Northern snakehead

The northern snakehead (Channa argus) is a species of snakehead fish native to temperate East Asia, in China, Russia, North Korea, and South Korea. Their natural range goes from the Amur River watershed in Siberia and Manchuria down to Hainan. It is an important food fish and one of the most cultivated in its native region, with 510,000 tonnes annual production worldwide. Due to this, the northern snakehead has been exported throughout the world and has managed to establish non-native populations in Central Asia and North America. In the United States, it is found in Pennsylvania, Virginia, West Virginia, Delaware, Maryland, North Carolina, Arkansas, Missouri, and Mississippi.

Behaviour

The northern snakehead is a freshwater fish and cannot tolerate salinity in excess of 10 parts per million. It is a facultative air breather, using a suprabranchial organ and a bifurcated ventral aorta that permit both aquatic and aeria respiration. This unusual respiratory system allows it to live outside of water for several days. As an amphibious fish, it can wriggle its way between bodies of water or survive being transported by humans. Only young members of this species (not adults) may be able to move overland for short distances using wriggling motions. The preferred habitats of this species are stagnant water with mud substrate and aquatic vegetation, or slow, murky, swampy streams; it is primarily piscivorous, but is known to eat crustaceans, other invertebrates, and amphibians.