BROOKLIN — The Department of Marine Resources announced on Saturday that all of Blue Hill Bay north of a line between Naskeag Point in Brooklin and Lopaus Point in Tremont would be closed to shellfish harvesting indefinitely because of the risk of amnesic shellfish poisoning (ASP).
On Monday night, Swans Island was added to the closure.
These additions expand the extent of the areas previously closed by the DMR and specifically ban the harvest or possession of clams, mussels, oysters and carnivorous snails (whelks) taken from Blue Hill Bay.
The closed area includes the Salt Pond in Blue Hill, Morgan Bay in Blue Hill and Surry, and Western Bay between Trenton and the northwest shore of Mount Desert Island, as well as the wider waters of Blue Hill Bay.
Several shellfish aquaculture operations are located within the newly closed area.
There are suspended rope mussel farms east of Long Island and Hardwood Island, and in the Salt Pond. The DMR also has granted aquaculture leases for relatively small-scale oyster growing operations in the Salt Pond, upper Morgan Bay and Western Bay.
Last week, the DMR ordered the recall of mussels harvested from Frenchman Bay earlier in the month. According to the department, 58,480 pounds of mussels were affected by the recall, which went into effect on Friday, Sept. 15. By Monday, Sept. 18, the department said, 57,492 pounds — about 98 percent — of the potentially dangerous mussels had been recovered and destroyed.
ASP can result from consuming shellfish containing high levels of domoic acid, a naturally occurring substance found in the algae that form the diet of most shellfish. More common in other areas but almost always present in Maine waters at some concentration, a dangerous “bloom” of the algae producing ASP in Maine waters was identified by the DMR, and shellfish harvesting closures imposed, last year.
ASP can be extremely serious. According to the Woods Hole Oceanographic Institution, acute symptoms of ASP include vomiting and diarrhea. In some of the worst cases, victims also experienced confusion, loss of memory, disorientation and even coma.