Invasive to Plate: Maine’s Green Crab Revolution

Off the coast of Maine, an ecological battle is underway. Green crabs have lived in Maine waters for over a century, but the species is actually invasive, having been brought to New England waters from Europe in the 1800s. 

While cold winters used to keep the nonnative species in check, their population has continued to grow as ocean temperatures in the Gulf of Maine have risen. The crustacean population has burgeoned into a formidable force, disrupting delicate marine ecosystems and threatening local shellfish fisheries. 

A Crustacean Conundrum

In a state famous for its lobsters, one fisherman is on a mission to expand the state’s seafood menu. With their insatiable appetites and remarkable adaptability, the European green crab population has become a scourge on Maine's coast, outcompeting native species and wreaking havoc on fragile ecosystems. The crustaceans have ravaged local estuaries—worsening erosion by digging away at marsh banks and eelgrass beds for shellfish like clams, mussels and oysters.

Both conservationists and commercial fishermen dislike the invasive crustaceans—but that’s precisely why Mike Masi wants to develop a fishery for them. Although the green crabs are damaging Maine’s shellfish industry, harvesters like Masi are trying to figure out if the crabs themselves could become a commercially viable species. If the species is going to be so abundant, it may as well become a resource.

“I predict that there will be many small-scale operations like ours throughout New England and soft-shell green crab will become a seasonal delicacy.” says Masi.

A high school science teacher turned entrepreneur, Masi is at the forefront of a pioneering effort to transform these invasive creatures into a sustainable food source. He’d long used green crabs as a teaching tool for his marine science classes at York High School—demonstrating how fishing the invasive crabs could be a valuable technique for citizen scientists to conduct population surveys. When he met Dr. Gabriela Bradt, a New Hampshire Sea Grant researcher who was investigating the viability of a soft-shell green crab market, an idea began to form.

Masi now runs Southern Maine Sustainable Shellfish with Sam Sewall, a former student and now fourth-generation York Harbor lobsterman. The two have launched their business to develop a commercial fishery for the green crabs, eventually aiming to sourcing both hardshell and soft-shell green crabs to Maine’s many seafood eateries.

“The green crab fishery has the potential to grow significantly over the coming years and we hope to be the company encouraging that growth.”

Cracking The Market: Creating Demand For Green Crabs

Despite the hearty abundance of these pesky shelled foragers, the number of buyers they’ve found is less so. Currently, Masi sells soft-shell crabs to about half a dozen restaurants. Finding takers for hard-shell crabs, the majority of his catch, has proven more difficult—the most consistent buyer he’s found is a bait supplier in Rhode Island, who uses the hard-shell green crabs to catch species like conch and tautog in Southern New England. 

When people order soft-shell green crabs, they’re supporting local fisheries and the environment, keeping a harmful invasive species in check all while getting a delicious meal. The green soft-shell crabs are just as delicious as their other soft-shell counterparts, but establishing the fishery on a commercial scale has proven to be the real challenge. 

“Markets for the hardshell crabs must be further developed. At present, the largest market for hardshells is the bait market where green crabs are used to catch species like Channel Whelks and Tautog, both of which are commonly fished in southern New England.”

Masi has, however, found markets in unexpected places—a local Buddhist temple distributed green crabs by the bagful at a Cambodian new year celebration—not as bait, but food. While the European green crabs aren’t quite the same variety available in Southeast Asia, the green crab proved to be a perfect substitution when fermented with chilis and garlic, and was a hit amongst Maine’s Khmer Cambodian community.

Green Crabs: From Trap To Table

“We currently sell directly to seven restaurants in New Hampshire and Massachusetts. We reached out directly to chefs/restaurants based on the reputation of the restaurant and their commitment to sourcing sustainable seafood. We’ve now gathered enough media attention that restaurants and wholesalers are reaching out to us.”

Green crabs are edible, although they are most often used to make soups and broths—they are smaller than most popular eating crab species like Dungeness, Rock and Jonah crabs, so there is not much meat yield per crab. 

Although they’re a recent addition to U.S. menus, green crabs have long been a delicacy in Europe, particularly Italy. But as more chefs have begun experimenting with them, the benefits of serving them up are numerous. Not only are the crustaceans tasty and sustainably harvested, they’re also economical. Creating a market for green crab eaters has become a family affair. Fisherman Sewall’s uncle, Jeremy Sewall, has made a name for himself by plating up green crabs at his nearby restaurant, fried whole and served with spiced aioli and pickled vegetables on a brioche bun.

This isn’t the only way the crabs can be prepared—New Hampshire Sea Grant has partnered with environmental educator Manomet to create a guide to catching them yourself, as well as offering an entire cookbook of ways to eat your catch, from a fresh green crab and monkfish ceviche to rangoons, risotto, and ramen.