European green crabs have been wreaking havoc on
Maine’s shellfish industry since the early
1930s. Remarkably, in an era when
Maine fishermen sell anything
from sea urchins to worms, no market has been
developed for the invasive pests.
grow quickly. They have an especially
broad habitat, temperature and salinity
tolerance that allows for a broad
geographic distribution. All of this
makes for a great invasive species, and
nothing has evolved to handle them.”
Prof. Brian Beal
WASHINGTON DepT. of Fish & Wildlife
Because of their
small size (a large green crab would measure
fewer than three inches across), picking green
crab meat (just as delicious as rock or Jonah
crab) is a tedious and prohibitively expensive
process, a fact that has limited any commercial
harvest. Without natural predators or a fishery
to control their numbers, green crabs will
continue to out-compete native species and take
a serious toll on shellfish populations.
and a commercial green crab fishery are the only
things that we can hope for,” said Brian Beal,
professor of marine biology at the University of
arrival in the ballast water of trans-Atlantic
ships, the invasive green crabs have pushed
native species to deeper waters and are now the
dominant predator in Maine’s inter-tidal zone.
Native to the
British Isles, green crabs were first spotted on
American shores in the Long Island Sound around
1800. Since then, the voracious feeders have
been feasting their way north along the coast,
decimating populations of clams, scallops and
Beal, the green crab is a “very feisty
quickly and reproduce quickly,” he said. “They
have an especially broad habitat, temperature
and salinity tolerance that allows for a broad
geographic distribution. All of this makes for a
great invasive species, and nothing has evolved
to handle them.”
Working with the
Beals Island Regional Shellfish Hatchery, marine
biologist Bill Walton received a $10,000 grant
from the Maine Technology Institute to study the
feasibility of a commercial fishery for the
green crab. The hope was to develop a fishery
similar to what exists in the Chesapeake Bay
with soft-shelled blue crabs. The trick would be
to discover a way to catch the crabs during the
three-day period when they shed their shell and
grow a new, larger shell.
months, the project petered out. The frequency
of the molting was not as high as Walton had
predicted and when the money ran out, he was
still unable to come up with any marker to make
predictions about the time of the molt.
Beal thinks that
figuring out the molting cycles would be “worth
“I think it’s a
great opportunity and someone should take
another crack at it,” he said.
“We could get
green crabs the heck out of Maine. They don’t
belong here. History has shown that once a
species becomes a fishery, it’s destined to
doom. It would be great to create markets for
private investors as the best hope for
commercial viability studies on green crabs.
“It will take
someone with a business plan,” he said. “With
time and sampling and detailed observations,
experiments in a controlled setting —
manipulating water, food and light we may be
able to figure out the molting.”
an associate professor of food scientist at the
Maine, has been experimenting
with products that could create the need for a
commercial green crab fishery.
“The only real
reason for a green crab fishery is to get rid of
this terribly invasive species,” Skonberg said.
“We have to find a way to make the crabs
marketable. They destroy oyster beds and mussell
beds. Lobstermen get them in their traps and
those guys just crush them, they hate them so
been experimenting with what she calls a “crab
mince.” The whole crabs are put through a
deboning machine and ground down to a
crab-flavored puree high in protein and calcium.
The mince is used as an extender, a thickener or
flavoring agent in stuffed pastas, crab cakes,
stuffing and soups.
speaking, it’s a great product, but texturally,
it’s not that appealing,” said Skonberg.
also has been working on a high-protein low-fat
corn puff using the crab mince.
wanted to make a seafood flavored snack but most
of the crab flavor was volatized by the high
heat,” said Skonberg. “We ended up using cheddar
cheese and sour cream and onion flavors.”
The market for
crab mince is very limited, according to Scott
Wuerthner, sales manager at Portland Shellfish.
His company makes a mince similar to Skonberg’s
with the shells and scraps of Jonah and rock
crabs, already picked for lump crabmeat.
“We can sell it
for $1.50-$2 a pound, but it’s just not in great
demand,” said Wuerthner. “It’s got great flavor,
the raw flavor of the animal, but the uses are
limited, so a lot ends up in the freezer.”
fishermen call every day wondering if there’s a
market for green crabs.
“We tell them we
don’t want any green crab,” said Wuerthner.
“We’re pushed to sell the rock and Jonah, so why
would we throw green into the mix, especially
when the main reason we sell the mince in the
first place is to reduce our waste.”
Don Smith, 72, a
lobster dealer at the Prospect Harbor Trading
Co., has been buying and selling lobster for
nearly 40 years.
“These days, the
fishermen are really complaining about green
crabs,” Smith said. “Instead of traps full of
lobster, they’ll sometimes have whole traps full
of green crabs. They’ll just have to turn the
trap upside down and dump the thing into the
“It used to be
the same with urchins ’til they fished those