A large number of sunfish were found in many places in Sichuan, and sunfish "invaded". It has to be said that there have been so many illegal entry incidents of alien species recently, including the interception of 19 salamanders by Beijing Customs; Xiamen intercepted five living halberds and so on. People's awareness of prevention has indeed risen, knowing how serious the consequences of these alien species will be to China's ecological environment.
A large number of sunfish were found in many places in Sichuan, and sunfish "invaded"? 1 recently, when fishing in a reservoir in Chengdu, a fisherman caught a large number of sunfish, and they were all very big. This fisherman is rich in knowledge, and he is worried that such a large number of fish native to North America will cause species invasion and devour the living environment of local fish.
This stone has aroused thousands of waves, and fishermen from all over Chengdu have also responded, saying that they have caught sunfish in major reservoirs!
I have to say that I have experienced so many illegal entry incidents of alien species recently, including the interception of 19 salamanders by Beijing Customs; Xiamen intercepted five living halberds and so on. People's awareness of prevention has indeed risen, knowing how serious the consequences of these alien species will be to China's ecological environment.
Fortunately, after the intervention of relevant departments, it was found that the number of sunfish in Chengdu is not huge at present, and it will not be flooded for the time being. Moreover, during the fishing ban in the next decade, relevant departments will increase the prevention and control of exotic aquatic species.
What kind of fish is sunfish?
Sunfish originated in America and is an important and abundant fish in America. They are one of the most common species in Ohio and can be found in almost every water area in the state. They are most abundant in clear lakes and ponds with some deep-rooted aquatic plants.
Sunfish is actually a general term, and all kinds of sunfish often cross each other. Although all kinds of sunfish are not the main fish in the United States, if they are counted as sunfish, they constitute the bulk of fish in each stream. Fishing friends in these areas are really boring. Seven of the fishing 10 are sunfish.
They are extremely picky eaters, and zooplankton, insects and other invertebrates can all be used as food.
If you go fishing for sunfish in late spring or early summer, you will be big, and this is the period in China.
Harmful point of sunfish
Sunfish usually move in groups. They lay eggs many times between May and August. But their reproductive ability is really outrageous.
The spawning peak of sunfish usually occurs in June. The male chooses shallow water with a depth of 2.5cm to 10cm, and sweeps out a dish-shaped nest with his tail. Then females lay 10,000 to 60,000 eggs in nests guarded by males.
These eggs usually hatch in about five days. Newborn sunfish cubs don't need to be taken care of, and they can thrive by eating plankton themselves.
These data are a bit shocking. Such a strong reproductive ability will inevitably cause great damage to local scarce species, and then affect the ecosystem. Most species invade living things, which is the most frightening thing.
Japan is a bloody lesson. 1 964, a fishery research institute in Japan introduced 1400 sunfish, trying to treat them as common table delicacies in Japan. As a result, they underestimated the reproductive ability of sunfish. In just over 30 years, sunfish have spread all over almost all rivers and lakes in Japan.
They are raging wildly, driving all kinds of precious fish in Japan to near extinction! The main reason is that the Japanese who have a good life are too comfortable. It was not until 2000 that they realized the seriousness of the problem.
Is sunfish delicious?
Sunfish not only looks like tilapia, but also tastes a bit like it. Sunfish has delicate meat, hard bones, but not much. The fish soup is very delicious, and it is easy to boil white soup. It can be said that it is a big star in the aquatic product market.
Its price is relatively stable, generally 18-22 yuan/kg, and it is well received by diners.
A large number of sunfish were found in many places in Sichuan, and sunfish "invaded"? 2 What are the hazards of biological invasion?
1, economic loss
In China, from south to north and from east to west, the troubles caused by these alien invaders can be seen almost everywhere. "China is one of the countries suffering the most from alien species invasion.
From 200/kloc-0 to 2003, the former state environmental protection administration organized a national survey of alien invasive species. According to the investigation, there are 283 alien invasive species in China, which cause economic and environmental losses of about120 billion yuan every year, but now the losses have reached 200 billion yuan.
According to the report of the International Union for Conservation of Natural Resources (IUCN), the economic losses caused by the invasion of alien species to the world exceed 400 billion US dollars every year. Worryingly, 46.3% of these alien invasive species have invaded nature reserves.
Jesson Wang, director of the Biosafety Management Division of the Natural Ecology Protection Department of the Ministry of Environmental Protection, said recently. Environmental experts believe that in recent years, the phenomenon of alien biological invasion in China is increasing day by day, and the resulting biological safety problems are becoming more and more serious, so it is urgent to effectively prevent the invasion of alien species.
2, species extinction
After alien pests invade new areas suitable for growth, their populations will multiply rapidly and gradually develop into new local "dominant species", which will seriously damage the local ecological security.
Specifically, the negative consequences mainly include the following: First, the invasion of alien species will seriously destroy the biodiversity of organisms and accelerate the extinction of species. Biological diversity is a complex system with different levels, including all plants, animals, microbial species and their genetic information, organisms and living environment.
Although the biodiversity of a country or a region is endowed by nature, any country must invest a lot of manpower and material resources to try its best to maintain its biodiversity.
However, the invasion of alien species is the number one enemy that threatens biodiversity. After the invasive species are introduced to different places, due to the lack of natural enemies and other restrictive factors that can restrict their reproduction, the consequences are rapid spread, massive expansion, formation of dominant species, and competition with local species for limited food and space resources, which directly leads to the degradation and even extinction of local species.
3. Destroy the ecology
The invasion of alien species will affect the water and other nutrients in plant soil, as well as the structural stability and genetic diversity of biological communities, thus destroying the local ecological balance.
For example, Mikania micrantha, an exotic species introduced from Australia and invaded many forest farms in China Hainan Island and Leizhou Peninsula, is extremely dry because it can absorb a lot of soil moisture, which is very unfavorable to soil and water conservation. In addition, Mikania micrantha can secrete chemicals to inhibit the growth of other plants, which once seriously affected the production and development of the whole forest farm.
4, threatening health
For example, "dutch elm disease", which originated in East Asia, invaded Europe and caused elm death in most European countries twice in 19 10 and 1970. Another example is ragweed introduced to China 40 years ago. The hay fever caused by its pollen will do great harm to human health.
Every July to September when pollen drifts, people with physical allergies will have asthma, sneezing, runny nose and other symptoms, and even die due to other complications.