#头条创作挑战赛 #
Knowing that it is not easy to engage in aquaculture, we seek the prosperity of the aquatic industry. No misleading, no exaggeration, no hype, no headline party. In the context of a farmer, let you enjoy a fine product in a short time!
The Regulations on the Management of Aquatic Organism Proliferation and Discharge issued by the Ministry of Agriculture and Rural Affairs clearly stipulate that the use of alien species, hybrids, transgenic species and other aquatic biological species that do not meet ecological requirements for proliferation and release is prohibited. According to the requirements of this regulation, only native species are suitable for proliferation and release, and other species such as improved varieties (including varieties obtained by selective breeding, hybridization and other technical means), alien species and other species that do not meet ecological requirements are not suitable for proliferation and release. In principle, the release of species across water systems should not be supported, especially species with more local varieties such as carp and crucian carp, and only indigenous species in the original waters can be released.
Alien species include: foreign alien species and domestic alien species in different regions
Alien species refer to species that are not naturally distributed in a certain area or ecosystem and are directly or indirectly introduced due to human activities, of which those from international communities are called foreign alien species, and those from different watersheds or areas of the same country are called regional alien species. The counterpart to the alien species is indigenous or native species. The main hazards of alien species are affecting agricultural and fishery production, competition and exclusion of native species, reduction of biodiversity, ecological imbalance or disease, harm to other organisms and humans, etc. Unscientific release and random discarding may cause large-scale invasion of alien aquatic species, which will have a serious impact on the fragile ecological environment of the mainland's natural waters, thereby threatening national food security, ecological security and people's health. According to the Biosecurity Law of the People's Republic of China and the Measures for the Management of Invasive Alien Species, it is illegal to release alien species without permission.
Common foreign alien species and their harms
According to incomplete statistics, in order to meet the needs of aquaculture production and economic development, since the introduction of Mozambique tilapia in 1957, the mainland has introduced about 150 species of alien aquatic species from abroad. In addition, with the development of recreational and ornamental fisheries, more than 500 species of ornamental fish from abroad are known to be introduced to the country in large quantities. At present, the ornamental fish farmed in China are all foreign exotic species except for a very small number of native ornamental fish. Once these alien species enter the aquatic ecosystems of the continent, they may have serious impacts and harm to the aquatic biodiversity of the continent. At present, common alien aquatic species on the mainland include: red-eared painted turtle, American bullfrog, leather-bearded catfish, short-capped giant fat carp, Knott's butto-spotted fat carp, Protocrayfish, Fushou snail, scavenger, tilapia, gar eel, mosquito fish, lusta rova, mirror carp, snapping turtle, phoenix-eyed lily, low-eyed toothless fish, cloud-spotted pointed pond snakehead, rainbow trout, largemouth black bass, eye-spotted totoaba, spotted forktail catfish, spoonnose sturgeon, hybrid sturgeon, sunfish and so on.
1. Red-eared painted turtle (red-eared turtle, Brazilian turtle).
Native to North America, it was introduced to the continent as an ornamental turtle. Due to its strong adaptability and wide diet, once it flows into rivers, it will prey on a large number of eggs and tadpoles of small fish, shellfish and frogs, plundering the living resources of other organisms, especially native turtles, and adversely affecting their survival. At the same time, red-eared painted turtles are also vectors of disease transmission, affecting human health and aquatic animal survival. Because of its low price, it is often bought by unsuspecting people and released. In June 2015, nearly 10,000 Brazilian turtles were released from the Minjiang River by Fuzhou citizens, and local fisheries law enforcement authorities had to organize fishing boats to hunt down Brazilian turtles.
Figure 1: Red-eared painted turtle (Trachemys scripta elegans)
2. American bullfrog (American frog).
Native to the east of the Rocky Mountains of North America, the bullfrog is a large food frog that was introduced to the mainland in 1959. Due to its strong adaptability, wide diet, few natural enemies, long life expectancy and strong reproductive ability, it has obvious competitive advantages and is easy to invade and spread, thus threatening the survival of native aquatic organisms. In addition, the chytrid fungus it carries is an important cause of the extinction of amphibians.
