The northern snakehead fish, scientifically known as Channa argus, seems straight out of a science fiction novel, but it is a tangible reality. This aquatic predator has the ability to breathe air, allowing it to survive out of water for up to four days as long as it remains moist. Additionally, in its early stages of life, it can move across land, seeking new bodies of water.
Invasive fish threatening U.S. lands
The United States Geological Survey has documented the spread of this predatory fish, finding a population in the Saint Francis River basin in Missouri. In Spain, species of the Channa genus are listed in the Spanish Catalog of Invasive Exotic Species, highlighting the threat they pose.
The snakehead fish’s ability to breathe air sets it apart from other aquatic species. It can thrive even in environments where oxygen is scarce, such as stagnant waters or densely vegetated areas.
A surprising fact is that it can remain out of water for up to four days. This behavior is more common in young individuals, as adults, due to their morphology, move less effectively on land.
The risk of this species spreading increases if conditions are humid. Flooding or human transport of live specimens can facilitate its expansion.
The ecological threat of a voracious predator
The snakehead fish is a very efficient predator. While young, they feed on zooplankton and insect larvae. As they mature, their diet expands to include fish one-third their size, as well as crabs, reptiles, and even small birds, posing a significant risk to native species.
This species is problematic not only because of its diet. It reaches sexual maturity between two and three years, and its spawnings are massive, reaching tens of thousands of eggs. The parents protect their young for several weeks, thus increasing their survival rate.
In the United States, the presence of the snakehead fish has been monitored for years. In 2002, it was classified as harmful wildlife under the Lacey Act, prohibiting its import without permission.
Recent reports from Missouri have detected more specimens thanks to citizen collaboration. The region, connected to the Upper Mississippi system, could facilitate further expansion of the species.
The alert reaches Spain
In Spain, the risk persists if specimens are released or illegally introduced, especially through aquariums. Local regulations prohibit the possession and commercialization of Channa spp. in the natural environment.
The lesson is clear: aquarium fish should not be released into natural water bodies. An act seemingly harmless can trigger a significant environmental problem.
In the United States, authorities advise against returning the fish to the water if one is found and to report the sighting with photographs to conservation entities. In Spain, it is essential to contact environmental authorities if a specimen is found.
The snakehead fish combines dangerous characteristics, such as its ability to breathe air and its resilience, making it a persistent threat. Prevention is key to managing this invasive species.
For more information on its expansion, consult the full report at the United States Geological Survey.
