Snakehead fish are large, freshwater predators from the Channidae family that are native to Africa, Malaysia, Indonesia and various locations throughout Asia. These fish are plentiful in their native waters as there are some 28 varieties of snakehead fish.

The snakehead fish is very unique and different from the average fish. While they are similar, in body-type, to muscular eels, some snakehead varieties can grow to at least four feet in length. This fish got its name because of its stereotypically flat, snake-like head and toothed mouth.

What really make the snakehead so unique is its voracious appetite and its ability to breathe air. This fish is so adaptable, in fact, that it can travel short distances across land and live for short stents of time out of the water.

While there have been reports of snakeheads attacking and killing humans, they usually settle for fish, amphibians and small mammals. However, at least one species of snakehead, the Channa micropeltes, has been known to attack people when they approached the snakehead’s nest or their young.

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Over the years, these superb predators have found their way into the lakes and rivers of the United States, and this is where the problem of introducing a very adaptable, fierce predator into a new environment begins. The northern snakehead, or Channa argus, have been brought into the United States for two main reasons. There were going to be used as freshwater aquarium fish and as a specialty food.

It is reported that the northern snakeheads found in American waters are either illegally stocked in an effort to establish a local food source or aquarium owners eventually released the fish after they no longer wanted to or could care for them properly. Once introduced into their new homes, these fish tend to flourish.

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In fact, there are several species of Channidae that can tolerate a wide range of water temperatures. So, neither the warm waters of the south nor the cold waters of the north would prevent many snakeheads from becoming an established, yet undesirable, new resident.

Once established, these fish can expand their range by swimming to adjoining waterways or can even move short distances over land to nearby sources of water. The adaptability of these fish is not the only thing that makes them such a threat. The northern snakehead also breeds extremely easily.

Combine the northern snakehead’s adaptability, carnivorous appetitive, the ability to move over land and a lack of natural enemies, and you end up with a real and present threat to American waterways and the indigenous species of aquatic life that resides in these waters.

While this might not seem like a very significant environmental threat, the impact of releasing a pet snakehead or a food fish into local waters where that fish is not native is real.

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With no natural enemies in U.S. waters, the snakehead’s prolific breeding habits and hardy constitutions create a real potential for snakehead fish to multiply and destroy entire populations of fish and amphibians in the waters in which they are released. Many of these fish and amphibians are already on the endangered species list, and the snakeheads can only make things worse.

Consider this: At all stages of life, the northern snakehead competes with native fish and other aquatic wildlife for food. Native fish and wildlife populations, which already rely upon smaller fish, crustaceans, frogs, snakes, lizards and young waterfowl, will have to compete with these top-predators, and this could put them in great danger.

If snakeheads become established in a specific body of water, they can disrupt the ecosystem’s predator-prey balance. This can be catastrophic for native species.

Additionally, when a new species is introduced to an already established body of water, there is always the potential of the species bringing new diseases and parasites along with it. And, it does not appear that only large populations of snakeheads create environmental problems for American waterways. Even just one snakehead poses a threat because of its voracious feeding behavior.

In 2002, the United States Fish and Wildlife Service added snakeheads to the list of “injurious fish.” This means that snakeheads are prohibited from being imported into the United States.

Many states now even prohibit the possession of live snakeheads. However, these bans have not completely stopped illegal snakehead-activities, which have been recorded in most of the states where bans are in place. It is also reported that snakeheads can still be obtained over the internet.

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If snakeheads are found in the wild, the only means of eradicating the population would involve the complete eradication of the fishery with a piscicide, a chemical substance which is poisonous to fish. While this can be effective in small, isolated bodies of water, it does not generally work in large lakes or river systems.

This is what officials in Crofton, Maryland decided to do when northern snakeheads were discovered by anglers in 2002. This first Maryland snakehead was a long, skinny fish about 18 inches from end to end.

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Because the fisherman didn’t recognize the strange fish, he took a picture of it and put it back in the pond. Later, he gave the photo to the Maryland Department of Natural Resources (DNR). Sure enough, the fish was identified as a snakehead.

It wasn’t until another angler caught a snakehead in the same pond and netted some babies that officials really became concerned. Their concern was based on the fact that a heavy rain could possibly wash some snakeheads from the pond and into a nearby river, which runs through a National Wildlife Refuge and on to the Chesapeake Bay, the largest estuary in North America. Because of this, authorities acted quickly.

