Share story

The coastal razor clam season will end on a sour note after the state Department of Fish & Wildlife reported a continued sharp increase in marine toxin levels in clams.

Water samples recently collected showed the levels of domoic acid, a natural marine toxin, are still rising. If ingested by humans, the toxin can cause nausea, vomiting, diarrhea or abdominal pains. Other symptoms could include dizziness, disorientation, seizures and difficulty breathing. In a worst-case scenario the toxin affects the brain and can even be fatal.

“The party is over, and this is kind of an unremarkable end to what has been such a remarkable razor-clam season this past fall, winter and spring,” said Dan Ayres, the head state Fish and Wildlife coastal shellfish manager, who has cancelled the remaining digs that had been scheduled for May 15-17 and May 22-24.
“We are seeing high levels of the plankton species at all beach locations so chances of it going down are slim, and I’m expecting the next test samples to show even higher levels,” Ayres said. “Right now I am more concerned about the upcoming fall season than I am about the rest of this year.”

Ayres said the last round of testing showed the toxin levels at Long Beach had climbed to 60 parts per million (ppm), well above the action cutoff level of 20 ppm.

“The last time something like this occurred was in the spring of 2005 when we had a brief two-day closure at Long Beach,” Ayres said. “The last extended closure along our coastal beaches happened in 2002 and 2003.”

Domoic acid — first detected off the Pacific coast in 1991 — is caused by a single-celled plant called a diatom, and toxin builds up in the meat of the filter-feeding shellfish such as razor clams that ingest it.

Experts say a huge pool of warmer than normal water in the Pacific Ocean off the coast and extending north into the Gulf of Alaska referred to as “the blob” has water temperatures spiking up. This coupled with El Nino could have a negative effect not only on shellfish, but for other fish species such as salmon.

“The ocean water regime is shifting with El Nino concerns and warmer conditions in the ocean … we might be faced with these types of situations more often than not moving forward,” Ayres said. “Warm ocean water temperatures have created ideal conditions for the algae that produce domoic acid.”

In Oregon, health officials also announced a closure of razor-clam digging and mussel gathering on Clatsop County beaches late Friday.

Razor clams remain abundant on Long Beach, Twin Harbors, Mocrocks and Copalis beaches.

From Oct. 7 through April 24, 385,930 diggers took home more than 5.3 million clams with diggers averaging 13.3 to 14.1 clams (the first 15 clams dug, regardless of size or condition, is a daily limit).

“I hate to end it with such a negative feeling, but the good news is nobody got sick and we don’t want that to happen in what is such a good recreational activity,” Ayres said.