New Brunswick

Invasive green crab population reaches record high in Shediac Bay

The population of invasive green crabs in Shediac Bay has exploded this year, says Jim Weldon, of the Shediac Bay Watershed Association.

Conservation group is keeping track of aggressive species that's known to wreak havoc on habitat

Green crab invasion in Shediac Bay

6 years ago
Duration 0:58
More green crabs are being found in Shediac Bay than ever before.

The population of green crabs in Shediac Bay has exploded this year, says Jim Weldon, of the Shediac Bay Watershed Association.

Weldon, the green crab project manager, has been monitoring numbers of the aggressive invasive species since 2013.

"This is the highest numbers we've ever seen," he said.

Weldon attributes the harsh winter of 2014 with keeping numbers at bay last year.

"The ice was thick, the crabs that were hibernating in the mud were crushed, the numbers were way down."

In June 2015, the group found one green crab. This June, 154 were caught. (Tori Weldon/CBC)
Weldon checks 10 traps once a month between May and September. Last year he found 80 green crabs in total.

But this year, he said the numbers are increasing. In May, he trapped 111 crabs, and in June, 154 green crabs were caught.

"This year we're seeing huge numbers. We've already checked a few traps today and they are already more than we had last month."

The aggressive invasive crustacean can wreak havoc on eelgrass beds that provide shelter to other aquatic life.

"They are going to go after the seed populations of mussels, oysters, quahogs and anything that is small enough that they can open."

Fishing licence exchange

Fisheries and Oceans Canada started a pilot program in 2015 that allows eel fisherman to exchange their licence for a green crab fishing licence.

After four years of monitoring green crabs in the Shediac Bay, Jim Weldon says this year's numbers are the highest they've seen. (CBC)
In the first year, one fisherman in New Brunswick took part in the program, but in 2016, no one in the province expressed interest. There were fewer fishermen in P.E.I. and the Gulf of Nova Scotia participating this year as well.

But Weldon and officials with DFO said there isn't much of a market for the crabs yet. The green crabs can be used as bait or compost and are eaten in parts of Europe and in Korea, but not here.

In Nova Scotia, Parks Canada invites tourists to lend a hand in keeping green crab numbers down. 

For $30 each, tourists get a 20-minute 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. The crabs are then killed by placing them in a freshwater tank.

Weldon said if something isn't done to control the population in New Brunswick, the numbers will most likely continue to increase.

"They produce a large number of eggs. So, if the conditions are good, which they seem to be in Shediac Bay, we're going to have a large population again next year."

Jim Weldon says the potential for the destruction of habitat is scary. (CBC)