional Ocean Observing Through Cross-National Cooperation: A Case Study From the Northeast Pacific. Frontiers in Marine Science. https://doi.org/10.3389/fmars.2019.00093

Stone, Hally B., Neil S. Banas, Parker MacCready, Raphael M. Kudela and Bridget Ovall. 2020. Linking Chlorophyll Concentration and Wind Patterns Using Satellite Data in the Central and Northern California Current System. Frontiers in Marine Science 7 (551562), https://doi.org/10.3389/fmars.2020.551562

Trainer, Vera L., Stephanie K. Moore, Gustaaf Hallegraeff, Raphael M. Kudela, Alejandro Clement, Jorge I. Mardones, and William P. Cochlan. 2019. Pelagic harmful algal blooms and climate change: Lessons from nature’s experiments with extremes. Harmful Algae. https://doi.org/10.1016/j.hal.2019.03.009

Trainer, Vera L., Kudela, Raphael M., Hunter, Matthew V., Adams, Nicolaus G., and McCabe, Ryan M. 2020. Climate Extreme Seeds a New Domoic Acid Hotspot on the US West Coast. Frontiers in Climate. https://doi.org/10.3389/fclim.2020.571836

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