Photo 1: Valves of Pacific Razor Clam. (Photo taken at Schooner's Cove)
Pacific Razor Clam: Siliqua patula
These shells are extremely common on the surf-swept outer coast sandy beaches. The shells are extremely elongate and the live ones are covered entirely (usually) with a tan-brown periostracum, though the periostracum may be worn off of shells washed ashore.
Pacific Razors Clams are prolific breeders. Breeding is triggered by changes in water temperature when the water warms between May and September. The sexes are separate in razor clams. Females and Males release their eggs and sperm into the water.
They feed on plankton filtered from their surroundings.
References: Alaska Department of Fish and Games.