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Canada’s national invasive species strategy, “An Alien Invasive Species Strategy for Canada”, defines alien species as “species of plants, animals (including fish), and micro-organisms introduced by human action outside of their natural past or present distribution”.

Invasive alien species are defined as “those harmful alien species whose introduction or spread threatens the environment, the economy, or society, including human health.

Invasive species are one of the greatest threats to the biodiversity of Ontario’s waters, wetlands and woodlands. Originating from other regions of the world, and in the absence of their natural predators or controls, invading species can have devastating effects on native species, habitats and ecosystems.

More than 185 non-indigenous species have become established in the Great Lakes basin. Invasive species, such as the zebra mussel, Sea Lamprey and Round Goby, are aggressive, extremely adaptable, and have high reproduction rates enabling them to spread. Unchecked, these invaders will outcompete native fish and wildlife and unbalance natural ecosystems.

Invasive species are able to be introduced and spread through various pathways including:

  • Shipping vessels and containers
  • Recreational and commercial boating
  • Movement and release of live bait
  • Aquarium and water garden trade
  • Live food fish trade
  • Unauthorized introductions
  • Man-made canals
  • Horticulture and gardening
  • Seed mixtures
  • Wildlife, livestock, humans and pets
  • Increased international, national and regional travel and trade
  • Firewood

Invasive species are often extremely difficult, if not impossible to remove once established in a new environment. It is important to prevent the introduction and/or spread of invasive species.

How you can help:

  • Learn how to identify invasive species that are a threat to Ontario
  • Never release live fish or baitfish from one body of water into another
  • Drain lake or river water from your boat, livewell, motor and bilge
  • Never release aquarium or watergarden pets or plants into waterways
  • Inspect and remove aquatic plants from your boat, motor, or trailer
  • Don’t move wood and use local firewood when camping
  • Stay on trails; remove mud and plant debris before you leave
  • Report new sightings – take a photo and call the Invading Species Hotline 1-800-563-7711 or report a sighting