With their thick, hard shells, oysters may appear well protected, but a lot can go wrong before they end up in markets and restaurants.
Greenhouse gas emissions blamed for global warming also are making the ocean more acidic, which can interfere with the ability of shellfish like oysters to develop their shells.
Bill Mook runs an oyster hatchery in Walpole, Maine. He heard about the problem from West Coast oyster farmers years ago.
He teamed up with researchers at the University of New Hampshire to install a monitoring system that helps him manipulate growing conditions and give his oysters a better start.
Mook is now pushing for expanding such monitoring to the rest of the Maine coast so others can better mitigate and adapt to the impacts of climate change.