BRUNSWICK, Maine — Chris Green, 50, has dug clams on Middle Bay’s intertidal mudflats for a long time.
“All my life. I started with my father,” Green said Tuesday, sitting in his boat, wearing thigh-high rubber boots splattered with salty muck.
In those years, he’s seen a lot of changes.
“The biggest change would be dwindling access,” Green said. “Number two is the warming water.”
Rising water temperatures have meant more clams and longer digging seasons. But they have also brought more clam predators like green crabs and milky ribbon worms.
“It’s a double-edged sword,” Green said.
Tracking those kinds of long-term changes on Middle Bay — and the rest of greater Casco Bay’s intertidal areas — is the focus of a new online information portal launched by the Greater Portland Council of Governments and the Casco Bay Regional Shellfish Working Group.
The website combines multiple data streams from several diverse information sources into a single, searchable portal designed to support planning and management in the region. It will also assist communities along the bay in exchanging information, fostering more nuanced understandings of Casco Bay’s complex, interwoven intertidal and near-shore ecosystem.
The public is invited to attend a webinar from 3:30-5 p.m. on Wednesday to learn how to use the data portal and apply it in addressing real-world challenges.
The site’s various mapping applications focus on specific themes, including shellfishing, sea-level rise, water quality and a septic system data collection.
One clickable map shows overlapping uses along the shore, from Biddeford to Boothbay Harbor. Another map tracks infrastructures sensitive to sea-level rise. A separate map is aimed squarely at the shellfishing community, tracking landing numbers, areas closed to digging, and important contact information for local officials.
“The intertidal zone plays an economically, ecologically and culturally important role in the Casco Bay region,” said Sara Mills-Knapp, director of sustainability at the Council of Governments. “Communities need to understand the intertidal zone to plan for the impacts of climate change, balance uses and manage natural resources.”
Intertidal zones are where the sea and land meet. Often muddy, they are covered with ocean water at high tide and exposed to the air and sun at low tide.
Casco Bay’s intertidal zone supports human industries such as shellfishing and aquaculture.
Last year, Freeport, Brunswick, Harpswell and Phippsburg diggers landed almost 1.3 million pounds of soft shell clams on the eastern end of Casco Bay.
The intertidal zone also includes the bay’s sandy beaches, where tourists love to flock. Twelve million people visited Maine in 2020, and 17 percent of them went to a beach, according to the Maine Office of Tourism.
Casco Bay’s intertidal zone is also home to a variety of important plant and animal species. Its eelgrass and salt marshes help stabilize shorelines, acting as a protective buffer against storm surge and flooding. This feature will only become more important as the sea level rises and more dynamic storm and flood events occur.
Middle Bay, where Green harvests his clams, is one of the few places in Maine where horseshoe crabs congregate to breed.
The organizations behind the new website are hoping the portal will be useful for those involved in planning, decision-making and climate change adaptation in Casco Bay’s intertidal zone. This includes local governments around Casco Bay, municipal committee members, other coastal stakeholders — and shellfishermen like Green.
“I’ll definitely be using it,” Green said.