Grass Carp Fish

The Grass carp fish (Ctenopharyngodon idella) is a popular carp fish species which is cultivated throughout the world. It’s largest reported production is over five million tones per year globally.

It is native to eastern Asia, and is a large herbvorous freshwater fish species of the Cyprinidae family. And it is the only species of the genus Ctenopharyngodon. It’s native range is from northern Vietnam to the Amur River on the Siberia-China border.

Grass carp fish is cultivated in China for long time for food. But it was also introduced in the United States and Europe for aquatic weed control.

This fish species is mainly found on turbid rivers and associated floodplain lakes. It is also called White Amur in the United States (which is derived from the Amur River, where this fish is probably native but has never been abundant).

But it is not to be confused with the white Amur bream, which is not a particularly close relative. The Grass carp fish species has been introduced to many countries and available throughout the world.

Countries and territories in the Northern Hemisphere where this fish is available include India, Bangladesh, Israel, Japan, Taiwan, Mexico, Malaysia, the Philippines, the United States, the Netherlands, Denmark, Romania, Switzerland, Czechoslovakia, Sweden, Yugoslavia, Italy, West Germany, the United Kingdom, Poland and France.

And in the Southern Hemisphere, they have been introduced to South Africa, Argentina, Fiji, New Zealand, Venezuela and Australia.

Grass Carp Fish Full Information

Grass carp fish species was first imported in the United States in the year of 1963 from Taiwan and Malaysia to aquaculture facilities in Alabama and Arkansas.

The first release is believed to have been an accidental escape in 1966 from the US Fish and Wildlife Service’s Fish Farming Experimental Station in Stuttgart, Arkansas, followed by planned introductions beginning in 1969.

The species had been introduced to 40 states by the 1970s, and it is still stocked in many states as an effective biocontrol for undesirable aquatic vegetation. Read some more information about the Grass carp fish below.

Characteristics

Body of the Grass carp fish is elongated, chubby and torpedo-shaped. Color of the body is dark olive, shading to brownish-yellow on the sides, with a white belly and large, slightly outlined scales.

The terminal mouth is slightly oblique with non-fleshy, firm lips and no barbels. The complete lateral line of these fishes contains 40 to 42 scales.

They have broad, ridged, pharyngeal teeth which are arranged in a 2, 4-4, 2 formula. Their anal fin is set closer to the tail than most cyprinids, and the dorsal fin has eight to 10 soft rays.

The Grass carp fish can grow very large in size. Their average body length is between 60 and 100 cm, with a maximum length of around 1.4 meters. And they can grow as much as 40 kg.

Appearance

Grass carp are easily recognizable by their long, cylindrical body shape and large scales. They have a dark green or brownish back and a pale belly, with a distinctive golden sheen along the sides.

Their dorsal fin is set far back on their body, and they have a large, wide tail fin. They lack teeth in the front of their mouth, but have several rows of pharyngeal teeth in the back of their throat that they use to crush and grind plant material.

grass carp fish, grass carp fish appearance, about grass carp fish, grass carp fish facts, grass carp fish farming, grass carp fish info, grass carp fish images, grass carp fish lifespan, grass carp fish photos, grass carp fish pictures, grass carp fish size, grass carp fish uses, grass carp fish weight

Size

Grass carp can grow quite large, with some individuals reaching lengths of up to 4 feet and weights of up to 100 pounds. However, in pond and lake environments, they typically grow to be around 20-30 inches long.

The growth rate of grass carp is influenced by a variety of factors, including water temperature, food availability, and stocking density.

Behavior

Grass carp are generally solitary fish, although they may form loose aggregations during spawning season. They are most active during the day, and tend to be less active at night.

Grass carp are very mobile, and are capable of covering long distances in search of food or suitable habitat. They are able to tolerate a wide range of water temperatures and conditions, and can survive in environments with low dissolved oxygen levels.

Ecological Impacts

While grass carp are effective at controlling aquatic weeds, introducing them to new environments can have negative ecological impacts.

