Invasive Species Council of British Columbia

Report sightings of European green crab

Fisheries and Oceans Canada (DFO) is asking the public to report any possible sightings of European green crab (Carcinus maenas). This small coastal crab is one of the world’s top ten invasive species, according to the International Union for the Conservation of Nature, due to its potential to harm marine ecosystems.  

The European green crab is an aggressive and dominant predator with a voracious appetite. Its diet includes shellfish such as clams, mussels, oysters, smaller crabs and even small fish. Unless controlled, this new aquatic invasive species will have a significant impact on the biodiversity and habitat of Canada’s coastlines. 

While European green crabs have been found along the west coast of Vancouver Island since the late 1990’s, the recent detection in Haida Gwaii has led to the call to the public to report suspected sightings.   

The European green crab reaches 10 cm in width, is green, but can be red or yellow in colour and is distinguished by five distinct spines on the outer side of each eye. The hardy species is spread in ballast water and fishing activities. 

How to report

Any suspected sightings in the Pacific region should be reported to Fisheries and Oceans Canada by email to To enable identification and follow-up, reports should include a photograph, the GPS location and date of sighting, and a note of any distinguishing features. 

Read more about the European green crab and how to identify it. 

European green crab, Jeff Adams.
Caleb Slemmons, National Ecological Observatory Network,
Caleb Slemmons, National Ecological Observatory Network,