Scientists say the grass carp population in the Chambly Basin is probably small, but the presence of this species in any number is bad news.
Goldfish compete with native fish for food, potentially threatening an ecosystem.
A 2008 report by the Canadian Food Inspection Agency said there were at least 486 invasive alien plant species alone in Canada.
Voracious predator could be big threat to native aquatic populations
Halifax-based scuba diver Lloyd Bond says in the last three years he's seen increasing numbers of butterfly fish, seahorses, cornet fish, trigger fish, puffer fish, and many other species not native to Canadian waters.