Northern SnakeHead

An Endangered Animal

The Northern Snakehead is native to China, Russia, and Korea. This is highly invasive species. It grows to be 49-50 inches and weighs 17 pounds. It has a dorsal fin and eyes above its jaw. The Snakehead lives in freshwater. In many countries it is considered to be an important food dish.

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The first report of this species in the United States came from Silverwood Lake, California in 1997 (Courtenay and Williams 2004). Two fish were captured from the St. Johns River below Lake Harney in Florida early in 2000. There were unconfirmed reports of another 3 fish nearby. A specimen was collected in Lake Michigan, Burnham Harbor in downtown Chicago, Illinois in 2004 (D. Chapman, pers. comm.). In June 2002, an established population of this species was discovered in a pond in Crofton, Maryland. This population was eradicated by state biologists using rotenone. Fish have been reported from two locations in Massachusetts; once in 2001 and again in 2004. In July 2005, they were reported in Meadow Lake in Queens, New York and persisted in 2006 (J. Pane, pers. comm.). In late May and early June 2008, three snakeheads were collected from stream in Wawayanda, New York (M. Flaherty, pers.comm.). An attempt was made to eradicate this population in 2008.

Two fish were reportedly caught by anglers in August 2002 from Lake Wylie, North Carolina. Five years later in 2007, a large adult was caught by a fisherman in South Fork Catawba River in North Carolina (J. Rash, pers. comm.). In July 2004, several individuals were captured from a pond in FDR Park in Philadelphia, Pennsylvania. The following year young snakeheads were captured in the park pond (R. Worthington-Kirsch, pers. comm.). In June 2008, a specimen was collected by the city water department from the Schuylkill River in Philadelphia (J. Perillo, pers. comm.).

Beginning in April 2004, several fish were captured from the Potomac River in Maryland and Virginia. Although it was originally thought that these fish may have originated from the Crofton pond population, genetic evidence showed that this was an unrelated introduction (Starnes et al. 2011). The Potomac River population now extends throughout the lower Potomac from Great Falls to the mouth, including some tidal portions with moderate salinity (up to 7.6 ppt; Starnes et al. 2011). Another specimen was collected in Dogue River in Fairfax County, Virginia. A fish was collected from Massey Creek and in 2005 a breeding female was found in Little Hunting Creek, a tributary of the Potomac, Virginia. Many others have been collected in 2006 and 2007 in the Potomac basin centering around Dogue and Little Hunting creeks in Virginia and from the Anacostia River in Maryland (J. Odenkirk, pers. comm.). In April 2008, the discovery of a single specimen in a ditch near Monroe, Arkansas, led to the determination that a population appears to be established (L. Holt, pers. comm.). Their first appearance in New Jersey occurred in Delaware River tributaries as early as 2009; they have been caught by fisherman from nearly a dozen streams (C. Smith, pers. comm.).

Ecology: Channa argus prefers stagnant shallow ponds, swamps and slow streams with mud or vegetated substrate, with temperatures ranging from 0 to >30°C. This species is highly piscivorous, with fishes comprising >97% of its diet (Saylor et al. 2012).

Means of Introduction: This fish is popular in the Asian food market and most introductions were likely released for this purpose. This was the case in the founding individuals of the Crofton pond population in Maryland.

Status: Channa argus is established in Virginia, Maryland, Pennsylvania, New York, and Arkansas, but is not established in California, Florida, Illinois, Massachusetts, Delaware, and North Carolina where a few individual fish have been collected. However, the northern snakehead was eradicated from the Crofton pond in Maryland where it was established. The species is well established in the Potomac River and several of its tributaries in Virginia and Maryland (Starnes et al. 2011). Although young fish were found, the status of the Philadelphia population is uncertain. Officials believe fish may have gotten into the lower Schuylkill River and Delaware River in Pennsylvania and see no practical means to eradicate them. In March 2009, the population in Little Piney Creek drainage was eradicated with the application rotenone to more 700 km of creeks, ditches, and backwaters (L. Holt, pers.comm.). The population in Catlin Creek, New York was also treated with rotenone.