The United States is full of aquatic species, that magnetize intrigued anglers from all over the world to angle. Thus, not all of these species are native to American soil. With many brought here as stowaways on cargo ships or by other means of transportation. According to the World Register of Marine Species (WORMS), globally there are between 1.4-1.6 million known marine varieties. With a further 1,000-1,500 new species being discovered each year. Some of these are hybrids due to alike varieties spawning. While others are subspecies that thrived from piggybacking to a new land. That being said, here is a list of the common invasive species found in the US.


1. Asian Swamp Eel

Largely found in Georgia and Florida, the Asian swamp eels are an air-breathing species from Southeast Asia. Initially, it was introduced in Hawaii at the turn of the century as an edible fish. Having many adaptable qualities and no known predators in the US, it was able to prosper. Their diets consist of crayfish, crab, tadpoles, and shrimp. On that note, these eels do not have an appetite and will continue to eat without means. In turn, this can alter marshland inhabitants like turtles, who feed off the same prey. But, it doesn’t end there with burrowing being the Asian swamp eel’s way of concealment, this act can damage habitats. With specialized gills, it can travel over a small distance of land and survive in cold temperatures. So, how did these eels make it to the mainland?

The 1990s saw the eel’s accidental introduction into the Chattahoochee River Basin, where it traveled to area ponds with ease. Although there is no way to know for certain, it is believed it was released from a home aquarium or nearby fish farm. As you can imagine, the population began to get out of control when it was discovered in Florida in 1997. There are two main areas where these eels dwell; the Chattahoochee River and two pockets in Florida. One is in Tampa and the other is from Everglade National Park to Miami.

2. Asian Carp

person holding yellow fish during daytime

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Although, Asian carp is a broad term used to identify the variety of fish known as bighead, black, grass, and silver carp. This invasive fish was introduced in the 1970s as a tool to clean fish farms. Secondly, it was introduced as a means of maintaining weed populations in canals and filtering sewage. 

At first, this was an effective way of maintaining fish farms, until the carp escaped into the Mississippi River. Carp are prolific eaters, consuming anywhere between 20-100% of their body weight. Asian carp are also rapid breeders and carriers of the Asian tapeworm. And, as a whole, native species and marine flora weren’t able to compete against their new neighbors.

3. Lionfish


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Believe it or not, lionfish are an invasive species in the US. This district fish for its stripes, and its uniquely frilled spine, originated in Indo-Pacific waters. Now, it can be found in abundance in the Caribbean Ocean, Gulf of Mexico, and the Atlantic Ocean. It is largely speculated that the lionfish appeared in these bodies of water, with a slow introduction over 25 years. Thus, the result was an accumulation of home aquariums dumped into the ocean.

Sadly, this is another invasive species that does not have any known predators and are harmful to varieties of game fish; like grouper and snapper. The lionfish enjoys feeding on the offspring from these hatches, which is detrimental to the grouper and snapper populations. As yet, there is no known way to eliminate lionfish without taking extraordinary measures. Therefore, at this time, they are predicted to grow in numbers with no way to reduce the population.

4. Northern Pike – Alaska

green and gray spotted fish

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While northern pike are native to parts of the US; including Alaska. They are not native to the Alaskan Mountain Range, better known as south-central Alaska. Being a highly predatory freshwater species, northern pike can disrupt food chains. This couldn’t be more true than the sensitive migratory rivers found around the Kenai Peninsula. Nevertheless, the most affected species are salmon and trout hatcheries.

It is thought that pike arrived in these south-central Alaska through illegal stocking.  The introduction of these fish occurred from either the introduction of illegal eggs or the transportation of live fish. Evidence points to northern pike potentially being set here by fishermen on purpose.

5. Cichlids – Florida

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What do the Mayan cichlid, jewel cichlid, and the oscar all have in common? They’re all invasive and non-native species found in Florida. Of the three, the Mayan cichlid is the most common. Thus, anglers can act by targeting and removing this pest species from local waterways. Aside from being an aquarium staple, Mayan cichlids are surprisingly good eaters; producing white, flaky meat.

To be a part of the fight, try nabbing one of a spinner, topwater lure, or jigging live bait. Such as crickets, worms, or shrimp. Any panfish lures are effective, but these cichlids have emerged as a hefty fly-fishing target. Additionally, jewel cichlids also make for a delicious protein. Oscars, on the other hand, are opportunistic eaters with rapid growth potential. All the species of cichlid are well established in Florida and harmful to flora, with no immediate plan to eradicate them.

A Final Thought

Once an invasive species has established itself in an ecosystem, it is extremely had to rid them. Unfortunately, it is the native fish, their roe, and even marine plants that suffer the most, with the invasive species having the upper hand without a natural predator. This is why anglers need to be aware of these species and any regulations that prohibit them from releasing back into the water if caught. This is only a small glimpse of invasive species that have implanted themselves in the United States. With gobies, snakefish, zebra mussels, quagga mussels, and peacock bass all being just as destructive to the environment.