Northern Snakehead - Channa Argus As An Invasive Species

Channa Argus As An Invasive Species

In many areas of the world, the snakehead fish is considered to be an important food fish. Due to its economic value, Channa argus has been introduced (intentionally or not) to several areas in the continental United States. In the U.S., the snakehead is a top-level predator. Introduction of Channa argus poses a substantial threat to native fish populations.

The fish first appeared in U.S. news when an alert fisherman discovered one in a Crofton, Maryland, pond in the summer of 2002. The snakehead fish was considered to be a threat to the Chesapeake Bay watershed, and wary officials took action by draining the pond in an attempt to destroy the species. The action was successful, and two adult and over 100 small fish were found and destroyed. A man admitted having released two adults, which he had purchased from a New York market, into the pond

In 2004, nineteen northern snakeheads were captured in the Potomac River, and it was later confirmed that they had become established (were breeding). They are somewhat limited to that stretch of the river and its local tributaries, upstream by the Great Falls, and downstream by the salinity of Chesapeake Bay. Tests found that they are not related to northern snakeheads found in other waters in the region, alleviating some concern of their overland migration. Northern snakehead continue to be caught in the river as of 2012.

The northern snakehead has been found in three counties of Florida, and may be established. Apparently non-established specimens have been found in Flushing Meadows-Corona Park, New York, two ponds in Philadelphia, Pennsylvania, a pond in Massachusetts, and reservoirs in California and North Carolina. In 2008, the northern snakehead was found in drainage ditches in Arkansas, as a result of a commercial fish farming accident. It is feared that recent flooding allowed the species to spread into the nearby White River, which would allow an eventual population of the fish in the Arkansas and Mississippi Rivers.

In the summer of 2008 there was a confirmed infestation of the northern snakehead in Ridgebury Lake and Catlin Creek near Ridgebury, New York. By August 2008, the New York State Department of Environmental Conservation had collected a number of the native fish, and then poisoned the waters with CFT Legumine, a liquid rotenone formulation. After the poisoning, the NYS D.E.C. had to identify, measure and additionally process the fish to adhere with Bureau of Fisheries procedures before disposal. The Treatment Plan was operated under several agents, and New York State Police were placed on stand-by in case of protests of local residents of the area.

A new concern is that this fish's spread is getting close to the Great Lakes, which it may enter and disrupt that ecosystem.

When the snakehead was found in Crofton, the piscicide Rotenone was added to the three adjacent ponds. This method of containment killed all fish present in the water body to prevent the spread of the highly invasive snakehead. The chemical breaks down rapidly, and has a half life in water of one to three days.

The snakehead was found in a pond in Burnaby, British Columbia. The province is considering imposing a ban on the import of the fish to preserve its waterways.