Angry Canadian Crabs Invade Coast of Maine

A major threat to marine ecosystems, the green crab is so much more than an angry face. davemhuntphotography/Shutterstock

An army of raging Canadian crabs has stormed the shores of Maine and laid siege to local marine life.

Sound a bit dramatic?

You've never met a green crab.

This ultra-aggressive crustacean — dubbed the "cockroach of the sea" for its ability to thrive under extreme conditions — has a rap sheet as long as the Nova Scotia coastline they hail from.

Moving on from menacing the Canadian fishing industry, they're now raining hell on Maine's coastal ecosystem.

While their main target appears to be the region's soft-shell clam population, they're also munching through acres of eelgrass, a native flowering plant that shelters and nourishes life under the sea.

In fact, during a controlled study, researchers at the University of New England set green crabs loose on a meadow of eelgrass. The resulting carnage, they say, conjured images of Edward Scissorhands mowing through blades of grass.

"What we're seeing is this insane level of aggressiveness," Markus Frederich, a professor at the University of New England, told the the Associated Press.

While green crabs, an invasive species, have long established a beachhead in the United States, these Canadian counterparts seem to have serious anger issues.

Indeed, even scientists are rattled by the rage.

In an email sent to the Associated Press, University of New England researcher Louis Logan recalls the difficulties of trying to label the Canadian green crabs for the study. From five feet away, the animals were already waving their pincers at him.

"Any time I went down to grab one they went to grab me instead," he wrote, adding that one of the crabs even hurled itself from the water to get a hold of him.

An illustration of invading green crabs
No stranger to these raging crustaceans, the Newfoundland government has released an illustrated field guide entitled, 'The Green Crab Invasion.'. Newfoundland Fisheries and Land Resources

So why are green crabs so angry?

After all, they're Canadian — a nation renowned for citizens who are polite, easygoing, intelligent, funny, handsome and, of course, humble.

Maybe it has something to do with their peculiar bloodline. Canadian green crabs are a hybrid, blending genes from their crustaceous cousins in the eastern U.S. and northern Europe. They're likely relatively newcomers to Canadian waters as well, with the first green grab discovered in 2007. With few natural enemies, their population has since skyrocketed. Hardly model citizens at home, green grabs have been blamed for pillaging Newfoundland's already precarious lobster and scallop industries.

"They were born ferocious," Cynthia McKenzie, a scientist with the Department of Fisheries and Oceans, told CBC News at the time.

Indeed, the green crab menace even prompted the Newfoundland government to release an illustrated guide to spotting — and reporting — them to authorities.

And that was more than a year ago. Since then, these muscular marauders have moved on to Nova Scotia, and now they have Maine in their pincer grip.