Fall 2023 Children's Sneak Previews

Northern Snakehead

Common Name: Northern Snakehead Scientific Name: Channa argus Size: Up to 3 feet (length)

The northern snakehead (Channa argus) has a most unusual ability: It can breathe outside of the water, as well as within. Juveniles can also wriggle their long, narrow bodies onto land, enabling them to travel from one pond or stream to another if needed.

This aggressive fish is native to China, southern Siberia, and North Korea, where it is fished and occasionally raised for food. But it's also been introduced around the world, including most recently, the United States, where the invasive species has caused environmental problems.

The fast-growing creatures are carnivorous, eating zooplankton when they are young, but quickly progressing to insects, small amphibians, and other fish.

Physical description

These fish, whose elongated bodies earned them their name, can grow up to three feet long in introduced areas, and even larger in their native range. They have sharp, dagger-like teeth, and canine teeth on their lower jaw. Their long dorsal fin, which runs much of the length of their body, and a powerful anal fin make them speedy swimmers. The scales are golden tan to pale brown, and they have distinctive splotches along their flank.

The juveniles are adept at moving short distances on land, however when they get older and their bodies become more rounded, it becomes more difficult. During times of drought, snakeheads generally burrow into the mud; however during rainstorms, they can more easily migrate.

Air-breathing

Channa argus has a special chamber adjacent to its gills called a suprabranchial organ. This allows the animal to absorb oxygen directly from air by gulping it in through its mouth. This adaptation enables snakeheads to thrive in low-oxygen, stagnant bodies of water in a variety of settings, from swamps to muddy rivers to canals to ponds. It can survive outside of water for up to four days.

However, snakeheads can also use their gills to respire underwater, which they often do in the winter months. In summer, and in warmer conditions—which necessitates more oxygen—the fish solely breathes air though its suprabranchial organ.

The northern snakehead is not alone in this ability: Walking catfishes, lungfishes, and betta fish can all breathe air directly as well.

Reproduction and rearing young

These fish reach sexual maturity between one and three years, depending on growing conditions, and breed from April to August. They can spawn up to five times, each time laying more than a thousand orange-yellow eggs, which are buoyant. Sometimes they can lay many more, however, approaching 50,000 eggs per year. Snakeheads often make floating nests made of bits of vegetation to protect their eggs.

Parents defend their young for several weeks, and have even been known to attack people who get too close, like a Delaware boy whose hand was bit when he reached into a pond to investigate the shimmering color of a juvenile snakehead.

Invasive spread

The northern snakehead has been introduced into Central Asia, including Kazakhstan, eastern Europe, Japan, and the United States. Because they are voracious predators that quickly grow and reproduce, they have the potential to outcompete native species, making them a significant ecological threat. (Read more: Fishermen battle invasive 'frankenfish' snakeheads.)

The largest U.S. Invasive population lives in the Potomac River drainage of the Chesapeake Bay watershed. In 2002, a snakehead was first found in a pond in Maryland. Although that population was eradicated with the use of rotenone, a fish poison, more snakeheads were found in the Potomac in 2004, and they've been well established there ever since.

Snakeheads have also been found in open water in in Arkansas, Florida, Virginia, Delaware, and New York, according to the U.S. Geological Survey. In early October 2019, a fisherman caught a snakehead in Gwinnett County, Georgia, the first sighting of the fish in the state. Federal and many state laws dictates that snakeheads be killed if they are caught. Environmentalists are concerned the fish could spread to the Great Lakes, where they could wreak havoc to those sensitive ecosystems.

However, there are several efforts to eradicate them and limit their spread, including programs to fish and eat the creatures. The state of Maryland, for example, has an annual snakehead fishing derby that teaches people how to fillet the meat and gives a small award to the person who catches the biggest one. When snakeheads are found, serious measures are often taken, such as killing everything in that particular body of water, when that's deemed possible or appropriate.

Their import is also banned in the United States, they are illegal to own in many states, and shipping or moving them across state lines is illegal under the Lacey Act.

Eating the Invasive "Frankenfish" to Stop Its Spread

Scientists Discover Massive Snake Head After Mexico City Earthquake

A massive snake head has recently been unearthed in Mexico City after a powerful earthquake hit the region. The discovery certainly excited archaeologists as years of painfully long excavation were just fast-tracked.

