A few days ago, the news about the invasion of Sichuan by sunfish was once again mentioned. Some fishing media published an article saying that recently, when an angler fished in the reservoir, he caught a large number of sunfish, and the size is not small. At the same time, the article said that the sunfish is menacing and has been found in many places in Sichuan.
Sunfish are native to the freshwater waters of the southern United States and northern Mexico and are alien species in the country. A fisherman who has been active in the fishing circle for a long time said that at present, there are traces of sunfish in many large reservoirs in Sichuan.
Zhang Zhiying, director of the Fishery Administration Department of the Sichuan Provincial Fisheries Bureau, who has been engaged in fishery administration management for more than 30 years, said that at present, there are indeed sunfish in Sichuan, but the number is not huge, and it will not flood for the time being. "During the next decade of the fishing ban period, we will also increase the monitoring and assessment of various aquatic populations, including alien species."
Sunfish
"The spines are less like marine fish, we shout 'garlic cloves'." An angler said.
The staff of the Fisheries Research Institute of the Sichuan Academy of Agricultural Sciences said that sunfish can be eaten, but it is certainly not possible to prevent flooding by eating. In addition, there have been examples of artificial cultivation of alien species for food before, such as the commonly known as "barracuda", whose scientific name is spotted forktail catfish, native to the North American continent, and was later introduced into the country and realized artificial breeding for food.
25 yuan a pound of vegetable market has to sell,
But not every day
"Wuchang fish 17 yuan a pound, duobao fish 35 yuan a pound, catfish 13 yuan a pound, crucian carp 16 yuan a pound." On the morning of June 9, the owner of the Guangming Road Vegetable Market Aquatic Products Area near the Niuwang Temple introduced the price of various fish, sunfish 25 yuan a catty, today no, tomorrow should have. "It's still not cheap." A woman next to me who bought fish wondered, what is a sunfish and how to get it to eat? "Braised and steamed, compared to sea bass is still worse, the meat is not so fine." The owner of the fish seller said that the sunfish may be called because of its flat, shaped like the sun.
Subsequently, the reporter visited 4 vegetable markets, and the fish seller of one of the vegetable markets said that there are sunfish for sale, but they need to be booked, and the price is about 20 yuan a catty, which is changing at any time. The owners of the other three wet markets who sold fish said they did not sell sunfish. Some fish sellers said that she had been selling for more than ten years and had only seen sunfish once or twice. In addition, on the fresh online shopping platform, the reporter entered "sunfish", showing that there are more than ten merchants for sale, with prices ranging from 21.75 yuan 350 grams, 52.5 yuan 500 to 600 grams, 88 yuan and 500 grams. The reporter called the merchants one by one, and almost all the merchants said that they were not currently selling.
For the price of sunfish 25 yuan a catty, some anglers said that the price of sunfish may be because of slow growth. Crucian carp and carp can grow to half a kilogram in less than a year, and sunfish take several years. The largest he has ever seen is 7 or 8, commonly known as the slap sunfish. At the same time, there are very few small spines on the sunfish, like sea fish, commonly known as "garlic cloves", braised and steamed are delicious. Therefore, the general high-end restaurant has sunfish for sale, and ordinary restaurants may not be able to eat.
Sunfish are freshwater fish native to freshwater waters in the southern United States and northern Mexico. As the name suggests, most sunfish have an exceptionally prominent color. After entering the natural waters and hybridizing, its color gradually fades, resembling crucian carp. The spiny fin on the back is a clear sign of it. It is gluttonous and fierce, and can survive at water temperatures from 1 °C to 38 °C. Even if the surface of Sichuan's natural waters is frozen, the water temperature under it is above zero degrees, which is more suitable for sunfish to survive in terms of temperature.
How did the sunfish, native to the Americas, appear in Chinese waters? The relevant person in charge of the Sichuan Provincial Fisheries Bureau said that at present, the disorderly release of folk is the main way for the invasion of alien species, and artificial breeding "sneaking away" is also one of the sources. At present, in natural waters, whether it is official breeding and stocking, or private release, there are strict restrictions. In the event of accidents such as floods, captive alien species may also "sneak away" into natural waters. In addition to adults, such as fish eggs, it is also easy to follow the current into the natural waters.
There is precedent for the introduction of alien species for artificial culture for consumption
Sounds like sunfish seems to be a delicacy, so is it feasible for netizens to prevent their flooding by eating them? "Just relying on everyone to fish and eat, the amount is too small, it is definitely not enough." The staff of the Fisheries Research Institute of the Sichuan Academy of Agricultural Sciences said that it is currently in the Yangtze River fishing ban and the annual fixed fishing ban period, and productive fishing cannot be carried out. In addition, even in areas outside the prohibited fishing range, it is difficult to prevent the flood of sunfish by fishing. The simplest question is who can guarantee that all the sunfish will be caught.
"Sunfish grow slowly, not big enough no one eats, but when it does not grow to the size that people want, it can already endanger other fish, swallowing fish eggs, seedlings, etc." Some anglers said.
In fact, there have been artificially raised sunfish in China before. Sunfish were introduced into China's inland aquaculture in 1987, and large-scale aquaculture has been achieved in Guangdong, Fujian, Zhejiang and other places, and Sichuan has not yet. "It may be because sichuan has a lower water temperature, slower sunfish growth and relatively low economy compared to the above-mentioned areas." The staff of the Fisheries Research Institute of the Sichuan Academy of Agricultural Sciences said that the barracuda that everyone shouted was actually an exotic species. Its scientific name is spotted forktail catfish, native to the North American continent, which was later introduced into the country and cultivated for consumption. Everyone may eat artificially, so eating and preventing its flooding has little to do with it.
Focus on monitoring and evaluation, strict management
Artificial culture to prevent flooding
Eating is not the solution to the problem, so how to prevent the flood of sunfish? "Although there are many exotic species, there are not many people who have truly achieved 'anti-customer-oriented' and become dominant populations." The relevant person in charge of the Sichuan Provincial Fisheries Bureau explained that the dominant population means that this alien species not only invades, but also naturally breeds to form a certain scale, and threatens the survival of indigenous fish. It is not necessary to eat other fish directly, but also to encroach on living space, grab bait, swallow fish eggs, etc., which will affect the survival of other fish. In the natural waters of Sichuan, no such alien fish species have yet appeared.
However, although it does not really pose a threat, it should not be taken lightly. The person in charge said that since January 1, 2021, China has entered the Yangtze River ten-year fishing ban period, Sichuan many water systems belong to the Yangtze River ten-year fishing ban range, for indigenous fish and alien species, are a good opportunity to recuperate, there are also certain risks, need to pay attention to. Therefore, their work will also focus on monitoring and assessment, monitoring the growth status of various aquatic organisms and keeping abreast of changes in similar alien species in waters.
At the same time, the relevant staff of the Fisheries Research Institute of the Sichuan Academy of Agricultural Sciences said that the relevant science popularization and strict management of artificially cultivated alien species are also very important. At present, there are more and more private release activities, although the amount of individual release may not be much, but the scope is widely dispersed. Reducing the artificial release of alien species through science popularization can reduce the risk of invasive alien species. At the same time, artificial breeding is the opposite, the amount is larger and more concentrated, and it is necessary to strictly comply with relevant regulations to ensure that artificially farmed alien species will not enter natural waters.
Chengdu Business Daily - Red Star News reporter Lin Cong
Image courtesy of respondents