Snakehead Fish Invade Newton Lake

A rather bizarre and invasive fish with a fierce reputation as an unwelcome guest wherever it is found is becoming a more frequent catch for fishermen in Newton Lake.

Channa argus, more commonly known as the Northern snakehead, is considered an invasive species and an “aquatic nuisance” that has found its way into rivers, ponds and wetlands along the east coast of the United States and now, in the Newton Lake system.

The Northern snakeheads, indigenous to East Asia, have few natural enemies and are highly aggressive hunters, feeding primarily on other fish. They can survive in areas with little oxygen, giving them an advantage over many other species of freshwater fish, and can actually breath atmospheric oxygen. In other words, they can survive on land for an extended period of time.

According to the New Jersey Department of Environmental Protection, the fish were first discovered six years ago in FDR Park in southern Philadelphia. They quickly made their way into the Schuylkill and Delaware rivers and have since been discovered in creeks and river systems throughout southern New Jersey.

Many believe their introduction came from intentional releases into the wild after being purchased as pets online or through live food markets.

The snakeheads are ‘here to stay’

“They’re here to stay, boys,” one boater told a group of fishermen on the Bettlewood Avenue bridge over Newton Lake.

Local biologists agree, saying snakeheads may just be another species residents will have to live with.

“The snakeheads have been in the Delaware River system for probably five, six years now. The population is so distributed up and down the river that they’re really just going to be another species that’s here to stay,” said Chris Smith, a biologist with NJDEP.

Local fishermen have taken notice of the rise of the Northern snakeheads as well. Some even believe encounters with snakeheads are a daily occurrence at Newton Lake.

“I would imagine that at least one is caught every day,” said Glenn Hudson, an Oaklyn resident who has fished in Newton Lake for more than 40 years. “They eat just about everything. I think they’ll have some implication just because of how voracious they are. They’re as common as bass now.”

So how many snakeheads are here?

NJDEP is “extremely concerned about the population growth,” and because of the complexity and size of the Delaware River, biologists have “no way of estimating the population.”

The snakeheads currently inhabit the Delaware River from Trenton to the Commodore Barry Bridge. 

“That’s about 50 miles of the Delaware River that they’re in and all of the tributary creeks of the Delaware,” Smith said. “You have hundreds of miles of river that these fish are inhabiting now, so there is absolutely no way that the population can be eradicated.”

The northern variety of snakeheads made their claim to fame in 2002 after their presence in the Potomac River, and surrounding waterways in Maryland and Virginia, made headlines.

The fish became so widespread that the federal government banned the practice of releasing exotic species into the wild. Local governments also require anglers to kill any snakehead they catch and not return it to the water.

The concern is the potential environmental impact Northern snakeheads can have on an ecosystem. As a fairly new species of highly adapted predators, the fallout from their presence is still a mystery to researchers.

“There isn’t any sound data out there right now that indicates one way or the other whether it’s going to have an impact on the population,” Smith said. “There is always that potential that it could impact another species. But we don’t know if it’s going to be five years, 10 years, 25 years down the road until we see any of those effects.”