In a 1952 aerial photograph of Sengekontacket Pond that hangs behind the door to Augustus Ben David’s World of Reptiles And Birds in Edgartown, you can count two properties — the one you’re standing in and the Felix Neck Wildlife Sanctuary. Today Mr. Ben David estimates that the homes clustered along the shoreline number in the thousands. “The highest point of land is the Edgartown-Vineyard Haven Road,” said the noted Vineyard naturalist and wildlife expert, “and from there everything slopes down.” Some human impact on the surrounding environment is inevitable, Mr. Ben David said. Whether or not it is affecting the clams and scallops of Sengekontacket remains to be seen.

Bacterial contamination of Sengekontacket pond led to closures this summer and, with fishermen now facing indefinite summer closure from June to September, people are still in the dark about the chief cause of the problem.

As the pond prepared to close this summer, calls from local shellfishermen were directed at up to 200 pairs of cormorants who settled in small numbers on Sarson’s Island in the mid 1980s and bred quickly. The pond is currently set to close right around the time that the migratory bird arrives on the Island for the summer. Culling measures taken against the federally protected bird require state and federal permission.

“The cormorants are a piece of the pie,” said Mr. Ben David at a Monday meeting of Edgartown and Oak Bluffs town leaders, called to discuss a plan of action for Sengekontacket Pond. The meeting resulted in the formation of a subcommittee to help root out the scientific causes of ongoing contamination of bivalve shellfish, in the hope that summer shellfishing may one day return to the pond. “The size of that piece needs to be determined by science,” Mr. Ben David said.

“It’s wonderful to have the two towns talking about the issue,” said Edgartown selectman Arthur Smadbeck via telephone following the Monday meeting. The two-town subcommittee will be made up of selectmen and shellfish constables from both Edgartown and Oak Bluffs, as well as members of the conservation commission and others. Mr. Ben David declined to join the committee proper, but confirmed he will act as advisor over the coming months.

A timetable and scope for the committee’s work have not yet been determined.

Mr. Smadbeck is adamant that culling wildlife not be entered into lightly. “What I got out of Monday’s meeting was that it’s not as simple as killing a lot of birds. We should use the methods that are the least intrusive on nature,” he said.

Oak Bluffs shellfish constable Dave Grunden, who will form part of the subcommitttee, was encouraged by the meeting and sees the committtee proposal as a step forward. “We’ve been working with the Edgartown dredging committee services for years and it will be good to have a management in place for the pond as a whole,” he said.

But Mr. Grunden also said any solution will be long term. “There’s no way the pond will be open next summer,” he told the Gazette. “We’re looking at two, three years minimum.”

Mr. Ben David agreed. “You may never accomplish getting it open all the time. The goal might be to have it closed for shorter periods during the summer,” he said.

A recent survey of the pond conducted by Stephen H. Jones from the University of New Hampshire based on two samples taken by Oak Bluffs shellfish constable Paul Bagnall, identified some duck and cormorant fecal deposits. Strains were found of fecal-borne microbial, or E. coli bacteria. But a large percentage of the contamination remained unaccounted for in the snapshot study.

For now, the contamination problem is confined to shellfish, which are filter feeders and the canaries in the coal mine when it comes to bacteria in the water. Once pond fecal coliform bacteria exceeds safe levels, set by the state, the pond is closed to clammers. Because the site is a popular tourist destination in the summer months as well as an important site for commercial shellfishermen, the towns have much at stake in terms of finding a solution.

As part of a wider boom across the Eastern Seaboard, the first pair of cormorants arrived on Sarson’s island in 1984, displacing snowy egrets and common terns nesting on the stone piles and baskets set up by Mr. Ben David. The island had been a rare refuge from their mammalian predators — raccoons and skunks, which were both introduced to the Vineyard in the 1960s. And as the cormorants moved in, other species have scattered.

“You can’t say ‘that’s bad,’ ” Mr. Ben David said, adding: “Nature’s dynamics are complex and managing wildlife is difficult. And things change: disease comes in as a control factor, for example. A virus can cause seals to die by the thousands — that will affect the food chain. You have to be careful giving definitive answers when it comes to nature.”

He also said that when people start to talk about culling, it introduces an emotional factor into the debate. “Animal rights groups will mandate that there is a thorough scientific basis for the eradication. They will insist,” he said.

If the subcommittee eventually concludes that some sort of measures are necessary to reduce the bird population, state and federal regulators are likely to approve only the most benign action, such as egg addling.

“I can tell you right now you’re not going to get permission to go in and kill adult cormorants,” Mr. Ben David said.