In a scenario where invasive species pose a growing risk to American ecosystems, a strange-looking fish with amazing abilities has raised alarm: the Channa argus, known as the northern snakehead fish. Capable of breathing air and moving on land for days, this voracious predator represents a real threat to biodiversity and fishing in several states of the country.
With a length that can exceed 90 centimeters, this fish is considered by the Missouri Department of Conservation (MDC) as an “aggressive predator.” Its diet includes small fish, crustaceans, and other aquatic organisms, which, combined with its resilience and rapid reproduction, makes it a species of high ecological risk.
Since its first appearance in 2002 in Maryland, the northern snakehead fish has spread to several states, including New York, New Jersey, Pennsylvania, Arkansas, and Missouri. In the latter, it was first detected in 2019, and sightings have been increasing ever since.
Difficult-to-Eradicate Invader
The U.S. Geological Survey indicates that its introduction was likely due to accidental or intentional releases linked to the aquarium or live fish trade. This invasive species quickly adapted to new habitats, complicating containment efforts.
One of the keys to its success lies in its biology: it can survive in murky waters and with low oxygen thanks to a respiratory system that allows it to absorb atmospheric air. It is also capable of moving on land, facilitating its spread between unconnected bodies of water.
Massive Reproduction and Territorial Behavior
Another concerning factor is its impressive reproductive capacity. Females can lay up to 50,000 eggs, which hatch in just 48 hours. Additionally, both parents aggressively protect the offspring, an uncommon behavior in invasive fish that significantly increases the survival rate of the offspring.
During this stage, adults become extremely territorial and hostile towards any threat, adding an extra challenge to eradication programs.
Official Actions and Citizen’s Role
Faced with this threat, authorities have adopted a clear policy: kill any captured specimen. The MDC recommends decapitating, gutting, or bagging the live fish to prevent its survival. Although its transportation and commercialization are federally prohibited, domestic consumption is allowed and even encouraged by some states like Maryland, which praises its meat as “soft and plentiful.”
Correctly identifying the fish is also crucial. It can be confused with native species like the bowfin, but it differs by its longer anal fin and the absence of a dark spot on the tail.
The U.S. Fish and Wildlife Service urges citizens to photograph and report any sightings, specifying the exact location. While total eradication is considered unlikely, public participation has been effective in slowing its spread in some regions.
“With the public’s help, we can control existing populations and reduce their future environmental impact,” authorities stated.
What Does the Northern Snakehead Fish Look Like?
Northern snakehead fish, like the Channa argus, are characterized by their elongated body, flat head, and long continuous fins. They are freshwater fish that can breathe air and survive out of water for short periods. Additionally, they are known for their aggressive behavior and voracity, being opportunistic predators of other fish species, crustaceans, and other animals.
Main Characteristics
- Body: Long and slender, with a flat head and eyes at the front.
- Fins: Long and almost continuous along the back, with variations in color and pattern.
- Mouth: Large with a prominent lower jaw and sharp teeth.
- Respiration: Can breathe air and survive out of water for several days.
- Behavior: Aggressive predators that can eliminate other fish and attack humans who get too close.
- Habitat: Generally live in rivers, lakes, and freshwater ponds.
- Diet: Primarily feed on fish, but also on crustaceans, reptiles, mammals, and small birds.
- Size: Can reach significant sizes, with some specimens growing over a meter in length.
- Reproduction: Reproduction occurs during the monsoon season, laying hundreds of thousands of eggs.
- Migration: Their ability to breathe out of water and move on land allows them to move between bodies of water and be easily transported.
Source: Infobae.
