The New York State Department of Environmental Conservation has temporarily closed Sag Harbor Cove due to biotoxins.

The presence of marine biotoxins may result in making shellfish hazardous to eat. Within the past few weeks the DEC also closed Mattituck Inlet and Creek and 2,900 acres in the Peconic Estuary’s westernmost reaches straddling Riverhead and Southampton Towns to shellfishing due to the presence of a biotoxin, a naturally occurring substance.

The Sag Harbor alert wasn’t widely released, but was sent to some private individuals with ties to the fishing industry.

The affected area includes the cove and its tributaries lying west of the northbound lanes of the Lance Corporal Jordan Haerter Veterans Memorial Bridge, which connects Sag Harbor to North Haven.

The ban on shellfishing will continue until the DEC can determine that marine biotoxin levels are no longer hazardous, according to a DEC statement.

Greenport Village Trustee Mary Bess Phillips raised the question of the possible impact the closing might have on proposed water taxi service between Sag Harbor and Greenport.

“The proposed water taxi between Sag Harbor and Greenport is a problem with this biotoxin,” she said. “With the amount of aquaculture that is in our Peconic Estuary system, we have issues.”

She called for discussion about whether the proposed water taxi service might “damage a segment of the commercial fishing industry,” although current sites being discussed docking the water taxi are outside the cove area.

Ms. Phillips and her husband, Capt. Mark Phillips, operate a fishing fleet out of Greenport and the retail Alice’s Fish Market in the village.

Bill Faulk, an aide to county Legislator Ed Romaine (R-Center Moriches), said his office has asked the DEC to provide a plan of action.

“We’re concerned about this affecting the Peconic Bay region,” Mr. Faulk said.

Mr. Romaine and Legislator Jay Schneiderman (I-Montauk) weren’t immediately available for comment.

jlane@timesreview.com