A bucket full of fresh quahogs, edible clams. sits on the dock in Buzzard Bay, Mass.

A bucket full of fresh quahogs, edible clams. sits on the dock in Buzzard Bay, Mass.

(The Center Square) – Massachusetts’ North Shore shellfish industry has been reeling under a red tide that makes clams and oysters toxic to humans.

A population surge of microscopic plankton, red tide can occur naturally or be ignited artificially through interference such as runoff from chemical plants and lawn fertilizer. Shellfish harvested from a red tide contain a toxin called saxitoxin, one of the most potent toxins known to scientists, and can cause paralytic shellfish poisoning in humans if consumed, according to the state’s Department of Public Health.

Last month, the Massachusetts Division of Marine Fisheries began banning the collection of an array of shellfish including bivalve shellfish, mussels and clams in areas testing above toxicity thresholds.

“It’s been a month now since these areas have been closed so a lot of these people have been out of work – they haven’t been able to harvest anything while these closures have been going on, so it’s definitely been a hard time,” Paul Hagan, owner of Denarius Trading Company, a boutique oyster distributor in Boston, told The Center Square.

The red tide has been staining the seashore and disrupting business along New England’s shore since May. Many areas are starting to reopen. Gloucester, which produces much of Massachusetts’ razor and steamer clams, is still closed, according to Hagan.

“Prices for razor clams have gone through the roof,” Hagan said.

As a distributor, Hagan must go further afield to find new sources for razor and steamer clams, but suppliers know there’s a shortage and charge a premium.

“From a wholesale perspective, it’s detrimental to business,” he said.

Next to lobster meat, Hagan said steamer clams, which are often served steamed and dipped in butter, are arguably the most important protein in New England during the summer.

“That is also the clam that is shucked – so the meat is taken out of the shell and then it’s put into a plastic gallon, and those gallons are what the fish and chips places and the fry shacks use for frying clams,” he said.

The closures have had a significant impact on the local softshell clam economy, Hagan said.

“The majority of softshell steamers do come from Essex and Ipswich, and that whole three-week span when they were closed put a real strain on the local supply, especially this time of year because this is when they’re in the highest demand,” he said.

While most oysters are farmed and the operations can be moved if problems arise, these clams are wild caught so they are entirely dependent on nature to cooperate, Hagan said.

MDMF tests the water in affected areas every day to determine safety and when bans can be lifted.

In a July 8 update, MDMF observed decreasing levels of toxin in the North Shore areas. Its most recent update from July 13 announced the partial reopening of Plum Island Sound, Ipswich River and Cranes beach for softshell clams.