Wellfleet Assistant Shellfish Constable Johnny “Clam” Mankevetch checking green crab traps.
By Doreen Leggett
“I wouldn’t have you here if it wasn’t the apocalypse.”
Those words from Wellfleet’s Assistant Shellfish Constable Johnny “Clam” Mankevetch as he motored through a plate-glass calm Chipman’s Cove on a bright blue late fall day.
He was heading to half a dozen converted eel traps he had marked with plastic-bottle buoys re-purposed from the dump, now designed to catch what Mankevetch, an upbeat nature-loving guy, calls a scourge:
Green crabs.
“I don’t want to dislike an animal, but I kind of dislike them,” Mankevetch said. “You can’t dislike one of your fellow creatures generally without having some admiration for them, so I do admire their survival abilities.”
Mankevetch remembers green crabs as a kid. Their numbers kept growing, and now, to his estimation, the European invaders are taking over. They are doing serious harm to Wellfleet’s wild shellfishery and becoming a headache for oyster farmers.
The economic driver in Wellfleet is aquaculture grants, but in times past capable, motivated shellfishermen could make a decent year’s pay from the wild. Green crabs – some say one crab can eat 40 half-inch clams a day – are putting that in jeopardy.
“The wild’s the soul. I just want to preserve that at every opportunity,” he said.
Mankevetch, with support from Shellfish Constable Nancy Civetta, took it upon himself to start a pilot project.
“Chipman’s Cove is considered our premier juvenile shellfish recruitment area,” he said. “My suspicion is green crabs are so adaptable and remarkable they can eat like Vikings when it is available. My opinion is they don’t even have to sleep. They are just mouth.”
Since spring he had caught more than 8000 crabs, surprising himself. Even in October there seemed to be no slowdown in the catch rate.
On that fair day, Mankevetch was bringing up traps filled with green crabs of various sizes and some fish bones as bait, picked clean (supplied by Hatch’s Fish Market). He wasn’t prepared for the sheer volume of green crabs to the exclusion of everything else – sea perch, mummichogs, lady crabs.
Once he hauls the traps, he is not particular about where they go; if green crabs are buried in the ground at the Department of Public Works, or he drowns them in freshwater, all fine by him.
Mankevetch just wants them out of the system.
He thinks a program like on the North Shore, where harvesters are paid 40 cents a crab through a state-funded grant, would be good for Wellfleet.
That program removed 86,000 pounds of green crabs in 2023. Trappers harvested for Intershell Seafood in Gloucester, 40- to 90-pound bags, three to four times a week until November.
Mankevetch is operating on a much smaller scale, but he wants to increase the number of green crab traps to 50 or 60, maybe get shellfishermen and aquaculture grant holders involved.
He doesn’t think green crabs will be a big money maker – his suspicion is they may provide gas money – but he thinks removing them will help protect the juvenile shellfish population.
“I should have started this a long time ago,” he said.
Mankevetch also brings 500 or so green crabs to Alex Hay, Wellfleet Shellfish Company, who blends them into compost – along with lobster bodies and fish waste. Hay then takes them to a local farmer who uses them as fertilizer.
“The only challenge is (the green crabs) are alive and moving around everywhere,” said Hay. “The fertilizer is amazing, super high in nitrogen and it breaks down very quickly.”
Hay said the composting program is very small-scale and expanding would be great.
The reason he takes the time is it’s a beneficial use of what all too often ends up in the waste stream. For the Cape that means going to SEMass, a waste-to-energy incinerator in Rochester. Burning something that is mostly water isn’t the best environmental or economic choice, Hay noted.
And removing green crabs from the ecosystem makes sense.
“Anytime we can remove (predators) it is a win for us. It is definitely helping the wild clam situation,” Hay added.
Ecologists and shellfishermen have worried about the feisty green crabs for years and along with a bait market – tautog fishermen like them — there has been a concerted effort to get them on menus.
There is even a non-profit, greencrab.org, formed in 2020 to educate the public about the problem and possibilities of increasing the harvest.
Alisha Lumea, head of marketing and brand strategy at Wulf’s Fish, a major fish house in Boston, joined greencrab.org the minute it crossed her radar screen as part of an invasive species forum.
“I started reading about them and got a little obsessed,” Lumea admitted.
Being part of Wulf’s – which works with artisanal fishermen and farmers who value a premium, sustainable product – Lumea was able to bring practicality to her passion.
Wulf’s works with a North Shore shellfisherman who added green crab harvesting to his business and the company buys and sells to chefs across the region.
Although they can be a menu item, or added to seafood stew, Lumea says they are particularly handy for stocks and soups.
“They are really flavorful and have three times more fat than lobsters,” she said. “I am waiting for someone to do a green crab aioli.”
Lumea noted that mussels and squid weren’t popular a generation ago, so she is hopeful green crabs follow a similar trajectory. Wulf’s sells green crabs year-round so restaurants can have a consistent supply. In the winter, frozen crab, the rest of the year fresh.
Wulf’s also has them available on their website for home cooks.
“It is as easy to make as chicken stock,” she said.
Mankevetch is worried green crab numbers will grow as the climate changes. “We have had no killing weather,” he said, though this polar January might change that assessment.
Green crabs are particularly hardy souls anyway. Mankevetch remembers pitting oysters for the winter, placing them in a root cellar to protect animals (and gear) from ice. When he opened the pit in mid-March green crabs came scuttling out.
Their resiliency made a strong impression even as he re-read “The Road,” by Cormac McCarthy, a post-apocalyptic story about survival after most life on earth is annihilated.
“There was nothing left, but I imagined there were green crabs. So yeah, they are even affecting my enjoyment of literature,” Mankevetch said.