While Florida struggles with pet pythons released into the wild, Canada is facing a similar problem: Goldfish flushed down toilets have not only been surviving, but positively thriving in the underground sewer systems of a number of major Canadian cities.
The problem has become so severe that the western province of Alberta's government has launched a media campaign to discourage people from flushing away their golden pets.
The discarded goldfish have been found to grow as large as a dinner plate, and are multiplying at breakneck speed, notably in the cities of Lethbridge and Fort McMurray, according to provincial government sources.
Alberta Environment and Parks aquatic invasive species coordinator Kate Wilson told national broadcaster CBC that "it's quite surprise how large we're finding them and the sheer number."
In on incident 40 massive goldfish were pulled from a stormwater pond in the town of Wood Buffalo, which Wilson said was "really scary because it means they're reproducing in the wild, they are getting quite large, and surviving winters that far north."
"Approximately one third of the invasive species out there that threaten native aquatic environments are from aquariums and the ornamental trade."
The threat to native fish species is the primary reason Alberta is focused on preventing the fish from becoming part of the region's permanent ecology. The region has had previous success battling invasive rats, currently declaring itself "rat-free", thanks to a rat hotline residents can use if they spot one of the furry critters.
Goldfish (Carassius auratus) can grow up to 19 inches long, and are omnivorous predators, eating anything from plants to bugs to fish.