An area in the west end of Lagoon Pond has been closed by the state Division of Marine Fisheries (DMF) to shellfishing as of this morning, due to fecal coliform bacteria above acceptable levels, according to a press release issued by Danielle Ewart, the town’s shellfish constable.
Signs went up at about 4 pm Monday, Ewart told The Times. “People can still scallop, but they can’t go quahogging or get steamers,” she said. The closure comes after a water sample tested positive for fecal coliform.
In a letter to town officials dated Dec. 2, DMF wrote, “The Division has determined that portions of the West Arm of Lagoon Pond in the town of Tisbury no longer meet the NSSP (National Sanitation Safety Program) bacterial requirements for their current classifications. Therefore, the classifications of Prime Marine (V:11.6), south of Ferry Boat Island (V:11.7), and the westernmost portion of V:11.0 in the west arm of Lagoon Pond will be changed to ‘PROHIBITED’ with a status of closed to the taking of all shellfish as of sunrise on Dec. 3, 2019.”
The DMF order expands an area behind Prime Marine previously closed “conditionally” August through September annually, and extends the area to Hines Point. The change to a “prohibited” designation closes the area to shellfishing year-round.
The closure is in an area where clammers typically access the flats. Red buoys will be placed as soon as weather permits, she said, to designate the boundary line beyond which bacterial concentrations lessen to safe levels.
The order does not affect the harvest of scallops, because only the muscle of a scallop is consumed. An area is considered unsafe for shellfishing if the coliform count exceeds 31 CFU (colony-forming units) per 100 milliliters of water, according to the release. This area has exceeded those levels twice within the past 15 times sampled, causing the reclassification.
While Ewart said she can’t identify one source of contamination, she is looking at stormwater runoff as a potential culprit. “I can’t say it’s rainfall, but it’s something we want to look at more closely,” she said. “There are a lot of contributing factors.”
This is the first time that area has been closed to shellfishing. When Ewart first joined the shellfish department, the area of closures was much larger, extending to about 45 acres, she said.
Waterfowl, development, circulation, and boat activity are all possible culprits, along with stormwater runoff, she said.
The shellfish department will continue to work with water quality experts at the local, regional, and state level to try and identify the source of the problem, Ewart said.