The government is worried that if the aggressive northern snakeheads are released from home aquariums into Saskatchewan lakes and rivers, there'll be no stopping them.

There are no known cases of the fish being caught in Saskatchewan waters.

The concern is the fish will out-compete native fish —like walleye and northern pike — for food, eventually wiping them out.

What makes the toothy fish a unique threat in Saskatchewan is that it can "walk" using its fins over short distances and breathe air.

Northern snakehead are also known to carry a disease, epizootic ulcerative syndrome, that can spread to other freshwater fish species.