To eliminate the snakehead menace, Maryland wildlife officials dumped the piscicide rotenone into Crofton Pond. This succeeded in killing all of its fish. Six adult snakeheads and greater than 1,000 juveniles went belly-up, along with all of the pond’s native fish.. They thought the snakehead problem was solved.

Two years later, northern snakeheads reared their heads again, and this time they showed up in the Potomac River. Experts worried that snakeheads in the Potomac, by eating other fish or out-competing them for food, could drive down numbers of more desirable species, such as largemouth bass and shad.

Poison just wasn’t an option this time. You can dump poison in a little, enclosed pond, but you can’t very easily contaminate the entire Potomac in order to kill the snakeheads. It’s a wide, shallow river that originates in West Virginia and runs 380 miles before emptying into the Chesapeake Bay.

The Bay fuels the region’s economy through recreation and fishing. Snakeheads couldn’t survive in the mildly salty water of the Bay, but they could scarf down shad, fish that spawn in the Potomac and other freshwater tributaries. The complete eradication of the snakehead population would be nearly impossible.

To date, northern snakeheads have been found in U.S. waters in several states. One example was a snakehead that was hooked in North Carolina’s Paw Creek. This fish weighed 12.5 pounds and measured about 31 inches.

Because it is illegal to return a live snakehead fish to an American body of water, the fish was turned over to the Wildlife Resources Commission. However, this was not the first, and probably not the last, time a northern snakehead fish was caught in North Carolina.
Snakeheads have been caught in this area in 2002 and 2007. And, Paw Creek is an environmentally-dangerous place to have these fish because it straddles two lakes giving the injurious fish a lot of room to expand and invade.

The New York State Department of Environmental Conservation (DEC) Fisheries staff also responded to a report by a local angler of an invasive species in Catlin Creek near Ridgebury Lake in the town of Waywayanda.

The DEC recognized the danger of an infestation of northern snakehead fish. Left unchecked this predatory, invasive fish can rapidly expand its population and territory with real and negative economic impacts to the Hudson River watershed fisheries. Not to mention the fact that it can cause potentially irreversible harm to the rare and endangered species in the area.

Because of this threat, the DEC took immediate action in an attempt at containing the snakehead spread by erecting temporary fish barriers in Catlin Creek. DEC determined that swift action to eradicate this species is essential in protecting the native fish and amphibian populations and in preventing any further expansion of Northern Snakeheads beyond the headwaters of Catlin Creek.

It doesn’t appear that there is a quick fix to the Northern Snakehead problem. The key to managing snakeheads is to prevent them from becoming an established species in the first place. This may be difficult since they are already in U.S. waters and there numbers seem to be on the rise.

A tragedy of the commons is a type of social trap that involves a conflict over resources between an individual’s interests and that of the common good. In this situation, a group of people work toward short-term individual gains, which, in the end, leads to a loss for the group as a whole.
Tragedy of the commons originated from a parable published in 1833 by William Forster Lloyd. The theory itself, however, dates back to Aristotle who said:

“That which is common to the greatest number has the least care bestowed upon it.”

Aristotle knew what he was talking about and one great example of this is the overfishing of our oceans, which has been increasing dramatically over the last 50 years as advances in fishing technology have been made.

In years gone by, it was common to see trawlers and fishing boats at the many ports around the country, and world. These boats, however, have been replaced by vast fishing ships that are capable of being at sea for weeks on end. These factory ships come with all the bells and whisles needed to preserve each day’s catch, which means that these efficient ships need to return to port only when their holds are full of fish.

As is the case with many advances in technology, the birth of the factory fishing ships brought about some devasting changes to the commercial fishing industry. While there was an initial seven percent increase in the number of catches each year during the 50s and 60s, there has been a steady decline in the size of the fish in each catch.

Additionally, roughly 20 of the planet’s smaller, but once prolific fisheries have vanished over the last 25 years. Many more fisheries are having serious trouble staying afloat and may not recover from this overfishing catastrophy.

As can be expected, technology found a way around the ever-decreasing size of the fish being caught in the indiscriminate trawler nets. Smaller mesh is being used, which allows much smaller fish, and other sealife, to be trapped. Because a lot of these smallfry are just that — too small — to be used as human seafood, many are crushed or minced and, ultimately, used as fertilizer or animal food.