In some cases, they have been known to escape from ponds and lakes and establish populations in nearby rivers and streams, where they can compete with native fish species and disrupt aquatic ecosystems.

For this reason, many states have strict regulations on the stocking of grass carp in public and private waters.

Feeding

Grass carps primarily feed on plant material, it is important to provide them with a well-balanced diet to ensure their health and growth. Here, we will discuss some of the key considerations for feeding grass carp.

Natural Diet

In their natural environment, grass carp feed on a variety of aquatic plants, including species like duckweed, water hyacinth, and cattails. They use their powerful pharyngeal teeth to grind and crush the plant material, which is then fermented and broken down in their gut.

Grass carp have a very efficient digestive system that is specialized for processing plant material, and they are able to convert the nutrients from their food into body mass very efficiently.

Commercial Diets

In aquaculture settings, grass carp are typically fed a commercial diet that is formulated to meet their nutritional needs. These diets are usually made from a combination of plant-based ingredients, including soybean meal, corn, wheat, and rice bran.

They are designed to be high in fiber and low in fat, to mimic the nutrient profile of the fish’s natural diet. Some commercial diets also contain vitamin and mineral supplements to ensure that the fish receive all the nutrients they need.

Feeding Schedule

Grass carp should be fed regularly to ensure their growth and health. In general, they should be fed 1-2% of their body weight per day, divided into two or three feedings.

It is important to avoid overfeeding, as this can lead to excessive nutrient buildup in the water and can contribute to water quality problems. It is also important to monitor the fish’s growth and adjust the feeding rate as needed.

Feeding Techniques

There are several different techniques that can be used to feed grass carp. In small ponds or tanks, the fish can be hand-fed with a pelleted diet. In larger ponds or lakes, automatic feeding systems can be used to distribute the feed at regular intervals.

It is important to ensure that the feed is distributed evenly across the pond, to prevent overfeeding in certain areas.

Supplementary Feeding

In addition to their regular diet, grass carp can also be given supplementary feedings of fresh or frozen fruits and vegetables. Some good options include lettuce, spinach, apples, and oranges.

These foods can be tied to a string and suspended in the water to encourage the fish to feed on them. It is important to avoid feeding sugary or high-fat foods, as these can be harmful to the fish’s health.

Breeding

If you are interested in raising grass carp, it is important to understand the basics of their breeding biology. Grass carp fish generally enter reproductive condition and spawn at temperatures of 20° to 30° C.

Breeding Season

Grass carp are typically sexually mature at around 2-3 years of age, although this can vary depending on environmental conditions and other factors. The breeding season for grass carp generally occurs in the late spring or early summer, when water temperatures are warm and the days are long.

During this time, male fish will begin to develop tubercles (small bumps) on their head and body, and females will become noticeably plump with eggs.

Breeding Techniques

There are several different techniques that can be used to breed grass carp. In natural breeding systems, male and female fish are allowed to spawn naturally in a pond or lake. In aquaculture settings, however, many farmers use artificial breeding techniques to ensure successful reproduction.

One of the most common techniques for grass carp breeding is hormonal induction. This involves injecting female fish with a hormone called human chorionic gonadotropin (HCG), which stimulates ovulation.

Once the females have been injected, they are paired with males in a spawning tank or pond, and the fertilized eggs are collected and incubated until they hatch.

Another technique that can be used for grass carp breeding is the use of a spawning mat. This involves placing a specially designed mat in the water, which the fish will spawn on. Once the eggs have been laid on the mat, it can be removed and the fertilized eggs can be incubated.

Incubation and Hatching

Once the eggs have been fertilized, they must be incubated until they hatch. Grass carp eggs typically take 4-10 days to hatch, depending on water temperature and other factors. The eggs can be incubated in a variety of different ways, including in a specialized hatching tank or in a floating incubation basket.

Once the eggs have hatched, the newly hatched fry will need to be fed a specialized diet of planktonic organisms until they are large enough to consume commercial fish food. This process can take several weeks or even months, depending on the size and growth rate of the fish.

