A northern snakehead is an exotic fish that belongs to the Channidae family and is native to China, Korea, and other countries in the Far East. This long, thin fish has invaded many other parts of the world, where it is a very unwelcome resident. It is very adaptable to different types of freshwater environments, and drastic measures have been taken to eradicate them from these areas.
This undesirable fish can grow quite up to 47 inches (1.2 m) long and can weigh as much as 15 pounds (6,8 kg). The young snakehead is brownish in color with a gold tinge, and as it ages it turns darker brown with large black patches. It has extended anal and dorsal fins along with a short tail fin. With its flattened scaly head and large mouth, the northern snakehead does indeed resemble a snake.
Snakeheads grow quickly and reach maturity at two years of age. They are very fertile, and females may lay as much as 100,000 eggs each year. In their native environment, they usually spawn in early to mid-summer. The hungry young snakeheads feed continuously on insect larvae, zooplankton, and tiny crustaceans. As they grow, they become insatiable predators, eating fish and frogs as well as birds and small mammals.
These fish are able to acclimatize themselves to a wide range of temperatures and living conditions. Unlike most other fish, the northern snakehead can survive out of water for as long as four days. When burrowed in mud, they can endure for much longer. They also have the unique characteristic of being able to travel over land by wiggling their bodies. All of these factors make the northern snakehead very hard to completely remove from areas they have invaded.
In the past, these fish were sold in pet stores and in Asian fish markets. It is assumed that they were brought to the U.S. for these purposes, but their value as a commercial fish deteriorated as their destructive nature became more apparent. The northern snakeheads began to invade the waters of the U.S. in the mid 1970s, and they have continued to infiltrate other parts of the world as well. They not only crowd out and overtake native species, but also kill them for food. The import of these troublesome fish is now banned without permission from the U.S. Fish and Wildlife Service.
Aggressive measures are being taken to kill any and all northern snakehead fish living in American waters. Several types of herbicides have been introduced to northern snakehead infested areas but this has the disadvantage of also killing native fish. Fishermen have been encouraged to catch and kill any of these invasive fish that they encounter.