VIEW GALLERY - 3 IMAGES

The earthquake struck the region on September 19, and according to reports, it reached 7.6 on the Richter scale. Specifically, the earthquake hit Mexico's west coast, but was big enough to be felt by residents in Mexico City, located approximately 400 miles away. The shockwaves from the earthquake caused some damage to buildings in Mexico City, in particular, a law school near the city center.

Reports indicate that beneath this law school, a team of archaeologists from Mexico's National Institute of Anthropology and History (INAH) discovered an ancient snake head that dates back 500 years - to the time of the Aztecs. The snakehead is on the large side compared to real snakes, with the relic measuring 5.9 feet long, 3.3 feet wide, 33.5 inches wide, and is estimated to weigh 2,645 pounds.

The snake head was safely removed by crane, revealing some of its incredible colors of red, blue, black, white, and ocher.

Invasive Northern Snakehead Fish Caught In Monongahela River

The Pennsylvania Fish and Boat Commission confirmed Monday that an invasive species, the northern snakehead fish, was recently caught in the Monongahela River.

It is the first confirmed snakehead fish in Southwestern Pennsylvania, according to Kris Kuhn, chief of the fisheries management division for the commission. The invasive fish has a snake-like appearance with its sleek shape and pattern of coloring. It is known to reside only in the southeastern corner of the state, according to the agency.

Native to China, Russia and South Korea, the snakehead is a predatory fish that competes with native fish for food, potentially impacting their populations. Pennsylvania law prohibits the possession, sale, purchase and transport of live snakeheads.

"The big thing is the snakehead is a predatory fish that will compete against other fish in our three rivers, including smallmouth bass, walleye and sauger," said Gary Smith, area fisheries manager of the commission's southwest region.

"It's like having another person at the table to eat, but there's only so much food," he said.

They have been called "Frankenfish" and "fishzilla" because of their rugged reputation as aggressive and voracious feeders. They are prolific breeders. Snakeheads look similar to the bowfin fish with a single dorsal fin running the length of their upper body. But snakeheads have a long anal fin that stretches from stomach to tail. They're tasty, too, according to anglers.

The first detection of snakeheads occurred in the state in 2004 in a small pond in Philadelphia near the mouth of the Schuylkill River, said Mike Parker, communications director for the commission.

The origin of snakeheads in Pennsylvania is unknown, Parker said. They were likely introduced through the pet trade or food industry. Once a popular freshwater aquarium fish, snakeheads may have been dumped into local waterways by pet owners who no longer wanted them, establishing a breeding population, Parker said.

Since snakeheads are considered good to eat, they may have been imported by individuals as a food source, with unwanted specimens being released into Pennsylvania waters, he said.

An angler caught the snakehead in Pittsburgh's Duck Hollow section of the Monongahela River last week, according to social media reports. The angler killed the fish, which anglers are supposed to do if they catch one, to make positive identification. He took a photo, stowed the fish in a freezer and reported the catch to the Fish and Boat Commission.

The fish was examined Monday at the commission's southwest regional office in Somerset, according to Smith.

The snakehead, at 28 inches long, is at least several years old, he said

The fish was likely put in the river illegally, as there are no connecting populations in the area, Kuhn said.

The Monongahela snakehead is being treated as a single fish find because there is no evidence of an established group of fish, Smith and Kuhn said.

"It's not total panic mode," Smith said. "We're not too alarmed at this point, as we don't know if they are established."

If they are or become established, it will be difficult to prevent their expansion given the size of the rivers' fisheries area, Kuhn said.

"If you come across an invasive species in a smaller pond, you can use a toxicant or mechanically remove them with nets," he said.

But that is not case with an expansive waterway like the three rivers. If the fish would become established in the three rivers, it would be a blow to the "progress in getting our native species back given our history of polluted rivers," Smith said.

The commission is asking local anglers to keep an eye out for the snakehead fish, report it to them, and to keep the dead specimen frozen for later examination. The southwest region office can be reached at 814-445-8974.

"The anglers are out there every day, and they have a better chance of coming into contact with a snakehead," Smith said.

Anglers are encouraged to learn how to identify the snakehead by visiting the Fish and Boat Commission's webpage on the northern snakehead.

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