May 2022, ScientificAmerican.com 57rafts were not a thing in Maine. Rather farmed mussels
were grown on a single long line threaded through
buoys bobbing on the surface of open water. In many
places, this method is cheap, efficient and effective. But
not in Maine. The state is swimming with sea ducks,
including six-pound eiders that eat their weight in mus-
sels every day. The duck problem foiled Maine’s would-
be mussel farmers for decades, until Newell and a hand-
ful of other enthusiasts learned about a Spanish method
of dropping lines into the sea from an anchored raft,
which they figured could be duck-proofed with nets.
They built 35 rafts and anchored them in various water-
ways throughout the state. And “we installed nets
around the raft—60 feet deep,” Newell says.
That solved the duck problem, but they soon faced
another. The rafts were built for calmer waters, but on
Maine’s stormy coast, winds raging at 60 or 70 knots dis-
lodged mussels and destroyed the rafts.
With the help of government grants, Newell designed
and patented a submersible raft that minimized pertur-
bations when lowered 10 to 12 feet under the waves, even
in gale winds. The raft tethered to the barge at Newell’s
Pemaquid Mussel Farms is one of these remarkable con-
traptions, and it makes growing mussels in Maine far
more viable. Using rafts that floated at the surface, New-
ell says, he harvested about 150 pounds of mussels per
rope each season. “With submersibles, it’s consistently
300 to 400 pounds. That’s about 100,000 pounds of mus-
sels a year on every raft.” It’s also a far more profitable
proposition that makes growing mussels an attractive
option for former fishers.N
aylor, the staNford ecoNomist, thiNks
these shellfish could play an important role in
a healthy diet. “Bivalves are an incredibly rich
source of protein,” she says, adding that we do not need
a huge amount of it on our plates; Americans tend to
overconsume protein and underconsume vital micro-
nutrients. Bivalves contain significant quantities of
micronutrients, including minerals such as zinc, iron
and magnesium, in addition to omega-3 fatty acids.
Fast-food eateries have yet to add mussels to their
menus, but perhaps they should: a four-ounce serving
contains nearly as much protein as a McDonald’s Quar-
ter Pounder, with more iron and far fewer calories and
saturated fat, and at a lower cost. And although the
thought of mussels as fast food might sound a bit far-
fetched, given the popularity of these bivalves in France,
Belgium, Turkey, Thailand, China and other nations, is
it not possible that they would take off in the U.S., much
as sushi did in the 1960s?
For decades the U.S. fishing industry has struggled
to harvest enough wild fish to meet the growing
demand—we want cheap fish, and we want it now. The
shocking decline of Maine’s commercial wild fisheries
shows that this approach no longer serves us. Farmed
finfish is generally cheaper than wild, and many restau-
rateurs consider farmed bivalves tastier than a lot of
wild varieties. Farmed versions of all fish are generally
more widely available, regardless of the season.
It is too soon to say whether aquaculture can bolster
Maine’s fragile seafaring sector or contribute signifi-
cantly to its economy without disrupting the state’s
iconic shoreline; large finfish facilities, such as RAS, cre-
ate additional concerns about energy use and animal
well-being. But to many scientists, economists and pol-
icy makers, one thing is becoming clear: farming fish
sustainably in concert with other animals and plants
will likely be the best approach to feeding the world’s
population in the years and decades ahead.FROM OUR ARCHIVES
The Blue Food Revolution. Sarah Simpson; February 2011.
scientificamerican.com/magazine/sa