1 Boring Old Man

Moon snail onslaught devastates Maine clam flats
Associated Press
By CLARKE CANFIELD
Jun 23, 2010

Out on the mud flats in the easternmost nook of the United States, generations of clam diggers have dug deep into the muck for tasty soft-shells to satisfy New Englanders’ cravings for steamers and fried clams. These days, the digging isn’t so good. The clam harvest in far eastern Maine has dropped sharply in recent years, and clam diggers say one big reason is an onslaught of the carnivorous moon snail.

The little-known mollusk that drills into clams and other shellfish and eats the meat inside has been multiplying. The besieged clam population has fallen, leaving diggers with fewer clams for the taking. The snail sounds almost unreal: Mucous-oozing creatures emerging from the mud in the dark of night, drilling their way into unsuspecting clams with sandpaper-like tongues and leaving behind empty shells. "It’s like science fiction," said Brian Beal, a marine ecology professor at the University of Maine-Machias who’s studied clams and snails for decades.

Clam diggers aren’t happy.

For 30 years, Bob Varney, 55, has earned an honest day’s pay on Lubec’s flats by pulling his four-pronged clam rake over and over through the mud, clay and sand in search of the sweet "piss clams," so named because they squirt water through their necks at clammers walking by. The work is difficult and dirty, bringing barely $50 a day. These days, Varney typically harvests 55 to 60 pounds in four or five hours. Not long ago, he could rake up double that, but the clams are spread thin nowadays. A growing number have deadly drill holes in their shells from the moon snails.

What concerns him most are the snails’ volcano-shaped egg cases — some of which can hold more than 1 million eggs — that show up nearly everywhere he digs. "We didn’t have anything like this even two or three years ago," Varney said, taking a break from digging. "They’ve just escalated." Moon snails are native to the region, ranging from Canada’s Gulf of St. Lawrence to North Carolina. In Maine, their numbers go in cycles from area to area; biologists say there was a surge in the 1970s and ’80s.

For now, there’s no concern that the creatures will spread in abundance beyond far eastern Maine, one of the most productive clamming areas in Maine and New England. Thirty miles away, clam diggers don’t even have an inkling about the snails, Beal said… That’s bad news in a region where jobs are scarce and many make their livelihood from the land and the sea… Clam harvests fluctuate, but the downturn has been severe in Cobscook Bay, a sprawling body of ocean water tucked against the Canadian border, known for its 20-foot tides, turbulent waters and rich ecosystem. The harvest in Lubec and other bay towns fell by 85 percent from 2006 to 2009 — from about 800,000 pounds to about 100,000 — according to the Maine Department of Marine Resources.

Partly to blame for the decline are widespread outbreaks of "red tide," caused by a naturally occurring algae that produces a toxin that makes clam harvesting off limits, Beal said. But the rise of moon snails is the No. 1 reason. On a recent day on a Lubec flat, Beal and some clammers found dozens and dozens of the snails and their small egg cases, which look like small pieces of rubber littered on the mud. Harmless-looking and slow-moving, the creatures can turn deadly when they get hold of a clam under the mud, enveloping it with its slimy, mucous-oozing foot and softening the shell with an enzyme secretion. In just a day, they can drill a hole in the softened shell and eat the clam meat inside…