The Northern Snakehead By, Mark Zofcin

Biology Scientific name:Channa argus Common name: Northern snakehead Cylindrical body and large head scales give this fish its name. It has a barrel shaped body with a long spineless fin. This fish is easily mistaken for the bowfin, another species of bony fish. The dorsal fin spans the entire back half of the fish. Biology

The fish is native to the waterways of China, Russia, and Korea. The species was accidentally introduced from aquarium fish growing to large and from accidental release in the fish market(the fish tastes good) and probably being accidentally released from aquariums (pets). How it was introduced

They were first confirmed as an invasive species in July 2004 when an angler caught and preserved two northern snake heads from the seventeen acre Meadow lake in Philadelphia county. The fish were biologically proven to be northern snake heads and several more fish were found in the lake. First sightings

Where they are in Pennsylvania Stable population established in the southern Delaware river closest to Philadelphia Also found in ponds around south east Pennsylvania. First known location in Pennsylvania was in the 17-acre meadow lake in Philadelphia county. Highest populations in Pennsylvania are concentrated around Philadelphia. It is feared that the snake heads can reach the great lakes through the Delaware river and wreak havoc with the fishing industry. Where they are in Pennsylvania

How we are solving the problem The northern snakehead has no natural predators, so eradicating them will be extremely difficult if not impossible due to their extreme breeding rate and such high adaptability. There is one poison called rotenone that stream biologists have been using that is one hundred percent lethal to channa argus however it is also deadly to other species of desirable fish. Other methods of control are being researched. How we are solving the problem

Negative effects on the environment The northern snakehead is known for its voracious appetite. The young compete with young of other species for food sources such as algae and macro-invertebrates. The adults are heavy eaters with 93% of its diet being fish. These creatures both compete with native species for food and use them as food. The young also use smaller fish and eggs as food. Negative effects on the environment

The northern snakehead’s spread may have something to do with its highly adaptable biology. While the snakehead does use gills to breathe like ordinary fish, it also breathes air like a mammal or bird in order to supplement its need for oxygen. This may be due to it being adapted to warmer, dirtier waters that would not have as much oxygen as required. The fish can use its front fins to drag itself out of the water and can survive this way, allowing it access to new waterways. Any individual of the species can survive up to three days out of water. How it got so bad

These fish generally prefer slow moving muddy waterways and lakes. Temperatures can range from zero to thirty degrees Celsius. Since these fish are predators on the top of their food chain they have little to fear from other fish, however young are preyed upon by larger sunfish and pike. Although an invasive species here, the northern snakehead plays a vital role in its native ecosystem. Preferred climate

Works cited U.S. fish and wildlife service, July 2002, retrieved from, http://www.dnr.state.md.us/fisheries/snakeh eadfactsheetedited.pdf Chesapeake bay program, Jan 2016, retrieved from, http://www.chesapeakebay.net/fieldguide/cri tter/northern_snakehead Pennsylvania Fish and Boat Commission, Jan 2016, retrieved from, http://www.fish.state.pa.us/water/fish/snake head/snakehead.htm Works cited