Northern snakeheads Channa argus are predatory fish native to Asia. They were most likely introduced to New York through aquarium dumpings and both accidental and intentional releases from fish markets. It is crucial that we stop the spread of this invasive predator to protect the health of our waters, wildlife and fishing industry.
Northern snakeheads are long, thin fish with a single fin running the length of the back. They are generally brown with large, dark blotches along their sides and can grow up to three feet long. They have a somewhat flattened head and a large mouth with many teeth. Northern snakeheads are very similar to our native bowfin Amia calva.
The fast-growing creatures are carnivorous, eating zooplankton when they are young, but quickly progressing to insects, small amphibians , and other fish. These fish, whose elongated bodies earned them their name, can grow up to three feet long in introduced areas, and even larger in their native range. They have sharp, dagger-like teeth, and canine teeth on their lower jaw.
Their long dorsal fin, which runs much of the length of their body, and a powerful anal fin make them speedy swimmers. The scales are golden tan to pale brown, and they have distinctive splotches along their flank. The juveniles are adept at moving short distances on land , however when they get older and their bodies become more rounded, it becomes more difficult. During times of drought, snakeheads generally burrow into the mud; however during rainstorms, they can more easily migrate.
Channa argus has a special chamber adjacent to its gills called a suprabranchial organ. This allows the animal to absorb oxygen directly from air by gulping it in through its mouth. This adaptation enables snakeheads to thrive in low-oxygen, stagnant bodies of water in a variety of settings, from swamps to muddy rivers to canals to ponds.
It can survive outside of water for up to four days. However, snakeheads can also use their gills to respire underwater, which they often do in the winter months. In summer, and in warmer conditions—which necessitates more oxygen—the fish solely breathes air though its suprabranchial organ. The northern snakehead is not alone in this ability: Walking catfishes, lungfishes, and betta fish can all breathe air directly as well.
These fish reach sexual maturity between one and three years, depending on growing conditions, and breed from April to August.
They can spawn up to five times, each time laying more than a thousand orange-yellow eggs, which are buoyant. Snakeheads: A Horror Story. DOI photo. Yep, we're taking credit for that.
Nevertheless, the story is totally serious. USGS photo. What makes snakeheads particularly frightening? And, they have big mouths with lots of sharp teeth. All the better to eat stuff with. They eat stuff. Lots of stuff. It has tan, dark brown or black coloring with a mottled, snake-like pattern. Its long dorsal fin runs along most of its back. It has a large mouth with a protruding lower jaw and many teeth. Young snakeheads may be golden brown or pale gray, darkening as they grow older.
Snakeheads prefer to eat fish, but will also feed on frogs, crustaceans and small birds, mammals or reptiles. Snakeheads typically feed in schools and prefer to hunt their prey in areas of low light. While the northern snakehead has no natural predators in the Chesapeake Bay watershed, young snakeheads have been reported being carried away by large birds of prey, such as ospreys and eagles.
However, once they have fully matured, northern snakeheads are not prone to predation. Female snakeheads reach sexual maturity at two years old and can lay as many as 15, eggs one to five times per year. The eggs will hatch in one to two days. Larvae remain in the nest, which both parents guard. Larvae are nourished by a yolk that they absorb by the time they are less than one-third of an inch long. After that, they feed mostly on insects, small crustaceans and fish larvae.
On average, the northern snakehead lives eight years in the wild.
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