Marissa McMahan

Fisheries Division Director

Maine’s shellfish flats are very dynamic places changing with the storms and the tides. These flats are also affected by what happens in the watershed; runoff can carry excess nutrients, contaminants, or bacteria and both erosion and shoreline hardening affects the flats.

Harvesting also affects the flats, but the biggest human-caused impact on them may be climate change. The Gulf of Maine is warming faster than 99% of the rest of the world’s oceans, which has led to widespread and rapid impacts on nearshore coastal ecosystems.

Some impacts are pretty clear. Invasive green crabs, which thrive in these warming waters, have decimated clams from Maine to Massachusetts. Other impacts are less obvious. Quahogs seem to be doing better in some parts of Maine, but it’s unclear if it’s because of the natural cycles of ups and downs or if it’s because their thick shells make them less vulnerable to predators?

There is no one in a better place to observe and report on these impacts than the shellfish harvesters and municipal marine resource committee members who spend so much of their time on these flats. To support resilient and productive ecosystems and communities, we work closely with shellfish harvesters and municipal managers who are on the front lines, to understand these complex intertidal ecosystems and we conduct research, working with research partners. Earlier this month, we had the opportunity to bring these groups together virtually to share what they observe on the flats and their various efforts to survey and monitor wild shellfish populations. This meeting was structured to focus on the harvester perspective, with a panel of shellfish harvesters who kicked off the meeting by sharing where they were from and what changes they had seen over the years in the species they were harvesting. We presented a project to develop an ecological survey and other researchers described their efforts to track changes on the flats.

“One of the things that it’s important to have harvesters here today to be able to talk to people is because we’re the front line – we are the ones who get to see the most. For years we’ve complained about the green crab invasion and more. We go to local shellfish meetings and local town council meetings to address the situation, but it takes a long time for administrators to start to dig in,” said Kevin Oliver, Harvester and member of the Yarmouth Shellfish Conservation Commission.