Uses

The Grass carp fish is cultivated mainly for food in many countries. And it is used for aquatic weed control in some countries. Here we are listing the top uses of these fish.

Pond and Lake Management

One of the most common uses of grass carp is in pond and lake management. These fish are excellent at controlling aquatic vegetation, particularly submerged weeds like hydrilla and curly leaf pondweed.

By consuming these plants, grass carp can help to maintain water quality, reduce the risk of algal blooms, and improve aquatic habitat for other species.

It is important to note, however, that grass carp should be used carefully and in appropriate situations. Overstocking of grass carp can lead to overgrazing and destruction of beneficial aquatic vegetation, which can have negative impacts on other aquatic species.

Food Fish

Grass carp are also an important food fish in many countries, particularly in East Asia. In China, grass carp is the second most commonly farmed freshwater fish species after the Chinese carps. The fish can be prepared in a variety of ways, including steaming, grilling, and stir-frying.

In addition to their use as a food fish, grass carp are also important in the ornamental fish trade. They are often sold as live fish for use in backyard ponds or aquaria.

Research

Grass carp are also important in research settings. Scientists have used these fish to study a variety of topics, including fish nutrition, behavior, and physiology. Because of their relatively large size and fast growth rate, grass carp are a popular model species for research on fish growth and development.

Challenges

While grass carp have many uses, they also present some challenges. One of the biggest challenges is the potential for these fish to escape from aquaculture facilities and become invasive in natural waterways. This can lead to negative impacts on native aquatic species and habitats.

In addition, grass carp are known to be difficult to spawn and rear in captivity, which can limit their availability for use in aquaculture or research. Finally, there is some concern that the introduction of grass carp as a biological control agent could have unintended consequences, such as the overgrazing of beneficial aquatic vegetation or the introduction of disease.

Special Notes

The Grass carps grow very fast. Fingerlings stocked in the spring at 20 cm, will generally reach over 45 cm by fall.

According to one study, average lifespan of these fish is between 5 and 9 years (with the oldest recorded surviving for 11 years).

There is a thriving population of Grass carp fish passing the 15 year mark in Silver Lake Washington. In natural condition, these fish require long rivers for the survival of the eggs and very young fish.

This fish may be baked, steamed, broiled and pan-fried for eating. However, review full breed profile of the Grass carp fish in the following chart.

NameGrass Carp
KingdomAnimalia
PhylumChordata
ClassActinopterygii
OrderCypriniformes
FamilyCyprinidae
SubfamilyLeuciscinae
GenusCtenopharyngodon
SpeciesC. idella
Binomial NameCtenopharyngodon idella
Other NamesKnown as White Amur in the United States
Breed PurposeFood, aquatic weed control
Special NotesGrow very fast, 5-9 years average lifespan, require long rivers for the survival of the eggs and very young fish in natural conditions, very common throughout the world
Breeding MethodNatural and artificial
WeightCan grow around 40 kg
Water TypeFreshwater
Climate ToleranceAlmost all climates
Body ColorDark olive, shading to brownish-yellow on the sides with a white belly
RarityCommon
AvailabilityWorldwide

Grass Carp Fish Interesting Facts

Here are some interesting facts about grass carp fish:

  1. Grass carp are the only species in their genus.
  2. They are native to rivers and lakes in East Asia, but have been introduced to many parts of the world, including the United States.
  3. Grass carp are herbivorous, feeding primarily on aquatic vegetation. They are known for their ability to consume large amounts of vegetation, up to 40% of their body weight in a day.
  4. They can grow up to 4 feet in length and weigh over 100 pounds, although most individuals are smaller.
  5. Grass carp are known for their distinctive appearance, with a large head, elongated body, and silver scales.
  6. They have a long lifespan, with some individuals living up to 15 years in the wild.
  7. Grass carp are social animals and tend to travel in groups.
  8. They are popular sport fish in many parts of the world, with anglers targeting them for their size and fighting ability.
  9. Grass carp have been used as a biological control agent for aquatic weeds for over 50 years, and are a preferred alternative to chemical control methods.
  10. While grass carp are known for their herbivorous diet, they have been known to eat small fish and crustaceans in certain circumstances.
  11. Grass carp are sometimes called “white amur,” which is a misnomer since they are not related to true amur species.
  12. In China, grass carp are the second most commonly farmed freshwater fish species after the Chinese carps.
  13. Grass carp have been hybridized with other carp species to create new varieties, including the “golden cross” which is a hybrid of grass carp and silver carp.
  14. Grass carp have a complex reproductive cycle, with females producing up to 1 million eggs each year. However, successful breeding in captivity can be difficult.
  15. Grass carp are an important part of many aquatic ecosystems, helping to maintain water quality and providing food for predators such as birds and larger fish.

