While Casco Bay is still a thriving ecosystem, it is changing, and more rapidly than we might expect. In some years, lobster populations appear to be moving inshore and molting earlier.
Soft-shell clams, Maine’s third largest fishery (after lobsters and elvers), face an uncertain future. As both the waters and the mudflats of Maine become more acidic, our valuable marine resources find themselves in an increasingly inhospitable environment. Friends of Casco Bay has confirmed that coastal acidification is altering the very mud in which juvenile clams, mussels, and oysters are attempting to establish a foothold.
Clammers say that green crabs are overrunning our clam flats, devouring juvenile clams, and devastating many formerly productive clam flats in Casco Bay and beyond. Green crabs from Europe invaded our coastal waters in the early 1900s. Now, a species of green crab from Scandinavia is beginning to show up in Maine waters, probably well equipped to adapt to our cold winters.
In the mid-1990s, Casco Bay had approximately 8,700 acres of eelgrass beds, the largest and densest concentration of eelgrass along the entire coast of Maine. A 2013 aerial survey of Casco Bay, initiated by Casco Bay Estuary Partnership and Maine Department of Environmental Protection, found only about 3,700 acres, a nearly 60% decline in eelgrass beds since 2001, primarily in the embayments of Maquoit and Middle bays.
What does this mean for those of us who live, work, and play around the Bay? We have a lot of work to do. Fortunately, unlike some environmental problems, there are many things each of us can do to tackle threats to the health of Casco Bay.
Learn more about our coastal future by watching these presentations from our Casco Bay Is at Risk event which took place on September 24, 2014.
- Coastal Acidification by Joseph E. Payne, Casco Baykeeper®, Friends of Casco Bay
- Eelgrass in Casco Bay: Ecology, Importance, and Threats by Dr. Hilary Neckles, Research Ecologist, US Geological Survey, Patuxent Wildlife Research Center, expertise in seagrasses
- The Recent Rise-And-Fall of Green Crab Populations in Casco Bay, and the Consequences on Soft-Shell Clam Stocks by Dr. Brian Beal, professor at University of Maine, expertise in shellfish ecology, resource management, mariculture
- Eaten Alive! Green crabs and their impacts on Casco Bay’s marine resources by Chad Coffin, clammer, resource harvester, President of Maine Clammers Association
Read the next section of the report You Can Make a Difference in the Health of Casco Bay