With a large segment of the Maine coast affected by red tide, Gov. John Baldacci on Friday issued an emergency proclamation seeking federal assistance for those in the shellfish and related industries affected by the invasion of the tiny plankton that taint clams, mussels, oysters and other edible, filter-feeding sea creatures.

Lobsters, crabs, shrimp and other fish that do not filter seawater to obtain food remain safe to eat during the red tide outbreak.

Working in coordination with the Maine delegation in Washington, Baldacci spent Friday seeking federal disaster assistance. His declaration opens the door for federal funding to assist businesses affected by red tide.

In Washington, U.S. Sen. Susan Collins, R-Maine, met with U.S. Commerce Secretary Carlos Gutierrez to discuss how the state’s shellfish industry has reached a state of economic emergency.

New Hampshire and Massachusetts waters also have been affected by red tide levels not previously seen. The U.S. Department of Commerce announced Friday that the Massachusetts shellfish industry will receive federal assistance.

Down East, the Cobscook Bay area of the Washington County coastline was the latest area to be closed by the Maine Department of Marine Resources for clam harvesting. That occurred late Thursday.

While national news accounts in the last week have suggested that all of coastal Maine was impacted by red tide, a significant portion of flats east of the Penobscot River remain open.

Specifically, clams may be taken from much of the rest of the Washington County coastline, between Corea in Gouldsboro and the Moose River in Trescott.

Additionally, upper Frenchman Bay, upper Blue Hill Bay, Deer Isle, Vinalhaven and North Haven areas remain open, according to Marine Patrol Lt. Alan Talbot of the DMR’s Lamoine office.

Clam diggers around Cobscook Bay await the department’s next tests for evidence of red tide bloom on Monday.

DMR scientist Jay Magowan, who monitors biotoxins, will make a determination on Tuesday whether the Cobscook Bay area flats will stay closed or reopen.

“We closed the area as a precaution,” Magowan said Friday afternoon from the DMR’s Lamoine site.

“I’m not 100 percent sure those shellfish are toxic. I know I’m putting people out of work, but I am erring on the side of caution and safety.”

Many of the 100 or so clammers who make their livings on flats between Trescott, Lubec and the Canadian border last year endured 13 weeks of closures because of red tide infections.

Cobscook Bay a year ago was closed between early July and September.

Magowan recommended the latest closure around Cobscook Bay after receiving an “alarming” report late Thursday from the Cobscook Bay Resource Center.

Will Hopkins and Heidi Leighton, who monitor levels of phytoplankton there, learned that suddenly the number of cells that cause red tide had “exploded.”

“We didn’t have any toxicological data on that, but I couldn’t afford to wait,” Magowan said. “If we waited, the cells would become toxic and we couldn’t have done the closure in time.”

Magowan described Thursday’s discovery as showing “hundreds and hundreds” of cells at the monitoring stations around the bay. By contrast, the week before had revealed only one or two cells.

Magowan is unable to say how long the bloom of Alexandrium plankton will stay.

“It will go through a cycle and eventually the cells will disappear from the water,” he described. “It’s hard to say how long that will be. It could be some weeks. I hate to say that, but it almost always happens like that.

“I don’t know how far this will go, if it fades away quickly or if it rises up to the levels we had last year.”

The Cobscook Bay closures aren’t isolated, as toxin levels in some shellfish have been reported along the coast of Maine as having reached record highs already this summer. The rainy and cool weather of the last few weeks has contributed to the continuing red tide bloom.

A number of gulls and eider ducks have been dying, possibly from consuming tainted clams and mussels.

Red tide is caused by microscopic plankton that, in high enough concentrations, can cause seawater to take on a reddish tinge.

The scourge is associated with Paralytic Shellfish Poisoning (PSP) that can result from eating contaminated shellfish. But the Maine DMR is taking all steps to keep red tide-infected shellfish from leaving the flats and making it to markets.

Shellfish harvesters, dealers and the public can keep up with the latest announcements about areas that are still closed. They can call the DMR’s toll-free red tide hot line at either (800) 232-4733 or 633-9571.

The Associated Press contributed to this report.