Cobscook Bay


Defined by its high tides, turbulent waters, and bold coastline, Cobscook Bay is a remarkably rich ecosystem, teeming with wildlife above and below the water. Tucked against the Canadian border in Downeast Maine, its cold, nutrient-laden waters, strong tidal currents, and extensive intertidal habitats create critical breeding and feeding grounds for marine and shoreline species.


Cobscook Bay is home to a wide variety of marine species, as well as bald eagles, migratory shorebirds and waterfowl. A shallow 40-square-mile estuary with 200 miles of rugged, rocky, convoluted shoreline, Cobscook Bay has avoided the heavy development experienced by most estuaries on the eastern seaboard, and remains a relatively intact marine system. The Bay serves as the center of Maine's multi-million-dollar finfish aquaculture industry and provides prime habitat for sea scallops, sea urchins, and soft-shelled clams.

Cobscook Bay is remarkable for its uncommon natural beauty, outstanding ecological values and rich history of human endeavor. It is a marine ecosystem of exceptional qualities, an area of cold waters and massive tides. These tides lay bare extensive mudflats where waterfowl and shorebirds feed. Inner coves remain relatively free of in winter, attracting the largest congregation of bald eagles in the northeast and a quarter of Maine's wintering black ducks. While many know of the high number of bald eagles that soar above Cobscook Bay, and of the fish that swim within its deep green waters, it has been equally famous among marine scientists for the diversity of benthic invertebrates, the creatures that live on or in the ocean bottom.


This special place has so far been spared the degradation caused by heavy development that has afflicted most eastern seaboard estuaries. It also lies at the heart of Maine's aquaculture and sea urchin industries (perhaps the fastest growing in Maine over the last decade). Meanwhile, traditional marine livelihoods (clamming, for example) have suffered dramatic declines. The challenge at Cobscook is to find ways to maintain the health of this exceptional ecosystem, while also preserving the values of the communities surrounding the Bay and enhancing their economic vitality. Here, economic opportunity and the environment have always been interdependent, even as the potential conflicts between them have been debated. Local citizens are exploring new ways for both nature and people to flourish.


Our main focus at Cobscook Bay was the gathering and dissemination of information about the marine system. We helped to secure funding for projects that meet the ecological and economic needs of the community. We often serve as a link for like-minded individuals and organizations. Some of our activities in Cobscook Bay include:

Research: In the summer of 2005, the Conservancy helped organize an effort to monitor invasive species in Cobscook Bay through a rapid assessment of marine invasives. The assessment found the Bay to be relatively unharmed by invasives compared to other bays in Northern New England. However, one very worrisome invasive species - a sea squirt - was found in the bay.

In 2004, the Conservancy coordinated the publication of a special issue of Northeastern Naturalist devoted to research made possible by a grant from A W mellon to the Nature Conservancy, conducted in Cobscook Bay (Ecosystem Modeling in Cobscook Bay, Maine: A Boreal, Macrotidal Estuary. Northeastern Naturalist. Volume 11, Special Issue 2. 2004.). The volume provides extensive information about the oceanography and ecology of the bay (available through Cobscook Bay Resource Center website)

Education and Outreach: The Conservancy supported the efforts of the Cobscook Bay Resource Center. The Resource Center helps local resource users, scientific researchers, government agencies, educators, and others to monitor and understand the Cobscook Bay ecosystem, and to use that understanding to develop and implement strategies for economic development based on the Bay's renewable resources. The Resource Center grew out of the Sustainable Cobscook Project started in 1993 by the Conservancy and Maine Community Foundation.

Conservation Lands: While the heart of the Cobscook Bay ecosystem is the marine environment, the shoreland provides critical habitat for bald eagles and a variety of waterfowl species.  Access to and protection of inner coves is important to clammers and others as well. Many of these areas are now under some form of conservation through the work of local, state and national organizations, such as Downeast Coastal Conservancy, the Maine Department of Inland Fisheries and Wildlife, Moosehorn National Wildlife Refuge, Maine Coast Heritage Trust, and The Nature Conservancy—all working to ensuring that these lands enhance the social and economic life of local communities while continuing to protect this unique, abundant and remarkable place in nature.


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