Photo Credit: Em Lim

Invasive Species Action Month: Make sure you aren’t spreading European green crab

European green crab is an invasive species that is already established in several locations in British Columbia, especially the west coast of Vancouver Island. 

“As we all start heading outside and spending time on the water, there are easy, good habits we can all adopt to ensure we are part of the solution, not part of the problem,” said Gail Wallin, Executive Director, Invasive Species Council of BC.  

“Whether you’re out on your paddleboard, doing some fishing, or zipping around on a motorboat, we urge you to practice Clean Drain Dry,” she said. “Wipe off your gear, ensure your boat is drained of all water, and dry off all equipment that was in the water when you leave for home. This ensures you won’t be moving anything from one body of water to another.  Instead, you’ll be preventing the spread of invasive species and protecting biodiversity.” 

European green crabs are highly invasive, according to Dr. Nick Wong, Manager Science & Research, Invasive Species Council of BC.  

They are typically found in shallow waters with lots of vegetation like salt marshes where they can reproduce twice a year, releasing up to 185,000 eggs each time. They are known to outcompete native crabs for food and habitat and could pose a serious threat to many other marine species. European green crabs are highly destructive to eelgrass beds, critical habitat for many species of marine invertebrates and fish, including Pacific herring and Pacific salmon species 

“They will likely keep spreading, as larval crabs can easily be carried on ocean currents and may also be transported in the ballast tanks of ships,” said Wong. 

You can tell a European green crab from other species by looking for this key defining characteristic: European Green crabs have five spines between the eye and the outer edge of the shell. No native crabs share this feature. 

Take Action: How to avoid spreading European green crab, whirling disease and invasive quagga and zebra mussels 

  • When removing a boat, kayak or canoe from the water, be sure to drain buckets, bilge and ballast tanks, live wells, and bait coolers thoroughly. Remove plants, animals, and mud from trailers and watercraft, with a pressure washer if possible.  
  • Wipe down water-related equipment and allow it to dry completely before placing your watercraft or equipment in another body of water.  In warm, sunny weather that may take as little as one day, but areas that are hidden from the sun may take several days. 
  • Clean, drain and dry wakeboards, skis and floating toys.  

Following Clean Drain Dry principles will help stop the spread of European green crab and other invasive species such as zebra and quagga mussels, and the parasite that causes whirling disease. 

Learn more about Clean, Drain, Dry at 

Header Photo Credit: Em Lim

Crab Photo Credit: ISCBC

Related Posts