As mentioned, net fishing is very indiscriminate, unlike a seasoned fisherman who knows what to keep and what to return to the sea to be allowed to grow into a real keeper. Today, just about any sea-living creatures, big or small, can get trapped in these new super nets.

It has been estimated that with every ton of prawns (or shrimp) caught, roughly three tons of other fish are caught, killed and discarded. Another estimated 20,000 porpoises die every year in the Atlantic and Pacific oceans in nets intended for salmon and tens of thousands of dolphins are killed yearly by the tuna-fishing industry.

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It is necessary to mention that many types of commercially-caught fish have been harvested so feverishly around the globe that a once seemingly endless supply is now threatened on global levels. In fact, some research says there is reason to believe that the commercial fishing industry has actually prompted a change in the gene pool of several species of fish. If this is true, these fish are much less likely to thrive and may not be able to bounce back from the overfishing.

A study at Stony Brook University in New York focused on six generations of a small anchovy-like fish. Striking evolutionary changes were noted. The latter generations of fish turned out to be smaller, were less interesting in foraging for their food and produced fewer viable eggs.
Although this study was conducted in a laboratory setting, the findings could help explain an odd occurrence that has had fishermen and scientists perplexed for years. Even after overfishing has been halted, the population of many fish species simply do not bounce back to their previous numbers.

It appears that, as the larger fish are removed from the species’ gene pool, future populations get a little smaller with each passing year. The larger fish may be caught prior to mating, therefore, their stronger, healthier genes are lost leaving the smaller fish to replenish the depleted population.
The findings of the Stony Brook study challenges the assumption that if a few million fish are left in the ocean, even after overfishing has taken place, there will be enough for a given species of fish to restock itself. This assumption is further challenged by another study conducted by researchers at the University of Washington.

The researchers focused on and studied a population of New Zealand snapper, which had been depleted to around three million remaining fish. They assumed that three million would be enough to allow the population to replenish itself; however, what they found was quite different.
The scientists discovered that only one in 10,000 fish was still capable of mating. This meant that the genetic diversity of the entire snapper population depended on just a few hundred fish. Consequently, a reduction in a species’ diversity leaves the remaining population much more susceptible to environmental factors and pollutants, and it makes them less able to survive or repopulate the species.

If these studies are correct, it would seem logical that longer periods of reduced or completely-halted fishing would be required for the successful repopulation of overfished species.

Nature’s ability of restoring depleted fish populations is also dependent on whether the oceanic ecosystems are still capable of supporting an increased number of certain species of fish. Drastic alterations in the makeup of different species’ populations might possibly create new equilibrium energy flows which actually start to involve other species.

This ecosystem shift can have startling effects. For example, if virtually all the trout are eliminated from a certain area, the carp will most likely take over. If this happens, it will be impossible for the trout to re-establish a successful mating population.

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Because of global overfishing, trawlers must seek their catch in deeper waters, which is threatening the delicate deep-sea ecosystem and the much diverse marine life that calls these areas home. Look at the coelacanths, which are closely related to lungfishes. These amazing fish were believed to have been extinct since the end of the Cretaceous period. However, in 1938, a healthy, live specimen was caught off the east coast of South Africa.

What will happen to species, such as the coelacanths, if overfishing continues at the current rate?

While much factors into the problem of overfishing, one thing is sure. Ask just about any avid sea fisherman and they will confirm that the fish are smaller now than they used to be. With the whoppers being caught before they ever reach their spawning grounds, it may take many generations before the true kings-of-the-sea return. Hopefully, they will return.

With the help of such organizations as the Marine Stewardship Council (MSC), an independent organization committed to finding a solution to the overfishing crisis, maybe there is still hope.
The MSC was founded in 1997 and has developed an environmental standard for sustaining and managing today’s oceanic fisheries. They reward environmentally responsible fisheries with the use of their blue product ecolabel. Consumers concerned about overfishing are now able to purchase seafood that has been independently scrutinized against MSC’s standards.
Since this past January, 22 fisheries, nationally and internationally, have been evaluated and granted certification for meeting MSC’s environmental standards.

Today, there are roughly 500 seafood products being sold in 25 countries around the plant that meet these standards. This may seem like only a drop-in-the-bucket; however, many times environmental improvement begins as a small effort but ends up making huge, positive progress that benefits the common good.