Intrusive Travellers

Introduced to a region by accident or on purpose, these plants and animals represent a major threat to biodiversity and are very hard to control.

Here are several examples of invasive alien species found in Canada. Have you seen them?

European green crab

European green crab

Found on Canada's east and west coasts since the 1950s, the European green crab causes significant damage to mollusc and crustacean populations. It also hunts the common crab, an indigenous species.

Emerald ash borer

Emerald ash borer

Detected in Quebec and Ontario in 2002, this insect has already caused the death of millions of ash trees in America. Its larvae bore tunnels under the bark, which prevent the sap from circulating, causing the death of the tree.

Leafy spurge

Leafy spurge

Found mainly in the Prairies, the leafy spurge is a ruthless enemy of biodiversity. Its roots even produce a substance that inhibits the growth of other nearby plants! In addition, its sap may irritate human skin and can poison livestock.

Common buckthorn

Common buckthorn

Originally from Europe, this large bush grows very densely, inhibiting the growth of all other plants. Even when you cut it, its branches will grow back again from the stump without a problem.

Advice on Fighting Against Invasive Alien Species

  • Don't transport firewood from one region to another; it may contain invasive insects.
  • Keep your garden in bloom with local species.
  • Clean your outdoor equipment regularly to prevent dispersal of plant seeds.
  • Be aware of the invasive species found in your region.
  • Don't bring back any fruits, vegetables, plants or animals from your trips abroad.