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Asian Carp
Asian Carps

Eurasian Ruffe
Gymnocephalus cernua

Carassius auratus

Northern Snakehead
Channa argus

Rainbow Smelt
Osmerus mordax

Round Goby
Neogobius melanostomus

Scardinus erythropthalmus

Sea Lamprey
Petromyzon marinus

Stone Moroko
Pseudorasbora parva

Tench photo by Mark Malchoff, Lake Champlain Sea Grant

Tubenose Goby
Proterorhinus semilunaris

Wels Catfish
Silurus glanis

Sander lucioperca

( Fish illustrations by Joe Tomelleri )


Fish InvadersInvasive fish can be introduced and spread in a variety of ways including, ballast water, movement of bait, the aquarium and water garden trade, live food fish, unauthorized introductions and canals and water diversions.

Invasive fish species impact our aquatic ecosystems by competing with native fishes for food and habitat, altering food webs and preying on sport fish eggs and larvae populations.

Natural movement of species outside their natural range occurs over long periods of time; however, humans can contribute to the spread of invasive species, such as Round Goby and Eurasian Ruffe.

You can help prevent the spread of these unwanted species.

  • Learn to identify invasive fish species that are a threat to Ontario and how to prevent the spread of these unwanted species
  • Never buy or keep live invasive fish. If you have any information about the illegal importation, distribution or sale of invasive fish, report it immediately to the Ministry of Natural Resources TIPS line at 1-877-TIPS-MNR (847-7667) toll-free any time
  • Don't release any live fish into Ontario lakes, rivers or streams. Return or donate unwanted aquarium fish to a pet store or local school
  • Inspect your boat, trailer and equipment – remove all plants, animals and mud, and dispose of them on dry land or in the garbage
  • If you see an invasive fish in the wild, please contact the toll-free Invading Species Hotline at 1-800-563-7711 or report a sighting online