Invasive green crab targeted by new ecotourism campaign

Tourists usually come to Nova Scotia for the lobster, but soon they may come for the crab.

A new program launched this month by Parks Canada offers visitors the chance to help control the population of an invasive crab species. 

"Not only do they get to see it [the crab population] first-hand in the boats with us, but they can also help reduce the numbers of an invasive species that we're having issues with," said Gabrielle Beaulieu, a project manager with Parks Canada.

Green crabs arrived via ships

The troublesome species is the European green crab.

The crabs likely arrived from overseas in the bilge water of transatlantic ships. Experts say the crabs began taking a stronghold on Atlantic Canada's coastlines in the early 1990s, but may have been here since the 1800s.

Green crabs can now be found in southern Newfoundland, southern Prince Edward Island, parts of New Brunswick and all around Nova Scotia.

Rip up habitats

The problem with green crabs is their table manners. 

In their hunt for food on the sea floor, they rip up crucial eelgrass beds. Those beds shelter young halibut, lobster and other important species. 

"Clearcutting is probably the best way to describe it," Beaulieu said.

With no more eelgrass, juvenile marine creatures have no place to hide from predators and entire generations of sea life risk being wiped out.

2 million removed

Since 2010, Parks Canada staff have removed two million green crabs, as part of a project at Kejimkujik National Park's Seaside region.

"This is what we call Basin Lake," said Beaulieu, pointing to a map. "It's now a beautiful eelgrass meadow, which at the outset was just empty."

To help with the crab catching, staff are opening to program up to tourists.

Park visitors can pay $30 each for the opportunity. The excursion offers a 20 minute rocky ATV ride down to the coast, a rowboat ride out to any of the 55 buoys in a specific estuary, and a chance to haul up as many crabs as they want.

Once caught, the crabs are killed by placing them in a freshwater tank. 

A delicacy in some parts of the world

In places like Portugal and Korea, the green crab is considered a delicacy. However, since it is not an officially recognized fish stock in Canada, here the dead crabs are used as bait or compost.

If the Department of Fisheries and Oceans establishes permits for buying, selling and marketing the green crab, its population would likely drop much quicker.

Each day staff members and volunteers check and empty the traps, which can each catch dozens of crabs every 24 hours. 

When the program started, officials were finding more than 100 crabs per trap. They now find around 30 per trap and staff hope to reduce that to 15. 

Visitors to Kejimkujik National Park's seaside site can sign up throughout the summer to participate in the crab hunt.