The state says anglers or residents that come across the invader "must kill" it.
Justin Heinze, Patch Staff
|Updated Thu, Jun 12, 2025 at 1:59 pm ET
CHESTER COUNTY, PA — A dangerously invasive fish that can move across land and live for days out of water was captured recently in Chester County, prompting warnings from game officials and conservationists about the consequences of its spread.
The fish, a northern snakehead, was pulled out of the Schuylkill River near Black Rock Sanctuary in Chester County in early June.
Natives of various parts of Asia and Africa, snakeheads are distinctive among nonnative invasive species in that they can move across both water and land.
"This means they can travel between bodies of water, rapidly expanding their range," a spokesperson for Chester County Parks and Preservation said. "Voracious eaters, they aggressively compete with native fish species for food and habitat."
Snakeheads are long, torpedo-shaped fish that grow to very large sizes: up to 33 inches long, and around 20 pounds, according to the Pennsylvania Game Commission. Their diet is indiscriminate, and they feed on a variety of other freshwater fish, amphibians, some crustaceans, and small mammals they encounter in the water or during their forays on land.
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They've even been known to devour birds.
And due to their overall strength and the size of their teeth, they can eat prey up to about a third of their own substantial body size.
Anglers who catch a snakehead "must immediately kill the fish onsite" to limit its population and spread, officials said.
Pennsylvania law prohibits both the possession and sale of live snakeheads, and fishermen who catch snakeheads are urged contact that game commission to report the location and date.
Beyond simply outcompeting native fish who share the top of the aquatic food chain, snakeheads disturb the balance of the ecosystem wherever they take hold in Pennsylvania and along the eastern seaboard of the United States. They pose a significant threat to the populations of largemouth bass, in addition to imported fish like carp and stocked fish like trout.
Northern snakeheads in PA
The first appearance of the species in the United States was in California in 1997. They appeared in the mid-Atlantic in a Maryland pond in 2002. Since then, they've been confirmed in six states altogether: Maryland and California, as well as Florida, North Carolina, Massachusetts, and Pennsylvania.
They first appeared in the Keystone State when an angler pulled one from Meadow Lake in Philadelphia in 2004.
A "maze" of interconnected tributaries and tidal sloughs run to and from Meadow Lake, and environmental authorities in the state believe snakeheads to be present both elsewhere in the lower Schuylkill River and the Delaware River, in addition to the lower Susquehanna River near the Conowingo Reservoir.
Public attention and a potential solution
In an effort to raise awareness of the issue of a potentially devastating invasive species, the fish were the highlight of a 2017 U.S. Department of Interior PR effort: "Snakeheads: A Horror Story."
As part of the initiative, the National Invasive Species Council dressed up as snakeheads during a media tour.
Officials describe them as "voracious."
"They have been found in canals, ponds, lakes, and river systems in more than a dozen states," Jamie K. Reaser, the executive director of the National Invasive Species Council, said in a Department of Interior publication. "The rate of new introductions and their spread within watersheds is alarming.”
Federal officials believe that they were imported to supply the live food fish trade, and then released into the waterways to broaden the potential market. Unwanted fish may have also been dumped from aquariums.
Snakeheads are supposedly quite tasty, and one restaurant in Washington D.C., Thip Khao, has a special invasive species menu which often includes snakeheads caught in the nearby Potomac River.
"In this case, there is an opportunity to eat it to help beat it," the DOI says.
Distinction from native fish
The snakehead bears a strong similarity to two stalwart natives of Pennsylvania waters: the bowfin and the burbot.
All three are long, angular, typically brown or auburn-colored, "torpedo-shaped" fish. Bowfin can be distinguished by the lack of scales on their head, while snakeheads have a mosaic of interlocked scales that resembles the skin of a snake.
Burbots, meanwhile, have a barbel on their chin and two dorsal fins, characteristics shared by neither the bowfin or the snakehead.
To report a northern snakehead in Pennsylvania, contact the Pennsylvania Game Commission at 814-359-5163 or complete this form.
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