Cyprinus is a collective term for cyprinus fish in the family Cyprinus, native to Eurasia, there are 10 extant species, the European carp (Cyprinus carpio) is a model species, and the mirror carp and the leather carp are its variants. The most common native carp in China is the South China carp (Cyprinus rubrofuscus), and the koi is its variant.
In the 5th century BC, Fan Li's "Fish Farming Classic" recorded the method of raising carp, but the carp later failed to enter the list of "Four Great Fishes in China", but its status in the culture was higher than that of the "Four Great Fish", "Rich and Noble", "More than a Year", the image is mostly carp, and the folk widely spread the saying that carp jumps the dragon gate. In the West, carp farming dates back to Roman times, and European monks raised carp as food fish in the 13th-16th centuries, but Westerners did not accept carp very much, from ancient times to the present.
Carp has been introduced into farming in about 59 countries and has spread to all continents except Antarctica. In the absence of natural predators or large-scale commercial fishing and consumption markets, carp often enter wild waters as a party to the pest, and due to their high reproductive rates and feeding habits in sediments, they may widely alter the local environment, reduce the clarity of the waters, destroy aquatic plants, reduce the bait and habitat of native aquatic animals, and also bring a large number of pathogens and parasites, threaten native species, causing disasters in asia, Europe, Africa, North America, South America, Oceania, And Africa, and are listed as " The World's Top 100 Invasive Alien Species".
The story of carp making waves in the United States is a cliché, but another country where carp are tortured is rarely mentioned: Australia. Perhaps there are too many invasive species in Australia, with rabbits, foxes, cats, wild boars, mice, goats, dromedaries, etc. grabbing headlines, resulting in low attention from carp.
European carp was introduced to Australia in the 1860s and did little for the first hundred years until the 1974 flood in Australia, which took advantage of the flood to spread across the Murray-Darling River Basin and gradually flooded.
In 1996, Fujian Aquatic Products published an article entitled "Australian Carp Breeding Disaster": It is estimated that there are 8 billion carp in the Murray-Darling River Basin, australia's largest water system, which is the largest number of fish species in Australian rivers.
The figure of "8 billion tails" is exaggerated, but it can also be seen that carp are super fertile and have successfully occupied Australia's rivers just over two decades after the 1974 floods.
Recently, researchers have calculated the number of carp using more scientific measurement methods. The researchers collated information on the catch of 574145 carp caught at 4831 sites and speculated that carp in southeastern Australia accounted for 96% of its total biomass and 92% of the total available wet habitat area. In the "average" hydrological case, the number of carp is estimated at 200 million, and in the "wet" case, the number of carp is estimated at 357 million, up to a maximum of 685 million. In south-east Australia, carp biomass can reach 205774 tonnes in "average" hydrological conditions, up to 368357 tonnes in "wet" conditions and up to 705 630 tonnes, with maximum biomass densities of up to 826 kg/ha, far exceeding the accepted biodiversity threat threshold of 80-100 kg/ha.
Australians certainly don't tolerate so many carps making waves in rivers, and for decades have come up with a variety of ways to eliminate carp, such as bounty money to encourage people to fish, set up nets in the river, use carp as fertilizer, and stock some genetically modified carp that can only produce male offspring, but the effect is very weak, and in 2016 a seemingly very powerful plan was proposed - the use of herpes virus KHV to eliminate carp.
Scientists at Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) spent seven years investigating the potential of a strain of herpes virus against carp in eliminating carp. Rigorous testing has shown that the virus effectively prevents carp from breathing by attacking their kidneys, skin, and gills, dying within 24 hours of symptoms. The virus removes 70%-80% of carp populations, but does not harm native aquatic animals. The plan, which cost $15 million, began implementation in 2018, but was not implemented on time due to ongoing controversy.
An article published in the October 2020 journal Applied Ecology, "The Australian carp virus plan 'dead in the water', shows that new research from the University of Exeter and the University of East Anglia confirms that carp evolve resistance to the virus and that carp populations will soon recover. Dr Jackie Lighten of the University of Exeter said: "Viral biological control is very questionable and, as our research suggests, it is unlikely to reduce carp populations in the long run. ”
After the plan to release the virus was abandoned, the hope of eliminating carp became even less bleak.
Europeans and Americans have a low level of acceptance of carp, preferring to eat fresh and tender marine fish, hating carp's intermuscular spines, and scorning carp and other carp freshwater fish. In the United States, there are countless cases of lawsuits in restaurants every year because they get stuck in fish bone fish bones, and it is impossible to expect them to eliminate carp with their mouths. Many people on the domestic network say that carp is delicious, like to eat carp, but also said that they are willing to help the United States and Australia eliminate carp, most of these are just for ridicule, ridicule, not many really like to eat carp.
It is impossible to destroy carp by Chinese mouth.
According to the China Fishery Statistics Yearbook, china's farmed carp production in 2016 was 3497967 tonnes, ranking third among freshwater fish, after grass carp and silver carp. While global carp production in 2016 was 4556621 tons, and China's carp production accounted for 76.8% of the world's carp production, and there is no need to watch carp in foreign rivers drool.
In 2012, Yu founded two rivers fisheries in Kentucky, which fished for "Asian carp" in the United States and processed it for export to China, exporting 227 tons to China from August to December 2013 and 453 tons from January to September 2014. But it doesn't sell well in the country because it's too expensive, frozen fish don't taste good, or some people are afraid of heavy metals exceeding the standard.
The elimination of invasive species is a worldwide problem, China is also deeply affected by invasive species, China currently has more than 660 species of invasive alien species, causing an annual loss of 200 billion yuan.