The tide may be out, but the table is not always set for coastal Washington folks whose livelihoods depend on their ability to grow and harvest shellfish.
Commercial shellfish growers, tribal members and recreational clammers have all been forced to adapt to life with biotoxins, algae-derived poisons that can cause a variety of illnesses in humans, including gastrointestinal distress, paralysis, memory loss and even death.
It’s a problem that’s worsened in recent decades. Whatcom County beaches have seen shellfish harvest closures due to biotoxin every year for the last five years, and in May, recreational harvesting was closed in Drayton Harbor and Bellingham Bay due to unsafe levels of paralytic shellfish poison. Yet the threat of biotoxins is not new to human history, nor to the planet.
[ Read more: What are marine biotoxins — and what do they have to do with beach closures? ]
Biotoxins are produced by certain species of marine algae (phytoplankton) that are always in the ocean but become dangerous when they grow out of control. Fossils of birds and mammals found alongside those of algal blooms suggest that biotoxins have been responsible for animal deaths as early as 47 million years ago.
Human history is also rife with evidence of algal blooms. It’s theorized that the story of the Nile turning to blood described in the Bible was really a historical account of a red algae bloom that deprived the river of oxygen and led to fish kills. Later in 1793, a member of Captain George Vancouver’s crew was reported dead from eating contaminated shellfish.
Vancouver’s account was one of the first written instances of human shellfish poisoning, but Native tribes along the Pacific Northwest have long known about biotoxins.
Misty Peacock, director of the Salish Sea Research Center (SSRC) at Northwest Indian College, said traditional Lummi knowledge often predates Western scientific understanding of what causes shellfish poisoning. For instance, butter clams are traditionally prepared by cutting off the siphon before cooking.
“If you think about the siphon of a clam … it’s the part that sticks out and sucks in the water to filter feed, [so] there can be an accumulation of algae that produce the biotoxin,” Peacock said. “And so, it’s very smart to cut off the tip of that siphon. You can actually reduce the toxic load of that clam.”
Coastal communities feel the impact
Today’s biotoxin problem is worse than that of centuries past, however. Amnesic and diarrhetic shellfish poisonings are relatively new problems on the West Coast, with monitoring by the Washington State Department of Health (DOH) only starting in 1991 and 2011, respectively, for the two toxins.
Increases in aquaculture and shellfish demand mean people are feeling the economic impacts now more than ever, while experts fear environmental shifts like ocean acidification and rising water temperatures will expand the season and types of toxin-producing harmful algal blooms. Nevertheless, commercial shellfish producers are striving to ensure their customers stay safe.
“It’s just part of what you have to do if you want to grow shellfish commercially,” said Bill Dewey, director of public affairs at Taylor Shellfish Farms and owner of his own shellfish operation in Samish Bay.
Commercial oyster and clam growers are required by law to test their beds regularly for biotoxins before sending them to market, a fact Dewey said is often overlooked by hesitant consumers.
Panic about poisoning can hurt local shellfish businesses, a cost made even worse by the steep fees of sending product samples to the state for testing: anywhere from $173 to $1,189 for paralytic shellfish poison, according to the Governor’s Office for Regulatory Innovation and Assistance.
Certain biotoxins can be toxic to shellfish too, causing losses both in wild populations and commercial farms. Ralph Solomon is the assistant manager of the Lummi Shellfish Hatchery, where thousands of oyster, geoduck and manila clam seed are produced every year, both for sale to other shellfish growers and to enrich the tribe’s clamming beaches. He said the hatchery has experienced several losses of juvenile shellfish in recent years, with biotoxins likely contributing.
“I’ve seen [the problem] grow in the last 20 years … Last year I had four crashes in a row, which set us back two months,” Solomon said. “We had to put off our geoduck spawn, too. Normally they’re out by now, but we’re three months behind.”
The hatchery still manages to produce and ship out high-quality shellfish spawn, but they’ve had to adapt. Samples of their products are sent every year to the DOH for biotoxin testing, and they’ve employed new technology, including UV lights and microfilters, to ensure seawater flowing to the shellfish larvae stays clean of biotoxin-producing algae.
The restrictions on subsistence and recreational harvesting are much harder to work around. Because the laboratory equipment required for biotoxin testing is expensive, most samples taken from Washington beaches must be sent to state labs. The state then has to balance how often they sample their own monitoring sites with the number of sites they can feasibly maintain. Put together, this means non-commercial beaches often have to stay closed for longer, because a negative test is required to reopen a beach closed for biotoxin.
It’s all in the name of keeping folks safe, but the restrictions themselves come with consequences. Solomon, who is also a Lummi tribal member, said he can’t speak for the whole tribe, but the expansion in biotoxin closures has hurt his ability to collect food in the traditional way.
“It used to be, ‘Tide’s out, table’s set,’” Solomon said. “But now I have to wait for them to test. Before, I could just go out [clamming] when I needed to eat, but now you just can’t do that every time.”
For tribal communities where shellfish have an important place in ceremonies as well as on the table, there’s not a simple solution to the problem. Yet the network of algal biotoxin researchers continues to grow, with the hope that science will be able to help alleviate what for many is a growing burden.
Adapting to life with biotoxins
As the only stand-alone marine research center in the tribal college system, the SSRC focuses its work on ensuring Native peoples along the coast have access to safe seafood. They sample shellfish up and down the Salish Sea coastline, targeting those that are frequently subsistence harvested, like butter clams. There’s also a heavy emphasis on education, with paid internships offered every year at the research center for tribal students interested in marine sciences.
North of the Lummi reservation in Birch Bay and Semiahmoo, another group of citizen scientists is working with the larger network of phytoplankton monitors known as SoundToxins to further improve the state’s biotoxin monitoring system. They call themselves the Drayton Harbor HAB [Harmful Algal Bloom] Hunters, and their goal is to identify harmful algal species in local waters before they bloom. Their method requires only a water sample, a microscope and a trained eye, so it’s a lot quicker and cheaper than sending samples to a lab.
Rick Beauregard, chief organizer for the small group, said the HAB Hunters (who are all volunteers) came together to address a gap in biotoxin monitoring in their community.
“When I looked at the sites [SoundToxins] was monitoring at the time, I saw that there were none in northern Whatcom County,” Beauregard recalled. “And given that we had commercial shellfish harvesting going on in Drayton Harbor and how important that was … I contacted SoundToxins [to] adopt our site.”
Unfortunately, COVID and funding difficulties made it impossible for SoundToxins to officially adopt the Birch Bay and Semiahmoo sites right away.
“But we went ahead and did the sampling anyway,” Beauregard said. “I started a GoFundMe page and we raised a couple thousand dollars to buy some microscopes and field equipment … and we just started sending our data to SoundToxins … A couple years later, they added us to their official site list.”
The HAB Hunters, along with other phytoplankton monitoring groups, work in parallel with the DOH to inform which sites need additional testing and which might be ready to open back up to shellfish harvesting earlier than expected. Together with the more definitive lab tests, the monitoring efforts help ensure beaches close as soon as biotoxins reach unsafe levels — and that restrictions on harvesting don’t stay active longer than they need to be.
The future of biotoxins remains cloudy amid concerns over harmful algal blooms and a rapidly changing ocean, but the dedication of folks on the Washington coast to monitoring and research paints a picture of resiliency, not fear.
Hope remains that the tide will continue to bring its bounty to the table for centuries to come.
Ben Long is an environmental/science reporter, placed at CDN through the American Association for the Advancement of Science (AAAS) Mass Media Fellowship. Reach him at benlong@cascadiadaily.com.
