In the United States you may have heard talk about various invasive species in our waterways. Some of which are mussels such as the zebra mussels, others are crustaceous or baitfish, but one of the common names you may hear public officials talk about is carp. There are many species of carp across the world and within North America. There are no native carp species in North America; they were all brought in within the last 200 years or so. The carp that plague our waters are originally from Europe and Asia. Each species mentioned in this blog eats something different, one eats aquatic plants, a few eat plankton, some eat mussels and aquatic snails all of which further impact and degrade the aquatic diversity and ecology of our lakes, river, and streams. These fish include the common carp; sliver carp, grass carp, bighead carp, and black carp. I plan to describe each of these species, give a little bit of background and how you can catch and use/eat them if you find yourself catching one.
1. The Introduction of Carp Into North America
As I briefly mentioned above, carp were introduced into North America in the 1800’s. The people introducing this fish were immigrants. The National Park Service wrote an article on the history of common carp in North America called, History of Common Carp in North America, which states, “Inspired by the European model (whereby the Austrian princes of Schwarzenberg maintained 20,000 acres of carp ponds), scattered entrepreneurs began to import the prized fish, hoping to provide a familiar, profitable food staple to the rapidly growing nation. Julius A. Poppe was one of the most successful, expanding a stock of five common carp imported from Germany in 1872 into a thriving California farm by 1876. Fielding orders from throughout the country, he actively began to lobby for national cultivation of the hearty fish… Faced with such public pressure to make carp more widely available and the worrisome decline of native fish stocks after a century of intense exploitation, the U.S. Commission of Fish and Fisheries began an intensive effort of carp cultivation in 1877. Subsequent efforts by state Fish Commissions had introduced the carp to many area waters by 1883, and the fish’s remarkable ability to live and reproduce in most every water condition allowed it to quickly infiltrate others”. Europeans were the ones who introduced this species of fish to North America and promoted its expansion, though this mindset changed only a few decades later when people began to see the effects of the introduction.
The other five species of carps were introduced in the 1970’s due to flooding of aquaculture ponds where the species were either placed on accident due to misidentification or as a way to control pond algae and plankton in the ponds. After the flooding, they were then able to reach the Mississippi river and migrate across the United States.
2. Common Carp
The common carp was the first carp species to be introduced to North America. It is a fish that is cherished globally for its fierce fighting in the water when caught while fishing and its eating across Europe in Asia. In the U.S. it is common to have people catch this fish to use either as bait for other fish such as gar or catfish or just leave it on the bank to rot. This is a common trend with many other carp species, as well as various native gar species for some reason. This fish is established in rivers and lakes in every state within the lower 48. These fish are scavengers and will eat plants, decaying material, and aquatic invertebrates. These fish can out-compete other species and cause bank erosion in the waters they reside, they are also the same type of fish as the koi fish found in people’s garden ponds, koi are just ornamental versions.
3. Silver Carp
Silver carp are described as swimming in large clusters/groups of fish called schools. They are extremely strong fish and have been documented leaping out of the water when there is a loud sound or commotion in the water. There are cases of these fish injuring boaters when jumping out of the water as they have hit the boaters in the face. This fish species was imported to help maintain/control of algal blooms and plankton in aquaculture ponds, much like the bighead carp. Silver carp lack a true stomach and are able to constantly feed since they feed mostly on plankton. Silver carp can grow to be pretty big. They have been noted to be upwards of three feet.
4. Grass Carp
Grass carp are given their name because well, they eat grass. They also eat decaying plant matter and insects. Grass carp prefer to live in slow moving streams and lakes/pond. Grass carp are such great eaters and plant removers that federal and state agencies still use the fish as a means to help with the prevention and removal of nuisance vegetation within fisheries or aquaculture facilities. Prior to placing the fish within their ponds/tanks the fish must be made and proven sterile as to prevent the fish from spreading further as the grass carp are only found in 45 of the 50 United States.
5. Bighead Carp
Bighead carp are noted as being strong feeders. They primarily eat plankton and decaying plant matter. Since they eat so much and so often they often out-compete other native species in their larval stage as well as mussels and the paddlefish which solely filter feeds on plankton. Bighead carp also lack a true stomach due to their method of feeding. Typically animals that filter feed lack true stomachs. These fish are found commonly throughout any region that is connected to the Mississippi river which includes a decent portion of the United States. These fish get big and are distinguished by their large heads and dark splotches on their sides.
6. Black Carp
Black Carp are known to look similar to that of grass carp. Though, black carp typically have a darker tone to their scales despite not actually being black in appearance. The similarity in appearance is how this fish accidentally made its way into the United States as it was mistaken as a young grass carp. This species of carp is known for having a diet of mussels and snails. This is worrisome as many states have endangered or threatened native mussel/snail species. This is due to the degradation of water quality, habitat loss, and competition with invasive species such as the zebra mussel. This fish has actually been considered as a means to help control zebra mussel populations, though it was overlooked based on the fact that the fish lacks the physiology to be able to crush and consume the small, hard shells of the mussel.
7. Making The Most of Carp
Carp are a sought after fish in various parts of the world. In the United States you will rarely see people actively fish for these animals, but you may see someone bowfish for them. This is due to many reasons. One being the types of environments these fish can live and flourish. These fish can reside in waters that many native fish cannot due to sediment in the water and the amount of pollution/toxicity. This gives them an association with being full of toxic chemicals/pollutants, which can be the case in some areas so make sure you research that before if considering eating. Another reason is that the fishes are not eaten here is because the way we often cook/eat fish in the U.S. is different than other countries. Here anglers tend to prefer boneless fillets that are ready to be either battered and fried or oiled and grilled. These fish have Y bones all along their spines and fillets, making it laborious to descale and debone these fish. In other countries this isn’t as big of an issue as you either prepare the fish as a stew so the meat falls off of the bones or you eat it with your hands as a curry and pick out the bones as you go. Another option I would consider if you aren’t too keen on eating these fish would be to use them as fertilizer in your garden. This may seem cruel at first, but Native Americans have been using fish as fertilizer in their gardens for ages. These fish have no problem reproducing and remain a threat in our waterways; this is a great way to utilize the resource and improve the fertility of your garden organically.
The history of carp in the United States is not commonly discussed. As a fisherman, you commonly see carp and understand that they are not native to the region, but some grass carp have become naturalized meaning that they are now in balance within their local ecosystem. Many fishermen hold a grudge against this fish, though they do not understand how they made their way into our waters. It is a story that we as humans have made time and time again. To me it is an example of the consequences that we have made based on short sighted ecological actions that I am sure we will continue to make sadly. The fishes aren’t all bad though, they are an untapped resource that could potentially help feed America during hard times and are fun to fish for due to their size and ability to put up a fight. There are many ways we can utilize this new resource besides letting it go to waste on a river bank or in a landfill. I hope whoever is reading this may consider fishing for carp in the future and either cooking it for dinner or using the fish as fertilizer in your garden for a lush yield.
“History of Common Carp in North America.” National Parks Service, U.S. Department of the Interior, https://www.nps.gov/miss/learn/nature/carphist.htm.