- Learn MoreFor a regional overview of work on harmful algal blooms (HABs) in our region, see the winter 2015 issue of our newsletter, Sea Star, and the Encyclopedia of Puget Sound’s Science Review.
A Who’s Who of HABs
Who are these critters that can erupt into harmful algal blooms? The HAB species that most worry Washington health officials include the following:
Alexandrium catenella, the so-called “red tide” dinoflagellate that causes sometimes-lethal paralytic shellfish poisoning (PSP), undergoes a dormant cyst state — lingering in bottom sediments — then erupts into blooms when conditions turn favorable. That’s traditionally been the warmer months, but blooms are now starting earlier, extending later into the year, and becoming more severe. This organism’s toxins can build up especially quickly in mussels, which filter high volumes of water, and may last a year or more in butter clams and non-native varnish clams.
Pseudo-nitzschia diatoms produce domoic acid, the toxin that causes amnesic shellfish poisoning (ASP). Its symptoms can be neurological, as well as gastrointestinal. ASP’s effects on seabirds in California inspired Alfred Hitchcock’s film, The Birds.
Dinophysis dinoflagellates cause the self-descriptive diarrhetic shellfish poisoning (DSP). Dinophysis floated for decades in local waters without apparent harm. Then, in 2011, three people came down with DSP after eating mussels from Sequim Bay. Sixty more fell sick in 2012 after eating mussels from Saltspring Island, Canada.
Heterosigma akashiwo, a raphidophyte, poisons fish rather than humans. Until 2014 it was only known to kill fish concentrated in aquacultural net pens. Then Jamestown S’Klallam tribal biologist Neil Harrington found hundreds of afflicted chum salmon washed up in Sequim Bay. Like Alexandrium, Heterosigma can hide dormant in sediments. Unlike Alexandrium, it can emerge whenever light and temperature conditions turn favorable. Heterosigma then swims rapidly to the surface and forms massive toxic blooms.
WSG staff, led by water quality specialist Michelle Lepori-Bui, use many strategies to help Washingtonians understand and guard against harmful algal blooms.
- WSG staff trained and coordinated 50 SoundToxins monitors deployed to 33 sites from Budd Inlet in south Puget Sound to Orcas Island and Port Angeles.
- WSG hosts the annual Shellfish Growers Conference.
- WSG disseminates publications to the public to help them gather safe shellfish.
- WSG conducts workshops, beach walks, site visits; hosting booths at community festivals and makes presentations to professionals and the general public.
- WSG manages Bivalves for Clean Water, a citizen science program that the uses shellfish for monitoring water quality.
- SoundToxins Manual
A guide to the SoundToxins volunteer HAB monitoring program.
- Nasty HABits
Increasingly toxic algal blooms in Washington’s waters threaten consumers, shellfish growers, fish farmers, even birds and salmon. Read how WSG field agents and researchers are deploying innovative strategies to monitor harmful algae in WSG’s Spring 2015 newsletter.
- Gathering safe shellfish in Washington: avoiding paralytic shellfish poisoning
Learn to a be safe shellfish gatherer using this classic guide by WSG researchers and staff.
WSG supports cutting-edge research into these elusive algae, developing new ways to predict and prepare for their blooms, and understand their impact on the Salish Sea ecosystem:
- HAB toxins in the food web
- Biotoxins uptake in rock scallops
- Predicting Alexandrium blooms
- Heterosigma cyst formation and longevity
- Low-cost sensor network for HABs
- Optical tools for HAB detection
In the News
- New research could lead to forecasting of future marine heat waves in the Pacific Northwest K5 News, April 28, 2022
- Estimating the benefits of an early warning system for harmful algal blooms
The Islands’ Weekly, February 12, 2021
- Funding for studying harmful algal blooms
The Islands’ Sounder, January 30, 2020
From climate mysteries to dead zones, an evolving computer model tackles Puget Sound’s eco-riddles
GeekWire, November 3, 2019
Federal grant will aid Sitka Tribe toxin research
The Cordova Times, October 13, 2019
- Rocky Bay algae bloom suspected in clam die-off
Key Peninsula News, August 1, 2019
- “Underwater forecast” predicts temperature, acidity and more in Puget Sound
UW News, February 8, 2019