thumb|right|Looking west into Cobscook Bay from [[Shackford Head State Park in Eastport]]
Cobscook Bay is located in Washington County in the state of Maine. It opens into Passamaquoddy Bay, within the Bay of Fundy. Cobscook Bay is immediately south of the island city of Eastport, the main island of which (Moose Island) straddles the two bays. In the 1930s, Cobscook Bay was part of the aborted Passamaquoddy Bay Tidal Power Project (a.k.a., Quoddy Dam Project) to generate electricity from its large tidal range.
Geography
Cobscook Bay is a large bay in Washington County, Maine that opens into Passamaquoddy Bay within the Bay of Fundy through a relatively narrow opening. It is about long and 10 wide and has a long, convoluted coastline with many islands. The mouth of the bay is bracketed by the island city of Eastport, which is principally on Moose Island, and by the town of Lubec. Other townships around the bay are Perry, Pembroke, Dennysville, Edmunds, and Tresscott. There are about 7,000 people living in the nine communities in the area, many of whom are fishermen or work in fish farming, shipping or tourism. There is a scallop fishery here. The volume of freshwater entering from streams is relatively small and the nutrient rich waters support a great diversity of phytoplankton and algae. These support a biodiverse community of fish, shellfish, marine worms and other invertebrates. Many birds feed on these and the bay is an important visiting place for migrating birds and waterfowl. Cobscook Bay State Park takes up part of the shore of the bay.
History
thumb|Eastport Museum Quoddy Dam Project Exhibit|right
Communities around the bay were traditionally involved in shipbuilding, logging, farming, fishing and trading. to build a barrage to harness the power of the tides in the area was initiated. The Quoddy Dam Project was envisaged to impound the waters of Cobscook Bay and the adjoining Passamaquoddy Bay. Construction was started and some dikes were built, but a year later, the United States Congress withdrew its support and funding and the scheme was abandoned. The Quoddy Dam Model Museum at Eastport preserves a large model of the project.
The generation of electricity from the bay's tidal currents was ultimately accomplished in September 2012 by Ocean Renewable Power Company. A turbine was installed in Cobscook Bay at the boundary of Eastport and Lubec capable of generating 180 kW of electricity, and was the first North American commercial tidal energy project to supply power to the electrical grid.
Ecology
This coastal area is home to many resident birds. One of these is the bald eagle (Haliaeetus leucocephalus) and Cobscook Bay has more pairs of these rare birds per square mile than the rest of Maine. It also houses 25% of the state's black duck (Anas rubripes) population. In the fall, the bay is used by large numbers of birds migrating southwards from their summer breeding grounds. Rare species of bird to be seen here include the harlequin duck (Histrionicus histrionicus). An invertebrate of special concern is the mystery snail (Vertigo paradoxa), an air-breathing land snail.