Snakeheads are often feared in the West, where populations of the aggressive fish have occasionally taken root as invasive species. After a fisherman found a Northern snakehead (Channa argus) in a pond in Maryland, in the United States, it caused a media sensation. Biologists warned that the large Asian freshwater fish could readily become established in North America, where it could wreak havoc on native ecosystems.
The voracious top-level predators can reach a length of three feet (one meter). They prey on invertebrates, frogs, and smaller fish, though they are known to attack anything moving when they are breeding.
Snakeheads can breathe air and can survive out of water for up to four days. They can survive much longer periods of drought by burrowing into the mud. Several species of the fish are native to much of Asia, where they are commonly caught and are prized for the dinner table. They are also frequently kept as aquarium fish and are noted for their aggressive behavior.