Penn Cove is the sort of quiet harbor where, before daylight rises in full, sailboats stand moored and kayaks drift just beyond the reach of lapping waves. Seabirds travel by, and kelp forests reach to the surface.

The cove, bordering Saratoga Passage on the eastern shore of Whidbey Island, is home to many thousands of mussels — salty, blue bivalves, clustered on dock pilings and washed up onshore.

Growing up near the cove, one unassuming stretch was often known as mussel beach. There, instead of sand or rock, the shore was covered in mussel shells.

I’m reminded of mussel beach while exploring Willapa Bay, where pearl-white oyster shells are piled high in meadows and beside parking lots. This estuary’s pristine waters are historically home to a changing yet thriving oyster population, a celebrated regional delicacy.

But abundant numbers of mussels, too, grow on the Oregon and Washington coasts. Just wander along the rocky shore at low tide to find them in dense clusters. The region is home to two mussel species – bay mussels, which grow to about three inches in length, and California surf mussels, which can reach as long as seven inches.

Fall marks the beginning of mussel season. In time, harvesting of the shellfish has now reopened along North Coast shores, following an extended closure. So check local harvesting limits, then find your mussel beach.