PORTLAND, Ore. (KOIN) – Razor clamming is closed from Cape Blanco to the California border after officials found recent razor clam samples had unsafe levels of domoic acid, the Oregon Department of Fish and Wildlife announced Friday.

Domoic acid, a marine biotoxin, is produced by algae and originates in the ocean, officials explained. The Oregon Department of Agriculture will continue testing for the shellfish toxin at least twice per month.

Officials said razor clamming is still open from the Washington border to Tillamook Head and from Seal Rock to Cape Blanco.

Mussel harvesting and bay clamming are still open statewide, ODFW said, along with crabbing in bays and estuaries. ODFW says recreation ocean crabbing is closed through Nov. 30.