Tribes, Sound Toxins providing predictive data for harmful algal blooms

With more than 10 years of data under their belts, Jamestown S’Klallam Tribe natural resources staff have developed a keen eye for potential algal blooms, which can affect shellfish harvesting opportunities for the tribe and the greater community.

In the 13 years the tribe has been collecting data, there have been trends of normal and abnormal phytoplankton behavior in Sequim Bay, said Neil Harrington, the tribe’s environmental biologist. When drastic events take place, such as the 2015 drought, it helps put the trends in perspective.

“The heatwave in 2015 was anomalous; we could really see it in the water (from our samples),” he said. “That was like a marine heatwave; the water was orange and super nasty. And we’re thinking, ‘Things are really out of balance and out of whack right now. Something’s going on in the water…’ and we were able to identify the phytoplankton responsible.”

Another trend has been seeing harmful algal blooms lasting late into the year.

“It’s unusual, especially compared to the records about shellfish toxicity in Sequim Bay that goes back 70 years,” he said. “There’s been a couple of times in November where we’re like, ‘Wait a second. We are not off the hook yet—we can’t start harvesting oysters yet. We still have shellfish that are unsafe to consume due to biotoxins.'”

Since 2008, as part of the region-wide Sound Toxins program, the tribe has been studying the presence of different species of phytoplankton in Sequim Bay, specifically ones that could produce harmful biotoxins that accumulate in shellfish and make people sick when eaten.

“If we see Alexandrium that causes paralytic shellfish poisoning, we get really nervous because it doesn’t take much to turn shellfish toxic,” Harrington said. “With Dinophysis, which is a single-celled algae that causes diarrheticshellfish poisoning, there can be a fair bit in the water and the shellfish aren’t toxic yet. So there’s a bit of a lag there, which is great.”

When there is a spike of certain phytoplankton in the water, the tribe increases shellfish sampling from every 10 days to weekly while putting the tribe’s shellfish farm on high alert that they may have to temporarily pause harvesting and shellfish sales. Sampling happens year-round.

This work also protects the tribal citizens who exercise the treaty right to harvest shellfish from the tribe’s subsistence beach in Sequim Bay, Harrington said.

This work is part of the Sound Toxins program, a partnership between tribes, volunteers, environmental education centers, colleges, and shellfish and finfish growers that monitor Puget Sound waters to provide early warning of harmful algal bloom events. Other tribal partners include the Makah Tribe, Nisqually Indian Tribe, Port Gamble S’Klallam Tribe, Skokomish Tribe, Stillaguamish Tribe of Indians, Squaxin Island Tribe and Tulalip Tribes.

Neil Harrington, the tribe’s environmental biologist takes a water quality sample from Sequim Bay. Story and photo: Tiffany Royal