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Asian Carp
Asian Carps

Eurasian Ruffe
Gymnocephalus cernuus

Carassius auratus

Northern Snakehead
Channa argus

Rainbow Smelt
Osmerus mordax

Round Goby
Neogobius melanostomus

Scardinus erythropthalmus

Sea Lamprey
Petromyzon marinus

Tench photo by Mark Malchoff, Lake Champlain Sea Grant

Tubenose Goby
Proterorhinus semilunaris

( Fish illustrations by Joe Tomelleri )

Asian Carps

Asian carps were brought from Asia to North America in the 1960s and 70s. Since then they have migrated north through U.S. waterways towards the Great lakes. Preventing Asian carps from spreading into the Great Lakes is the best way to prevent harm to Ontario’s native fish species.

Asian carps (Silver Carp, Bighead Carp, Grass Carp, Black Carp):

  • Are successful invaders that have replaced native species in areas of the Mississippi River and its tributaries.
  • Make up more than 50 per cent of the fish by weight in some parts of the Illinois River.
  • Consume up to 40 per cent of their body weight each day, this leaves little food for native fishes to eat.
  • Can grow more than 25 centimetres in their first year.
  • Typically weigh two to four kilograms, but can weigh up to 40 kilograms and reach more than a metre in length.
  • Reproduce rapidly.

Asian carps threaten our native fishes and are a safety hazard

Asian carps prefer cool to moderate water temperatures, like those found near the shores of the Great Lakes. If Asian carps become established in Ontario waters, they could potentially eat the food supply that our native fish depend on and crowd them out of their habitat. The decline of native fish species could damage sport and commercial fishing in Ontario, which brings millions of dollars a year into the province’s economy.

The term “Asian carps” includes four species: Bighead, Silver, Grass and Black Carp. Bighead Carp and Silver Carp are the species that have spread the most aggressively and can be considered one of the greatest threats to the Great Lakes.

Silver Carp are a hazard for boaters. The vibration of boat propellers can make Silver Carp jump up to three metres out of the water. Boaters and water-skiers in areas of the Mississippi and Illinois rivers have been seriously injured by jumping fish.

What Ontario is doing

Ontario is working to keep new aquatic invaders like Asian carps out of the Great Lakes. We have made it illegal in Ontario to possess live Bighead, Silver, Grass or Black Carp as well as other invasive fish species. People have been caught, convicted and received large fines for trying to import truckloads of live Asian carps into Ontario to sell at fish markets.

Enforcement of invasive species laws is the responsibility of conservation officers who work in cooperation with other agencies, such as the federal government, to stop the illegal movement of invasive species.

Ontario has partnered with the Ontario Federation of Anglers and Hunters since 1992 on programs to fight invasive species, including education, outreach and training; province-wide monitoring; and early detection.

Ontario has been working with our partners to test our state of readiness and develop an Asian Carp Response Plan. The plan will serve as a guide to taking action should a sighting of  Asian carps in the wild be confirmed.

Learn to identify Asian carps

Bighead and Silver Carp represent the most severe threat to Ontario water.


  • Typically two to four kilograms; up to 40 kilograms in weight and more than a metre in length.
  • Very large head and toothless mouth.
  • Adult fish are dark grey with dark mottling.
  • Eyes sit below the mouth.



  • Smaller than Bighead Carp.
  • Light silver in colour with a white belly.
  • Eyes sit below the mouth.



  • Large scales that appear crosshatched.
  • Eyes sit even with the mouth.



  • Closely resembles the Grass Carp.
  • Weigh up to 36 kilograms (80 pounds) and exceed 1.5 metres (5 feet) in length.
  • Large scales with dark edges appear crosshatched.
  • Eyes sit even with the mouth.

Be sure not to confuse Asian carps with Common Carp. Common Carp are originally from Asia but were introduced to Canadian waters over 100 years ago, and are commonly mistaken for Asian carps. This diagram shows the key identification features to look out for.



Always put unwanted baitfish in the garbage and empty bait bucket water on dry land. It is illegal to dump the contents of any bait container into the water or within 30 metres of any lake, pond, river or stream.How anglers can help

  • Make sure you check your bait. As an angler, you are responsible for making sure you only possess species that may legally be used as bait – even if the bait came from a bait dealer. See the Permitted Baitfish Species website.
  • Learn to identify Asian carps. Don’t confuse young Asian carps with common Ontario species.

How everyone can help

  • Don’t release any live fish into Ontario lakes or rivers.
  • Don’t import live fish into Ontario.
  • If you have any information about the illegal importing, distribution or sale of live Asian carps, report it immediately to the MNR TIPS line at 1-877-TIPS-MNR (847-7667) toll-free any time, or contact your local ministry office during regular business hours. You can also call Crime Stoppers anonymously at 1-800-222-TIPS (8477).
  • If you’ve seen an Asian carp or other invasive species in the wild please contact the toll-free Invading Species Hotline at 1-800-563-7711 or report a sighting online.

Other Resources

OFAH/OMNR Invading Species Awareness Program. (2012). Asian Carps. Retrieved from: http://www.invadingspecies.com. This factsheet may be reproduced for non-commercial purposes.

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