Figure 2. American bullfrog (Rana catesbeiana)
3. Leather-bearded catfish (Egyptian pond lice).
Introduced from Egypt in November 1981, the bearded catfish is similar in morphology to that found in the southern part of the mainland. Due to their large size, fast growth, easy reproduction, strong adaptability, low oxygen tolerance and low temperature resistance, dominant species are easily formed in natural waters, and can pose a threat to local aquatic organisms through predation and competition.
Figure 3. Bearded catfish (Clarias lazera)
4. Short-capped fatty carp (freshwater white pomfrey).
Native to the Amazon basin, it resembles the man-eating pomfret (Knott's buttocks), but has a small mouth cleft. Freshwater pomfret is found in natural water bodies in southern China, and can threaten the survival of other organisms and destroy biodiversity through predation and food competition. This species has high water temperature requirements, begins to die when it is below 7 °C, and cannot overwinter in the natural water body in the north.
Figure 4. Piaractus brachypomus
5. Knott's rump carp (piranhas, man-eating pomfrets).
Native to the Brazilian Amazon basin, it is similar in appearance to the freshwater pomfret with distinct protruding jaws and larger mouth fissures. Man-eating pomfret is aggressive to humans and is a typical high-risk alien fish. In recent years, reports of piranhas found in Guangxi and even many rivers in China have appeared in the news, but after identification, they are basically short-capped fat carp. Unlike freshwater pomfrets, man-eating pomfret are very cold-sensitive and die below 20°C in water temperature, considering that winter temperatures can reach below 20°C even in tropical monsoon climate zones on the mainland, and it is unlikely that man-eating pomfrets will overwinter in domestic natural waters.
Figure 5. Pygocentrus nattereri
6. Protocrayfish cruzi (crayfish).
Native to North America, it has strong stress resistance, fast reproduction speed, can survive in various water bodies, and is an excellent breeding species. Protocrayfish cruzi likes to dwell in caves and is good at burrowing, which will lead to the loss of irrigation water in some terraced areas, which has caused certain harm in some areas of Guizhou and Yunnan.
Figure 6. Procambarus clarkii
7. Fushou snail (apple snail).
Native to the Amazon River Basin, it was introduced to the mainland as a special economic animal for breeding in the 80s of last century, but it was abandoned and flooded in most parts of the country due to its poor taste and carrying zoonotic parasites. The large amount of food of Fushou snails can cause the yield of rice and other aquatic plants to decrease or even lose the harvest, seriously affecting food production.
Figure 7. Pomacea canaliculata
8. Scavengers (catfish, sucker fish, anglerfish).
In fact, it may include many species such as wild winged catfish and leopard winged catfish. Native to the Amazon basin, it was introduced as an "aquatic cleaner" in tropical fish farming. Scavengers have few natural enemies and strong fecundity, not only scraping algae, but also devouring fish eggs and fry, seriously threatening the reproduction and growth of other fish. At present, it has been found in some rivers south of the Yangtze River, and the fish has adversely affected the ecology of some waters in the Pearl River Basin.
Figure 8.1 Pterygoplichthys disjunctivus
Figure 8.2 Pterygoplichthys pardalis
9. Tilapia (African crucian carp).
It includes several species of the genus Tilapia, Broomtooth Tilapia and Crucian Crucian Cyprian, with the continent most commonly including Nile tilapia, Tilapia Zi, Olea Olea, Galileo Tilapia, Mozambique Tilapia and cross-bred varieties. Native to Africa and the Middle East, like high temperature, low oxygen tolerance, sea and fresh water can live, omnivorous, strong food grabbing, rapid growth, has been widely introduced by other countries and regions, is the United Nations recommended for breeding high-quality aquaculture species. The negative impact of tilapia on the ecological environment is mainly due to its rapid reproduction rate and large population size, resulting in too single fish species in the water, crowding out the living space of other fish species, and breaking the original ecological balance. In parts of the southern waters, tilapia has become the dominant species.
