The migration of shorebirds, an annual rite of spring, is under way, and nowhere in Washington is it more spectacular than in the Grays Harbor Estuary.

Some 100,000 birds are expected in the area this week, easily visible from a boardwalk trail at the Grays Harbor National Wildlife Refuge, built for viewing dunlin, Western sandpipers, short-billed Dowitchers and more.

Peregrine falcons and merlins spark a spectacular show, as the shorebirds move simultaneously by the thousand to evade them, the flock flashing white, then gray as the birds turn.

Arriving from as far south as Argentina, the birds are drawn to the rich mudflats of the Grays Harbor Estuary, home to as many as 55,000 tiny crustaceans per cubic meter of mudflat. When the birds arrive, they do nothing but eat and sleep for two to four days before pushing on to their breeding grounds in the Arctic.

They may travel as far as 15,000 miles, round trip, each year.

The best time to see the birds is two hours before high tide, which pushes the birds ever closer to the viewing area at the refuge. Wear comfortable shoes. Binoculars or a spotting scope are a plus. Dogs are not allowed.

The boardwalk is accessible to disabled visitors. It's about a two-mile journey from one end to the other. The refuge, open daily until dark, is on the west side of Highway 109, between Hoquiam and Ocean Shores, off Paulson Road. From Paulson Road, turn right on Airport Road.

— Lynda Mapes, staff reporter