Frequently Asked Questions

People ask many questions about Grass carp fish. Here we are trying to list the most common questions about this freshwater fish species and trying to answer them. Hope you will find your answer. Don’t hesitate to ask us if you have more questions.

What is a grass carp fish?

Grass carp (Ctenopharyngodon idella) is a freshwater fish species that is native to Asia. It is a type of carp that feeds primarily on aquatic plants and is commonly used for weed control in ponds and lakes.

How big do grass carp fish get?

Grass carp can grow quite large, with some individuals reaching lengths of up to 4 feet and weights of up to 100 pounds. However, in pond and lake environments, they typically grow to be around 20-30 inches long.

What do grass carp fish eat?

As mentioned, grass carp feed primarily on aquatic plants. They are particularly effective at controlling submerged and emergent vegetation, including species like duckweed, water hyacinth, and cattails.

Can you eat grass carp fish?

While grass carp are not typically raised for food in the United States, they are considered a delicacy in some parts of Asia. The flesh is said to be tender and sweet, but it can be difficult to prepare and has many small bones.

How do you catch grass carp fish?

Grass carp can be caught using a variety of methods, including baited hooks, nets, and traps. However, because they are primarily herbivorous, traditional fishing techniques that rely on live or artificial bait are less effective. Many anglers use specialized grass carp baits made from dough or soybeans.

Can grass carp fish reproduce in ponds?

Yes, grass carp can reproduce in ponds and lakes under the right conditions. However, in most cases, they do not reproduce successfully in small, confined environments like backyard ponds. In fact, many states require that grass carp be sterilized before they are stocked in private ponds to prevent overpopulation.

Are grass carp fish good for controlling weeds in ponds?

Yes, grass carp are highly effective at controlling aquatic weeds in ponds and lakes. They are particularly useful for controlling submerged and emergent vegetation, which can be difficult to remove using mechanical or chemical methods. However, it is important to stock ponds with the appropriate number and size of grass carp to ensure effective weed control without overgrazing.

Are there any concerns about introducing grass carp fish to new environments?

Yes, introducing grass carp to new environments can have negative ecological impacts. In some cases, they have been known to escape from ponds and lakes and establish populations in nearby rivers and streams, where they can compete with native fish species and disrupt aquatic ecosystems. For this reason, many states have strict regulations on the stocking of grass carp in public and private waters.

How long do grass carp fish live?

Grass carp can live for up to 15-20 years in the wild, although their lifespan is typically shorter in pond and lake environments.

What are the characteristics of Grass carp fish?

Body of the Grass carp fish is elongated, chubby and torpedo-shaped. Color of the body is dark olive, shading to brownish-yellow on the sides, with a white belly and large, slightly outlined scales. The terminal mouth is slightly oblique with non-fleshy, firm lips and no barbels. The complete lateral line of these fishes contains 40 to 42 scales. They have broad, ridged, pharyngeal teeth which are arranged in a 2, 4-4, 2 formula. Their anal fin is set closer to the tail than most cyprinids, and the dorsal fin has eight to 10 soft rays. The Grass carp fish can grow very large in size. Their average body length is between 60 and 100 cm, with a maximum length of around 1.4 meters. And they can grow as much as 40 kg.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top