Figure 9.1 Nile tilapia (Oreochromis niloticus)
Figure 9.2 Tilapia zillii
Figure 9.3 Oreochromis aureus
Figure 9.4 Galileo tilapia (Sarotherodon galilaeus)
Figure 9.5 Mozambican tilapia (Oreochromis mossambicus)
10. Damselfish.
Native to the Americas, including 7 species such as eye-spotted gar eel, alligator eel, and gharial gar eel, the more common are alligator eels and eye-spotted gar eels introduced in the mainland, and the most common in natural waters is alligator eels. Due to its ferocious nature and high viability, alligator eels will cause unpredictable harm to fisheries production and aquatic ecosystems if they survive in new environments in the form of invasive alien species. It should be noted that the fish eggs are highly toxic and the meat is edible but slightly difficult to process. At present, alligator eels have been found in inland rivers and park lakes in some cities across the country, and most of them have been investigated because citizens are reluctant to discard or release them after breeding.
Figure 10.1 Alligator eel (Atractosteus spatula)
Figure 10.2 Lepisosteus oculatus
11. Mosquito fish (wicker, potbelly).
It is native to Central and North America. Because it has a certain effect on the eradication of Anopheles mosquitoes and other mosquito larvae, pollution resistance, strong adaptability, high reproductive ability, it has been introduced to all over the world for mosquito control. Because it competes with native fish from all over the world and disrupts the ecological balance, it is listed by the International Union for Conservation of Nature as one of the world's top 100 invasive species. In the human activity area of South China, mosquito fish have replaced local killifish through competition, and even affected the survival of local amphibians such as frogs and salamanders.
Figure 11 Mosquito fish (Gambusia affinis)
12. Meragarai (Bengal carva, red-eyed carva, wheat mackerel, Indian carpout).
Native to South Asia, it was introduced to the mainland as a cultured species, growing rapidly, with large individuals, and is currently mainly used as a feed fish for carnivorous fish. It is more common in the Pearl River and Yangtze River systems, and poses a greater threat to native species such as the mackerel.
Figure 12 Cirrhinus mrigala
13. Rusta roon (South Asian rounder, Thai rounder).
Native to South Asia, it is commonly farmed in the southern regions of the continent. Once it enters natural waters, it is easy to seize the ecological resources of local indigenous fish species and crowd out the living space of other species.
Figure 13 Rusta rohita
14. Mirror carp.
Native to Europe, including German mirror carp, loose scale mirror carp, Ukrainian scale carp and other hybrid improved varieties, it has been promoted and cultured in Northeast, North China, Northwest China and other places. Access to natural waters may occupy the ecological niche of native carp and cause genetic erosion of native carp.
Figure 14 Cyprinus carpio var. specularis）
15. Cloud-spotted pointed pond snakehead (bamboo shell fish).
Native to Southeast Asia, it was introduced as a cultured species. It is currently distributed in Hainan Island and parts of Guangdong. It is a ferocious predator and is more harmful to fish fry and shrimp fry in cultured waters. In natural waters, it can also affect the survival of native species.
Figure 15 Oxyeleotris marmorata
16. Managuali (Flower-bodied cichlid).
Native to Central America, also known as freshwater grouper, flower tiger, and beautiful tilapia, it was first introduced to the mainland as a farmed species. It is widely distributed in Hainan Island, with strong feeding capacity and environmental adaptability, and poses a greater threat to native species.
Figure 16 Managuali fish (Parachromis managuensis)
17. Texas leopard (Texas fish, Hulk).
Native to North America, it was originally introduced to the mainland as an ornamental fish. It is a carnivorous ferocious fish with a strong physique, strong sense of territory, and easy to attack and devour other small fish. At present, it has been repeatedly found in the Pearl River Basin and Hainan Island.
