Asian carp is a general term for the four major fish in the United States: silver carp and other invasive fish. As early as the 1970s, Asian carp was introduced to the United States as a kind of fish to clean algae, and it is said that the effect is not bad.

However, the local people soon realized that this was wrong. These four kinds of big fish have become more and more local by virtue of their super reproductive ability and the nature of eating everything, while there are fewer and fewer local fish, and even many of them have disappeared.

According to local media reports, Asian carp seems to be a food blender. Whether it is aquatic plants or aquatic plants on the shore, whether it is fish eggs or small fish and shrimp, it can be their food. So that local fish are endangered because they can't catch the corresponding food.

In addition, the jumping ability of Asian carp is also amazing. In China, it has been called "carp yue longmen" since ancient times, but in the United States, they have also developed this characteristic, and they can jump out of the farm and enter the local natural water system.

For decades, Asian carp have been found everywhere in the large and small basins of the Mississippi River in the United States. Although no one has specifically counted their numbers, there is no doubt that they definitely exceed10 million.

Asian carp make waves

Asian carp can flood in the United States because of three conditions.

The first condition is their amazing reproductive ability. Different from mammals, Asian carp are fertilized in vitro, and neither females nor males participate in reproduction, so their egg production is very high, reaching more than 5 million at a time. In China, there are many natural enemies of Asian carp, which can kill some eggs of Asian carp, so that the survival rate of larvae is not high and the population remains in a relatively stable range.

The lack of natural enemies in the United States and the strong adaptability of Asian carp to the environment have led to a very high hatching rate of fish eggs, enabling them to grow rapidly in the wild.

The second condition is the lack of local natural enemies, which is one of the main reasons why almost all invasive species can flood.

The third condition is the amazing adaptability of Asian carp. They can adapt to both high-temperature waters and cold rivers, and their upstream nature makes them spread to other areas along the river and flood in other water systems.

When there are no rivals in nature, Asian carp will tell us what species invasion is in an amazing gesture. Herring in Asian carp will attack the fry, mussels and snails of local fish, which are one of the important economic sources of local fishermen and bring huge economic losses to local fishermen.

In addition, due to the suitable environment and no natural enemies, the fish here are huge, reaching an astonishing 50 kg, which is difficult to achieve in China.

The huge gesture also threatens the safety of local fishermen and tourists. Silver carp in Asian carp like to live above the water, and they are particularly vulnerable to fright. When they are frightened, they will jump out of the water, which may attack tourists and even damage the ship, threatening the lives of the people on board.

How to eliminate them?

Because Asian carp continue to commit crimes in the local area, so that the local people can't stand it, the US government even issued a killing order against them, prohibiting the transportation of live Asian carp for any reason, prohibiting the release of Asian carp without permission, and executing them immediately once found.

In addition, people have set up a carp shooting competition, which attracts many participants every year, but this method can not completely eradicate the problem of carp flooding in Asia.

China foodies may say that bringing chefs from China can solve the problem of carp flooding in Asia, but this method is not easy to use. Locals have also developed many recipes, but Asian carp contains a lot of intermuscular spines, which has a strong earthy smell and is disliked by locals. Therefore, the local price of Asian carp is very low, and fishermen are willing to kill this kind of fish only by government subsidies.

Most of the captured Asian carp will be crushed and used as animal feed, but this can only control their number, but it can't cure the problem of Asian carp flooding.

At present, the problem of Asian carp flooding is still a headache in the United States. Some people even want to set up an acoustic bubble wall to stop the invasion of Asian carp, but this project is costly and has not been implemented yet.

abstract

Many people think that the reason why the "Four Big Fish" didn't flood in China is that China eats a lot of food, which can quickly eliminate their numbers. But this is not the case. The four major fish have evolved in China for many years, and have already had their natural enemies in the local ecological chain, such as mandarin fish and snakehead. With the control of natural enemies, the number of the four big fish can be kept in a relatively stable range.

In addition, there are other local fish competing for food with them, which further inhibits their number and size. So that most of the four big fish caught in China are not big, but in the United States, the weight of the four big fish is like a pig.