Two decades ago, a walk through Freeport’s mud flats would’ve resulted in a haul of soft shell clams, each footstep making contact with a number of mollusks submerged in the mud. The screech of seabirds would have punctuated the steady rustle of the tide ebbing through the flat’s eelgrass, Maine’s common shoreline plant that is so integral for the survival of juvenile marine organisms.
Today, a visit to Freeport’s mud flats is widely different. Clammers are no longer able to depend on this formerly-abundant acreage for a reliable harvest, and rarely do you come across a clam in these waters that has reached maturity. Clumps of eelgrass skim the tide’s surface, their roots no longer home to adult mollusks. In a moment of stillness you can hear a faint chittering, a somewhat haunting sound resembling long nails typing on a keyboard.
This sound can be attributed to the European green crab, an invasive crustacean predating on some of our state’s most environmentally, culturally, and economically vital species. The desolate nature of these flats is reflective of the success of this crab in making itself at home throughout Maine’s coast, killing bivalves, eating through eelgrass beds, and eroding creek beds through excessive burrowing. Over the past thirty years, Maine’s soft-shell clams have ranked 2nd or 3rd in commercial value of all marine species harvested in Maine waters, with dockside revenues from clamming in Freeport representing 10% of revenues in 2012. Since then, this coastal town has seen a near 70% decline in landings and 50% decline in revenues to clammers.
With softshell clam populations plummeting, researchers worry that lobster may be the green crab’s next victim. Multiple studies have proven that lobsters are less likely to enter traps with green crabs around, and that the latter outcompete juvenile lobsters for food, decreasing the likelihood that Maine’s lobsters reach adulthood. Lobsters and clams account for a huge portion of Maine’s economy, so what can we do to stop this voracious crab from depleting ecosystems that are integral to the livelihoods of Maine’s human and non-human inhabitants?
Despite being one of the world’s worst invasive predators, green crabs are considered a culinary delicacy across much of their native range. In Spain they’re consumed in soups and sauces, while in Italy they’re eaten softshell and for their roe. What’s stopping them from being considered a culinary delicacy across their non-native range? A growing number of researchers, chefs, and fishers alike are having similar thoughts about transforming the green crab into a menu staple. Culinary and bait markets would support the continuous harvest of these crabs, keeping their population in check without devoting resources to futile eradication efforts. Creating a green crab fishery would make use of a highly abundant, underutilized resource, in addition to diversifying Maine’s assets in the face of a rapidly changing ecosystem thanks to climate change.
Local chefs are receptive to researcher’s suggestions of turning this crab into a delicacy. There is a gap in the market for common sea products produced using crustaceans, such as fish sauce. When asked whether they would use green crabs in lieu of a traditional fish sauce, one chef responded affirmatively, explaining that “having a local Maine product that also helps with an invasive species would be a dream!” Some restaurants are already advertising green crabs on their menus, such as Row 34 in Portsmouth. Ryan Boyd, the restaurant’s culinary director, has been buying them whenever possible from green crab fishers, serving them in the form of a soft-shell crab slider with hoisin aioli and pickled daikon.
According to green crab fisher Mike Masi, you can catch 30 to 40 pounds of crab in a trap on a one- to two- night set. The ease of fishing so many crabs means a consistent haul to bring to market, which bodes well for the success of a fishery. Creating a steady demand for green crabs would aid in countering its high reproductive rate, keeping the green crab’s population in check such that Maine waters can return to historic equilibriums. “If we fish them down, we give these natives a fighting chance,” Masi says in a 2023 interview.
Green crabs have called the U.S. home since the 1800s, when merchant ships first transported them to Cape Cod from Europe via ballast water. While they have been here longer than Maine has been called “Vacationland”, we have only recently experienced their violent effects on ecosystems. For most of their American existence, the harsh Maine winters have deterred them and prevented them from establishing themselves further north. However, climate change is here, and the gulf of Maine is warming faster than 97% of the world’s oceans, dramatically altering the range of the native species who call Maine home. The warmer waters allow the green crab to thrive, cutting short the winters that would otherwise keep their population in check. Lobster populations are increasing at the cooler, northern edge of their range, and declining at the warmer, southern edge of their range. Once abundant in our gulf, the Atlantic cod has started to move farther north and to deeper offshore waters in search of cooler temperatures. Due to its unique marine geography, Maine’s gulf is warming at faster rates than much of the world, meaning that we are going to have to pioneer climate adaptation strategies. As warming ocean temperatures threaten Maine’s most valuable fisheries and increase the volatility of marine populations, Mainers have to be able to adapt each season depending on what’s available. Integrating the green crab into Maine’s food system is the first step of many in supporting Maine’s human and non-human inhabitants in the wake of climate change.
I envision a walk in 2033 that displays a scene of rehabilitation. Freeport’s clammers are once again raking barrels of soft shell clams out of the mudflats, joined by crabbers hauling a poundage of green crabs. Last year’s juvenile lobsters are safely on their way to maturity, and the abundant eelgrass beds welcome the tide as it brings young fish to its grove. The offputting chittering once dominating Maine’s shoreline is now a memory, the loss of it a testament to the resilience – and culinary innovation- that describes the people of Maine.