Figure 17 Herichthys carpintis
18. Threaded snakehead (Thai snakehead).
It is native to Southeast Asian countries. Due to its characteristics of low oxygen resistance, strong fouling resistance, fast growth, easy escape, and child protection, its salinity tolerance is stronger than that of spotted snakehead, resulting in its easy diffusion in natural waters. Natural populations have been found in some water systems in the Pearl River Basin.
Figure 18 Channa striata
19. Brachycephalus (Bulbophyllum grandeum).
Native to the Caspian region of Central Asia, it was introduced to the mainland in 2003 and successfully bred artificially, and has been cultured in many places. It has the characteristics of wide temperature resistance, low temperature resistance, low oxygen resistance, salinity resistance, etc., and is easy to survive in natural waters. The main hazard of its invasion is competition with indigenous fish for food and habitat, especially in saline waters, which have been recorded in some natural waters of the Yellow, Yangtze and Pearl River basins.
Figure 19 Luciobarbus brachycephalus
20. Snapping turtles.
Native to Central and North America, it includes both large snapping turtles (true snapping turtles) and small snapping turtles (quasi-snapping turtles). It has been introduced as an ornamental and food animal and is now raised in most parts of the mainland. It grows rapidly, is fierce by nature, and is very aggressive. Due to the lack of natural enemies, once released into the wild, it will pose a serious threat to local aquatic animals and cause great harm to the ecological environment.
Figure 20.1 Small snapping turtle (Chelydra serpentina)
Figure 20.2 Macrochelys temminckii
21. Florida turtle (American mountain turtle, pearl turtle).
Native to the United States, it has been introduced to the mainland to carry out aquaculture in many places. Due to breeding escape and random release, coupled with its strong environmental adaptability and fecundity, there have been continuous reports of capture in various places in recent years. In the natural water body, it may occupy the ecology of native turtles and prey on other aquatic organisms, which will adversely affect the ecological environment of the water.
Figure 21 Florida turtle (Apaloneferox)
22. Phoenix lily (water hyacinth).
Native to South America, it was promoted as pig feed in the 50s and has now grown as a weed in the Yangtze River basin and southern regions. The reproductive ability is very strong, once there is an environment suitable for its growth, it will grow rapidly and become the dominant species in the local area, inhibiting or affecting the growth of other species, destroying ecological diversity, and easily causing ecological deterioration in the area.
Figure 22 Eichhornia crassipes
23. Striped carp (Brazilian sea bream, small-mouthed carp).
Native to the Paraná and Paraguay rivers in southern Brazil, it was introduced to the mainland as a food fish by the Zhejiang Freshwater and Fisheries Research Institute in 1996 and successfully bred in 1998. It has the characteristics of strong adaptability to the environment, food miscellaneous, low oxygen resistance, low temperature resistance, etc., so there is a certain risk of invasion in the natural waters of the southern part of the mainland, and there are currently population distribution in some rivers and reservoirs such as Guangdong and Guangxi, and there are more in the lower flow speed of the river. The main hazard is competition for food and space with native indigenous fish.
Figure 23 Prochilodus lineatus
24. Rainbow trout.
Native to North America. Carnivorous fish, fierce sex, listed by the IUCN as the world's top 100 invasive species. It was introduced to the country as a food fish and is now farmed in most parts of the country. Due to its predatory nature, it may occupy the ecological niche of native salmonids, but also prey on other fish, resulting in the decline of other fish populations, which have been found many times in the upper reaches of the Yellow River.
Figure 24 Rainbow trout (Oncorhynchus mykiss)
25. Largemouth bass (California bass).
Native to North America. In the 80s, the mainland was introduced from abroad and achieved successful artificial breeding, and the current aquaculture capacity in central and southern China is relatively large. Typical carnivorous fish, strong predator, large food intake, like to prey on small fish and shrimp. It grows rapidly, and the maximum weight obtained by fishing in rivers is more than 10 kg. Once in natural waters, largemouth bass can swallow fertilized eggs and juveniles of other fish, inhibiting the population growth of other fish, which can have serious consequences.
