Asian carp started populating the Mississippi River basin, causing a lot of damage along the way. There are many connections between the Mississippi basin and the Canadian watersheds, including the Great Lakes.

It seems very likely that Asian carp will invade Canada in the future, probably via the Great Lakes. Some individuals have already been captured in Canadian waters. Efforts are under way to soften the environmental impact of their arrival.

Asian carp are a group of five different fish native to eastern Asia: the grass, bighead, silver, black and largescale silver carp. Four of these species were introduced into the southern United States for use in aquaculture and pest control, but later escaped into the wild. As hardy, robust fish able survive a variety of climatic extremes - from frigid Siberia to hot and humid Vietnam - they pose a major ecological threat to North America. Some Asian carps grow to more than 50 kilograms and longer than a metre.

Asian carp have caused considerable damage in the Mississippi River basin, competing aggressively with native species for food and preying on their larvae. Predation has not reduced their numbers because their large size makes it difficult for other fish to prey on them. Asian silver carp also tend to jump out of the water and endanger recreational boaters and water skiers.