On a glimmering May morning, Tom Briggs pilots a 45ft aluminium barge through the waters of Casco Bay for one of the final days of the annual kelp harvest. Motoring past Clapboard Island, he points to a floating wooden platform where mussels have been seeded alongside ribbons of edible seaweed.
“This is our most productive mussel site,” says Briggs, the farm manager for Bangs Island Mussels, a Portland sea farm that grows, harvests and sells hundreds of thousands of pounds of shellfish and seaweed each year. “When we come here, we get the biggest, fastest-growing mussels with the thickest shells and the best quality. To my mind, unscientifically, it’s because of the kelp.”