The harvesting of shellfish and carnivorous gastropods, which was temporarily banned in the towns of Riverhead and Southampton last week because biotoxins that can cause paralytic shellfish poisoning were detected in mussels, has been extended to now include the Town of Southold, state environmental officials said.
The closures, which went into effect on April 13, now cover 1,495 acres in Flanders Bay and 92 acres in Southold Town, the state Department of Environmental Conservation said.
They include all of Town and Jockey creeks, tributaries of Southold Bay, in Southold.
In the Town of Riverhead, the closure affects Meetinghouse and Terry creeks, which are tributaries of Flanders Bay.
In the Town of Southampton, the portion of Shinnecock Bay lying east of the Post Lane Bridge in Quogue and lying west of a line extending south from the southernmost point of land at Pine Neck Point in East Quogue, to the northern terminus of Triton Lane, on the barrier beach south of Pine Neck Point, is temporarily closed.
The infected mussels, tested as part of the state’s marine biotoxin monitoring program, were found to have saxitoxin. They were taken from Meetinghouse Creek and Shinnecock Bay, the DEC said.
Clams, oysters, mussels and scallops that feed by filtering gallons of water a day to capture microscopic particles of food can amass biotoxins like saxitoxin, the DEC said.
Their ability to remove excess nitrogen from the water, scientists say, is crucial in combating the pollution that powers algae blooms, sending oxygen levels plunging. Red tides that have bedeviled Long Island waters in past summers when the waters heat up also can include marine biotoxins.
Whelks, conchs, and moon sails that prey on shellfish also can accumulate enough biotoxins to sicken people if eaten.
Over the next few weeks, more shellfish will be tested, and the DEC pledged to reopen the sites as soon as it can.
“DEC will continue to monitor for the presence of biotoxins in shellfish at several monitoring locations around Long Island and implement closures as necessary,” the department said.
In May 2019, biotoxins were found in Terry and Meetinghouse creeks and in 409 acres in Northport Harbor, the DEC said. The same part of western Shinnecock under the current closure also was shut in May 2018.
Harvesters can receive updates on the closure by calling 631-444-0480. Maps of the affected areas and information about the temporary closures, marine biotoxins and paralytic shellfish poisoning can be found on the DEC website.