Crescent Beach is a majestic place, bounded by thick forest and rocky headlands that jut from the sea, rounded and bird-covered to the south, sharp like sails to the north.

It's also, as Marc Ward has discovered, a "plastic sink," one of the spots along Oregon's coast where thousands upon thousands of plastic fragments spin out of the North Pacific Gyre and settle into high-tideline sands.

Ward, a 54-year-old Seaside native, splits his year dashing between protecting sea turtles in Costa Rica and tracking an increase of toxic-laden "microplastics" on Oregon beaches. Those two vocations are closely related, given the plastic found in the stomachs of sea turtles, seabirds and other ocean creatures.

In rubber boots, cargo shorts and a safety mask, he scoops sand from Crescent Beach onto a homemade filter -- a fiberglass net tacked between wooden dowels.

Ward and a volunteer rock it up and down, sifting sand. Left behind: bits of wood, hundreds of polystyrene flakes, industrial polymer pellets and brittle plastic fragments, tinkling like wind chimes in the swaying net.

Tossed at sea

Scientists estimate -- very roughly -- about 100 million tons of garbage in two patches within the North Pacific Gyre. Much is weathered plastic pieces floating beneath the surface, broken down consumer products and marine castoffs.

The patches sit within the gyre, which rotates clockwise off the West Coast. The north and central Oregon coast sits near a prime escape hatch: roughly 2 o'clock as the current curves down the coast.

"You guys are almost at the bullseye of a shotgun blast of debris," says Chris Pincetich, a California marine biologist and advisor to Ward's non-profit, Sea Turtles Forever.

The landfall zone extends from northern Oregon to Cape Blanco, south of Coos Bay, Ward says. In three years of beachcombing, he's found microplastic buried at every beach he's scouted from Cape Blanco north -- typically in a 15-foot-wide band near high tide lines.

He's found particularly high concentrations, or sinks, at Bandon, Manzanita, Rockaway, Oswald West, Cannon Beach and Crescent Beach. Sinks tend to form south of geological formations, Ward says, including headlands, jetties and points that create a back eddy, as Tillamook Head does at Crescent Beach. The same characteristics attract seabirds -- and beachgoers.

The plastic, from nickel to sand-grain size, has likely been at sea for years, breaking down under ultraviolet rays but not biodegrading.

At the sinks, Ward marks off square meters for sampling. He digs 5 centimeters down, sifts, then counts and weighs the plastic in his garage lab.

Ward first noticed microplastics on Oregon beaches four years ago. Three years ago, he saw the biggest surge, and figures a combination of critical plastic mass in the ocean and changing currents fueled the deluge. Plastic in his highest-density samples has increased 30 percent a year since in spots he'd already cleaned, including a big boost in polystyrene after the 2011 Japanese tsunami.

Ward tallied more than a half-pound of plastic in one square meter at Crescent Beach this summer, including 739 styrene flakes and 861 industrial pellets. About 10 percent is visible, he says, the rest buried under drifts.

"People walk by and they think, 'Oh, we have a little problem here,'" Ward says. "They don't realize 90 percent of it is out of sight."

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