Zebra Mussel
Dreissena polymorpha

Report a discovery in an unlisted area

If you think you’ve seen or caught a Zebra Mussel:

  • Do not release it into the water.
  • Catch it and keep it frozen. If you can’t do that, destroy it.
  • Note the location (with GPS coordinates if possible) as well as the observation date.
  • Contact Fisheries and Oceans Canada.

Zebra Mussel is capable of heavily colonizing hard and soft surfaces, including, docks, boats, break walls and beaches. This colonization’s is also responsible for clogging intake structures in power stations and water treatment plants.

Identifying features

Similar species (native)

Quagga Mussel (Dreissena polymorpha)

The Zebra Mussel differs from the Quagga Mussel in being smaller, squarer and narrower. The Quagga Mussel has a convex ventral surface.

Where it has been found

Zebra Mussels are found throughout all the Great Lakes, Lake St. Clair and the Mississippi river watershed.

Ecological and economic impacts

Origins and mode of arrival

Native of the Black and Caspian seas region in Southeastern Europe.

The Zebra Mussel, as the Quagga Mussel, was introduced to the Laurentian Great Lakes of North America via ballast water.

Mode of dissemination

The Zebra Mussel have rapidly dispersed throughout the Great Lakes region into river systems and smaller lakes due to passive drifting at the larval stage and their ability to attach to the hulls of boats. In addition, these mussels are very prolific and can have profound effects on ecosystems by depleting the biomass of phytoplankton communities, which in turn affect the composition of other communities within the ecosystem.

Government action

Scientific research

Fisheries and Oceans Canada is studying the Zebra Mussel population to improve its understanding of how it reacts and adapts to Canadian conditions.

For further information


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