The quahaugs of Sengekontacket lie unmolested this morning, lucky survivors of a mass taking carried out in the 48 hours prior to a summer-long closure of the pond which began Monday.

On Sunday morning Edgartown clammer Manny Jardin was pulling out quahaugs as fast as he could plant his rake.

“Hear that? That rock? Maybe it’s a rock. So you scrape,” Mr. Jardin coached as he sifted through bottom of Anthier’s Pond just east of the Big Bridge. “And . . . voila.”

He tipped two hefty chowders into his floating basket.

“Simple Simon,” he declared.

The vast pond which stretches from Edgartown to Oak Bluffs and is separated from Nantucket Sound by Beach Road, was dotted with people sporting waders, rakes and clam baskets waist deep in the water throughout the weekend.

“This is the best place to clam,” said David Oliver over at the Oak Bluffs end. He has been digging the pond for more than 20 years and relies on his takings for at least one meal a week for him and his family.

“My wife will probably make a clam linguini or some littlenecks in the half shell,” he said. “But you can make clams casino, stuffers, all kinds.”

To illustrate his point Mr. Oliver produced a knife and shucked a sweet clam straight from the basket.

“It’s good therapy out here it’s nice and quiet,” he said. “I’m doing very good today.”

But after this week Mr. Oliver will take his clam rake and basket to Lagoon Pond in Vineyard Haven, and Mr. Jardin also will go elsewhere — as a senior citizen he is permitted to clam for free at Katama Bay and Cape Pogue.

But they agreed: nothing compares to the shellfishing ease and bounty offered up by Sengekontacket.

Bacteria counts tracked in 2007 by the Division of Marine Fisheries in an annual spot check showed high levels of coliform bacteria, an indicator of the presence of fecal matter in the pond, sufficient to trigger conditional approval status for the pond.

The designation made by the National Shellfish Sanitation Program requires Sengekontacket to close to shellfishing from June through September. It triggered an automatic three-year seasonal closure.

The closure had some weekend clammers, including Jerry Slattery, nonplussed.

“You’ve got these Canada geese [expletive deleted] in the pond, but they’d be doing that whether or not we were here. Someone smarter than me’s making the decisions,” said Mr. Slattery, as he hauled a brimming basket of clams into the back of his truck.

“These are very heaped bushels. A little more today,” he said with a grin.

It is unclear how much more clued in the experts are. The question is, where and what does the fecal bacteria come from?

The results of a study submitted to Edgartown shellfish constable Paul Bagnall in April by Dr. Stephen H. Jones of the University of New Hampshire identify several sources for the coliform.

Of the six contaminated samples obtained, two contained fecal matter from cormorants, three from geese, one from unknown birds and one from septage. Septage refers to effluent produced by septic tanks.

Ironically, though, the fact that the pond was cleaner in terms of coliform bacteria last year makes progress more difficult, said Oak Bluffs shellfish constable David Grunden.

“We had difficulty getting enough samples last year because the pond was cleaner. We can’t identify one principal source [of contamination],” he said.

Mr. Grunden helped supervise a project to discover an overarching cause by volunteers from the Friends of Sengekontacket, a private nonprofit dedicated to study and advocacy for protecting the pond.

“They go around every inch of the pond looking for a smoking gun,” Mr. Grunden said. “Some road runoff was detected and certainly birds are part of it but they’re not the only answer. Perhaps a number of things aligned in 2007 to produce an unusually high level.”

There are limits as to what can be done about the birds. Some egg addling has gone on, said Mr. Grunden, but Canada geese are protected under the migratory birds act, even though the Vineyard birds are no longer migratory.

Even if its source cannot be conclusively identified, the waste can be diluted through improved circulation from dredging the pond. Edgartown removed several thousand cubic yards of sand from Major’s Cove from the end of the pond in a dredging project last year, and Oak Bluffs voters allotted $500,000 in funding for dredging projects in the coming year, including Sengekontacket. The committee has also applied for a possible alternative source of funding, but either way Mr. Grunden said the Oak Bluffs end of the pond will be dredged this year.

Meanwhile, beyond the fact that it results in closure, coliform pollution is not that big of a problem, said Mr. Grunden. He said the state thresholds are extremely conservative.

“They have to consider the threat posed to, say, an immuno-compromised child,” he said.

In an ironic twist, both towns will be introducing polluted clams to the pond in the coming weeks, imported from Taunton. The shellfish are brought to the Vineyard to be cleansed in the relatively fresh Island water.

More relevant is the pond’s nitrogen pollution, which can come from a number of sources including septic systems, groundwater run off and acid rain.

The nitrogen which produces algae blooms which in turn kill shellfish, has been at capacity levels for the past several years.

Mr. Oliver, a retired U.S. Air Force pilot and one of the last clammers out on the pond Sunday, lamented the development he has tracked around the pond over the past 21 years.

“You have people living in big homes, and septic systems seep down here,” he said. “It’s a delicate balance and the balance is off kilter, it’s sad. We don’t respect it like the Indians did, there was never any problem back then.”

For now the quahaugs may have algae blooms and spider crabs to contend with, but until October at least, they will be spared the clammer’s rake. Which, pointed out Mr. Bagnall, means more clams for year-rounders.

“One thing about clams,” said the constable. “If you leave them alone, they tend to make babies.”