CATDOLL : CATDOLL: Taihu whitebait was once introduced to 21 provinces, so why does no one dare to raise it now?

Taihu whitebait was once introduced to 21 provinces, so why does no one dare to raise it now?

Taihu whitebait was once introduced to 21 provinces, with an annual profit of 70 million yuan. Why does no one dare to breed it now? Aquaculture has always been one of the important industries in my country. This industry alone can generate hundreds of billions of yuan in revenue each year, driving many people to become rich, and the name of Taihu whitebait was also known for this. At the end of the 20th century, the West Taihu whitebait began to show its prowess. Many fishermen made a lot of money with this fish. Some people found it profitable and flocked to it, so it was given the title of little gold. However, I believe that many people have noticed that the Taihu whitebait, which once created countless legends, is now gradually declining, and basically no one dares to breed it. Why is this?

First, Taihu whitebait, also known as noodle fish and silver bar fish, is a freshwater fish and a small economic fish that is unique to my country. It has a slender body, silver color, fresh and tender meat, no phosphorus and no words, the whole fish is edible, and it is rich in nutrients, containing protein, fat, iron, riboflavin, calcium, phosphorus and many other kinds. It has a high economic value and is known as the queen of fish. In the 1970s, in addition to Japan, many foreign countries traded whitebait with my country, making it an important export and foreign exchange earning variety for my country. Earlier, whitebait was only cultivated in Taihu Lake, but in 1979, Taihu whitebait was transplanted to other places for the first time, and fishermen in Dianchi Lake became the first to try it. In 1985, the output of whitebait in Dianchi Lake successfully exceeded that of Taihu Lake, generating economic benefits far exceeding 70 million. Seeing the success of whitebait in Dianchi Lake, more and more places have gradually started to think about surplus, and since then, a wave of transplanting whitebait has been set off in China. The whitebait from Taihu Lake have been transplanted to 21 different provinces across the country, including Taiwan and Shaanxi.

Second, the price of domestic tours ranges from 25 to 60 yuan per catty. A good one catty costs hundreds of yuan. A fish can create an output value of tens of millions of yuan in the 1990s. Such a large profit is indeed enough to drive people crazy. In addition, the adaptability and reproductive capacity of silverfish are not weak. They can reproduce naturally, with a carrying capacity of about three thousand meters. They do not need to be released every year. The breeding cost is low, and they can generally reproduce quickly within five months. For various reasons, a silverfish has become a violent attack. However, it is worth noting that Taihu silverfish does not refer to a single fish, but includes Taihu shortnose silverfish, oligodont shortnose silverfish, big silverfish, Lei's silverfish, and Taihu new silverfish. Among them, the most economically valuable are Taihu new fish and big silverfish, which are also the two widely cultivated by everyone. Although silverfish have their own advantages, not every transplant can guarantee success.

Third, it is understood that the cost of every 10,000 fertilized eggs of whitebait is about 50 yuan, and the cost of 10,000 mu of water area is about 170,000 yuan. It seems that the cost is very high, but once the transplantation is successful, this cost seems to be insignificant. However, if the placement fails many times, it will eventually lose all the money. Inner Mongolia Dahai is a typical example. The first time the sea was in English, it was very smooth, and the output gradually increased. Soon, a considerable fishing output was formed, but what caught people off guard was that the whitebait in the lake disappeared without any warning, causing heavy losses to the local area. In 2016, the population of large whitebait in a city in Heilongjiang also ushered in an outbreak, but at that time, the male and female fish could not complete mating, resulting in a sharp drop in production. The whitebait industry, which was lost by various accidents, fell into a trough again.

Fourth, studies have shown that the success rate of natural hatching of whitebait is very low, and the water quality requirements are very high. Once the water environment is abnormal, the whitebait eggs may not hatch, and eventually the entire population will be wiped out. The breeding cost and technology are very high. To be on the safe side, fishermen will not choose to breed. In addition, Taihu whitebait has the habit of swallowing fish eggs, small fish and shrimps, causing the native fish to disappear after the seed box. From this, it can be seen that although Taihu whitebait has brought huge economic benefits, it also poses a threat to the entire ecosystem.

Because the transplant success rate of Taihu silverfish is very low and it is very easy to lose money, no one dares to raise them now.

This is because this fish eats a lot, which will cause all the local plants to be eaten up, so many cities dare not introduce it.

Because this kind of fish seems to be listed as a national protected animal now, and you cannot sell it even if you raise it, otherwise it would be an illegal act.

Will silverfish freeze to death in water in winter?

Silverfish will not freeze to death in the water in winter. Fish are cold-blooded animals with a high purine content in their bodies, and they can convert and metabolize energy normally even in very cold water. Only a few species of fish will freeze to death, such as tilapia, because they are tropical fish and are not suitable for the cold in the north. Fish in the cold zone of the real north will not freeze to death. If a fish dies in the ice, it is not because of freezing, but because the ice cannot provide the fish with enough oxygen, and they die of lack of oxygen.

Silverfish like to live in the middle and lower layers of water bodies. The fry have a strong tendency to phototaxis. Young fish generally feed on plankton or its metabolites. Only when the silverfish grow to a certain size can they ingest some smaller organisms. Mature silverfish will reproduce around the beginning of winter, which usually lasts for three or four months. They will die within a short time after spawning. The death will be more serious if the water lacks oxygen.

Fish are cold-blooded animals, and their body temperature changes with the temperature of the surrounding environment. Therefore, in winter, fish live in cold water, and because their body temperature is low, they do not feel cold.

In the pond in winter, the fish still swim leisurely. Aren’t they afraid of the cold?

It turns out that fish use their own blood to regulate their body temperature and adapt to temperature changes. The body temperature of fish changes with the water temperature. When the water is very warm, the body of the goldfish will also become very warm; when the water becomes cold, the body temperature of the goldfish will also drop, roughly the same as the water temperature. Fish are very adaptable to water temperature, so they can live healthily in cold climates at freezing points or in hot summers over 30℃. Moreover, the reproductive function of fish is more developed in low temperatures; if they are kept warm all year round, it will cause them to be unable to lay eggs.

In the cold winter, many creatures such as whitebait and Antarctic cod can still survive when their body fluids reach -2 degrees Celsius. It turns out that they all produce antifreeze proteins to help them survive in icy water. This antifreeze protein prevents the formation of large amounts of ice crystals by attaching to ice crystals and forcing them to change shape - just like putting a stone on a pillow and the pillow will deform. In this way, even if the temperature inside the fish is below zero, the body fluids will not turn into ice crystals due to the action of antifreeze proteins, and the fish can survive.

Every animal has a temperature limit that it can tolerate, but the tolerance is different. For example, the suitable temperature for tropical fish is relatively high, and they can't stand it if it's too cold. There are also fish such as whales and toucan fish living under the sea where the sun can't reach. The lower limit of the temperature they can tolerate is relatively low, but once the temperature is lower than the lower limit of the temperature they can tolerate, they will still be unable to stand it and freeze to death.