Figure 25 Largemouth bass (Micropterus salmoides)
26. Eye-spotted totoaba (American redfish).
It is native to the waters of the South Atlantic and Gulf Coast. It grows rapidly, has strong adaptability to the external environment, is a wide temperature and wide salt fish, has a wide range of diet, and does not have high requirements for bait. The mainland began to introduce and breed in 1991, and the range of culture has been expanding from south to north. Due to the escape and random release during the breeding process, in recent years it has been caught in some places along the beach, rocky reef, breakwater, etc., and in 2010, an American redfish weighing 26 kg was caught on Xiangshan Yushan Island. Because of its high viability and prey on native fish, it may adversely affect marine ecology.
Figure 26 Sciaenops ocellatus
27. Spotted forktail catfish (Trench catfish).
Native to North America. In the 80s, the mainland was introduced from abroad and achieved success in breeding and breeding, and at present, aquaculture is available in most parts of the country, and artificial breeding has formed a relatively large scale. Resistant to low oxygen, wide adaptability to the pH and salinity of water bodies, carnivorous. Due to its wide range of adaptations, once it enters natural waters and establishes a population, it may occupy the ecological niche of native fish such as catfish, causing the decline of other fish stocks.
Figure 27 Spotted forktail catfish (Ictalurus punetaus)
28. Spoon sturgeon (platypus).
It is native to the Mississippi River in the United States. Wide temperature range, filter feeding, fast growth rate. Introduced in 1988, it has successfully cultivated artificial seedlings and promoted breeding in more than 20 provinces, autonomous regions and cities across the country. Due to the escape of the breeding process and the random release, in recent years, rivers and lakes in Jiangsu, Zhejiang, Hubei, Shaanxi, Anhui and other places have been repeatedly caught.
Figure 28 Spoon sturgeon (Polyodon spathula)
29. Hybrid sturgeon.
Including the hybrid offspring of a variety of sturgeon, the common ones are small miscellaneous (with small body sturgeon as the father, Dar's fish as the mother), Xizai (with the Siberian sturgeon as the father, Shi's sturgeon as the mother), and Tai Miscellaneous (with the sturgeon as the father, the Dar's fish as the mother). It has a fast growth rate and strong disease resistance, and it is farmed in most parts of the country. Due to the escape and random release of animals during the breeding process, rivers, reservoirs and lakes have been found in Ningxia, Sichuan, Zhejiang, Qingdao, Shaanxi, Hubei and other places in recent years.
Figure 29.1 Hybrid sturgeon (small hybrid) (Huso huso×Acipenser ruthenus)
Figure 29.2 Hybrid sturgeon (Acipenser baerii×Acipenser schrencki)
Figure 29.3 Hybrid sturgeon (Huso huso×Acipenser schrencki)
30. Sunfish.
Including bluegill sunfish, green sunfish and other sunfish species and their hybrid offspring, the mainland was introduced from the United States in 1987, and has been cultured in Guangdong, Guangxi, Hunan, Hubei and Zhejiang. This species is suitable for breeding and culture in lakes, reservoirs and ponds, and is an ideal object for freshwater aquaculture and ornamental fish culture. The fish is extremely invasive and destructive, and has been repeatedly found in many rivers in recent years. Bluegill sunfish have been caught many times in the Qiantang River system, and in 2015, a large wild group of green sunfish was found in the Weihe River Basin in the Dabie Mountains.
