Orange bloom holds no doom

People driving by Holmes Harbor recently might have done a double take after an iridescent orange sheen on the water caught their eyes.

According to Kathleen Parvin, an environmental health specialist for the Island County Health Department, the reddish-orange water was a bloom of algae that is present in the water of Holmes Harbor.

“It is most likely not toxic,” she said. “This is most likely a bloom of Noctiluca.”

The species that bloomed in Freeland was just one of approximately 10,000 known types of algae, according to Parvin. Only 40 of those 10,000 are known to be toxic to humans.

According to Parvin, the orange bloom is typically an annual occurrence that takes place in late spring or early summer. While the algae lives in the harbor, the changing season and sunlight can make the bloom into a murky, reddish-orange reminiscent of tomato soup.

“We usually have the orange tide in Holmes Harbor in May or June,” she said. “It’s very spectacular.”

Shellfish harvesters should always check the state Marine Toxin Hotline before heading out with their buckets, Parvin said. The color or lack of unusual color of the water is not a good indicator of whether the shellfish are safe to eat, as some harmful algae could be present but not visible.

“Anyone that collects should be cautious no matter what the color,” Parvin said.

The orange tide is not considered unsafe for humans or fish species, but is often mistaken for the harmful red tide, Parvin explained. Red tide — also known as paralytic shellfish poisoning (PSP) — can accumulate into unsafe levels in shellfish. Animals that are likely to carry the PSP disease include clams, mussels, oysters, geoduck and scallop and can cause serious illness to those who eat them. Crab meat is considered edible, but harvesters should throw away the crab’s guts and clean the crab thoroughly.

“Algaes are always out there,” Parvin said. “They’re going to bloom when the condition’s right.”

For more info

To learn more about Noctiluca algae visit the Northwest Fisheries Science Center’s Web site at; the state’s Department of Health Web site at; the state’s Department of Fish and Wildlife Web site at; or the Puget Sound Action Team’s Web site at Call the state’s Marine Biotoxin Bulletin at 800-562-5632 for more information about beach closures.

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