Giant snakehead exotic predatory fish found in Rock River
MADISON – The recent capture of a highly predatory exotic fish in the Rock River between Janesville and Beloit is a clear indication that Wisconsin needs more stringent regulations on the possession of live, potentially harmful exotic fish species, according to state fisheries officials.
Department of Natural Resources fisheries staff recently captured a 24-inch long giant snakehead (Channa micropeltes), also called the red snakehead, while conducting a fish survey of the river. The giant snakehead is a native of southeast Asia and a close relative of the northern snakehead (Channa argus), which gained notoriety last summer when an established population was found in a Maryland pond and subsequently eradicated by state fisheries crews to prevent its spread to neighboring waters. It was initially misidentified as a bowfin and returned to the river after the survey crew snapped a photo.
Fisheries biologists later identified the fish in the photo as a giant snakehead and a second survey of the river section where the fish was netted failed to find that fish or any other individuals.
DNR fisheries managers are developing a plan for more sampling of the Rock River between Janesville and Beloit to determine if any more snakeheads are present. Also, the river will be surveyed for any warm-water discharges that could help the species to survive over-winter.
While the giant snakehead is unlikely to survive water temperatures of a Wisconsin winter, “the size of this specimen suggests that is has been in the river for some time,” said Mike Staggs, director of the DNR Bureau of Fisheries Management and Habitat Protection. “There are warm-water power plant discharges along the Mississippi River system from here to the Gulf of Mexico where this species might actually be able to become established.”
The giant snakehead is a large aggressive freshwater fish that can grow up to 36 inches “and is not appropriate for the private aquarium trade and is best left to public aquariums,” Staggs said.
Because adult snakeheads need a large tank that can hold at least 150 gallons of water, they can quickly outgrow the average home aquarium, which could possibly result in owners getting rid of them by releasing the fish into the waters of Wisconsin.
“It is clear that Wisconsin needs to follow the lead of other Great Lakes states, including Illinois, Indiana, Michigan, Minnesota and Ohio, and ban the possession and trade of live snakehead fish,” Staggs said.
“We need to work with the governor’s office, the legislature, the Department of Agriculture, which regulates fish imports, and the aquaculture industry and affected industry to develop effective regulations controlling the possession of live snakeheads and other exotic species that could survive in Wisconsin waters,” Staggs said.
Other exotic species of concern include swamp eels, recently found in Florida and Georgia, bighead carp and silver carp, already established in Illinois and Iowa, black carp and grass carp.
Releasing aquarium fish to the wild is illegal in Wisconsin and can result in exotic species becoming established in Wisconsin waters, much to the detriment of native fish.
“The great danger of releasing tropical fish into natural waters is the threat of introducing new diseases and parasites into the wild that can harm native species,” Staggs said.
“What’s more,” he continued, “exotic species can have harmful ecological impacts on native species and communities. Once an exotic species is established, it is virtually impossible to eradicate, as Wisconsin has seen with sea lampreys, ruffe and gobies in the Great Lakes.”
The U.S. Fish and Wildlife Service has listed all snakeheads as injurious species under the Lacey Act, meaning the federal government bans importing or transporting all snakehead species between the continental U.S., the District of Columbia, Hawaii and Puerto Rico.
The federal ban doesn’t make it illegal to own or possess a snakehead where they are currently allowed, but it does bar their transfer between states or importation into a state.
“We here in Wisconsin should join the ranks of 15 states and the District of Columbia where it is illegal to possess live snakeheads,” emphasized Staggs.
FOR MORE INFORMATION CONTACT: Mike Staggs, Director, DNR Fisheries: Madison: (608) 267-0796; John Lyons, Watershed Ecologist, Monona: (608) 221-6328; or Karl Scheidegger, Rivers Management Specialist, Madison: (608) 267-9426
For information on getting a boating license check out boaterexam.com
Click Here To Return To The Previous Page