Figure 30.1 Bluegill sunfish (Lepomis macrochirus)
Figure 30.2 Green sunfish (Lepomis cyanellus)
Alien species and their hazards in different regions of the country
In addition to foreign alien species, alien species introduced between different watersheds and water systems belong to regional alien species. For the needs of aquaculture production and economic development, many species with excellent production traits in the mainland have been transplanted or introduced into other non-situ areas. For example, the group head bream is native to the Tongjiang Lake in the middle and lower reaches of the Yangtze River, a species that inhabits still water, and has been introduced to many provinces and cities across the country for aquaculture, and even in rivers to carry out breeding and release. Originally only found in the Irtysh River basin in Xinjiang, they have been transplanted to many provinces and cities outside Xinjiang for cultivation, and have been found many times in natural water bodies.
Figure 31 Megalobrama amblycephala
Figure 32 Tinca tinca
Figure 33 Barruda (Sander lucioperca)
The impact of alien species on the ecological environment in different regions of China is also prominent. Native fish species in the southern part of the continent, such as the "four big fish" (blue carp, grass carp, silver carp, bighead) were introduced into the high-altitude waters of the northwest and southwest, and the disasters caused by these species and the small trash fish (goby, wheat earfish, etc.) brought in with the introduction of these species are no less than those caused by foreign species. The cultivation of bighead in Qilu Lake and Xingyun Lake in Yunnan Province has led to a sharp decline in the local bighead carp population, and now it has to rely on artificial cultivation. At the end of the 70s, in order to promote economic development, whitebait was introduced into Dianchi Lake, and for a few years, whitebait became an absolutely dominant species in Dianchi Lake, but the indigenous fish of Dianchi Lake were destroyed. River bass introduced from the Irtysh River once led to the extinction of Xinjiang bighead fish in Xinjiang's Bosten Lake.
Figure 34 Aristichthys nobilis
Figure 35 Perca fluviatilis
In addition, since most of the fish and amphibians and reptiles in the inland waters of the mainland have geographical populations (that is, there is obvious genetic differentiation in geography), the parents of the released species should come from the origin of the released waters, that is, the principle of "where to come and where to release", and the released geographical populations should not be mixed. River crabs have formed different populations such as the Yangtze River, Liaohe River, Oujiang River and Min River through long-term evolution in different water systems of the mainland, with different morphological phenotypes and characteristics, which is the result of long-term natural selection and evolution. However, in the past 20 years, river crab culture has developed rapidly in the mainland, and due to the northern transport of seedlings and blind transplantation, it has caused germplasm mixing and trait decline between different water systems of river crabs.
Figure 36 Chinese river crab (Eriocheir sinensis)
Genomic-level research data reveal that the Chinese giant salamander consists of at least 5 species, and it is speculated that there may be as many as 8 species, which are closely related to the distribution of water systems, roughly corresponding to the Yellow River, Yangtze River, Pearl River and Qiantang River basin. For the current proliferation and release, some experts suggest strengthening genetic screening, paying special attention to the distribution of different species in the corresponding watershed, avoiding population decline caused by distant hybridization, and prohibiting disorderly exile without genetic verification.
Figure 37 Potential genetic unit of the giant salamander (Andrias davidianus) (cited in Yan et al., 2018)
(Source: Chinese Fisheries Society Scientific Fish Popularization Expert Team)
(Southwest Fishing Network slightly adjusted)
Related Articles:
Book: 120 species of regional economic species of the main freshwater fish allowed by continental stocking and stocking
Book: 21 species of major freshwater fish allowed by continental stocking and stocking
Book: Major rare and endangered species allowed by continental stocking and release
126 hybrid species of exotic species prohibited from release were selected and bred in the mainland, and various suitable species for release were evaluated
Fishery practitioners, seek a prosperous fishery! Please pay attention to the headline number @ Fisherman Liu Wenjun, for more wonderful content, please log in to the Southwest Fishery Network and the first line of fish farming public account, if you want to reprint the original of this article, please indicate the source, if you have different opinions or content supplements, please send a private message or leave a message or comment to share! #Variety##Aquatic Products##Chinese Authentic Customs##我想对你说 #