European Green Crabs (Carcinus maenas) are no longer seasonal visitors to…

June 25, 2026Gulf of Maine Coastal Lowland

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(Carcinus maenas) are no longer seasonal visitors to these waters—they are settling in. Forty sightings from Biddeford to Chebeague Island since February, with numbers surging in June, paint a picture of year-round establishment. The crabs are winning the race to reshape the Gulf of Maine, and the stakes are high for traditions rooted in these flats.

Eelgrass beds, which anchor the coastal food web and have been harvested alongside soft-shell clams for generations, are being systematically uprooted. Soft-shell clams themselves are being crowded out on digging flats that have sustained families and towns for centuries. Green crabs are now displacing a way of life. The gulf's rapid warming has tilted conditions in their favor—they thrive where native species sicken. The crabs' year-round presence means they are not passing through. They are staying.

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