The "top freshwater fish killer", which has existed 100 million years, has recently made waves in China ...

Author:Look at the think tank Time:2022.08.30

Recently, Yunzen Lake, Central Park, Ruzhou City, Pingdingshan, Henan Province, has attracted much attention. Some live broadcast shows that online onlookers exceeded 30 million.

After nearly a month of pumping, 300,000 cubic meters of lake water was basically dry. At about 00:00 on August 27, the truth finally surfaced: one, one small and two "strange fish" identities were confirmed, and they were crocodiles that had more than 100 million years on the earth.

Captive crocodile. Picture source: Ruzhou Central Park

How powerful is the crocodile crook, known as the "top freshwater fish killer"?

As a unique species in North America, how can it come to China not far away? What impact did us bring us?

Text | Xie Fang Watch Think Tank Observer

This article is comprehensive by the Observatory Think Tank.

Two Dan Dan Ge's fishing operations

After the appearance of "strange fish", the managers of the Central Park of Ruzhou initially tried to fish with a large -scale net. Later, they invited a professional fishing team to use sonar positioning to find "strange fish". However, crocodile crickets may lurk due to disturbance. Subsequently, the park purchased large fences and trapped bait, and still found nothing.

The lake of Yunchen Lake is very wide and the water depths are different. The deepest part is seven or eight meters, and there is a U -shaped pipeline in the middle. It is speculated that it is hidden here after being shocked. The U -shaped pipeline has poor light, insufficient oxygen, and silt, water plants, etc., which is very difficult to fish.

In the end, the garden decided to drain the lake.

Picture source: "News 1+1"

In the early stage, the staff of the garden party carried out water body salvation and drainage, and the cost was not very high. After dried water, it is necessary to capture crocodiles in the U -shaped pipeline. There is a certain difficulty in the original class. As a result, a volunteer rescue team of nearly 20 people joined it.

At about 00:00 on August 27, one, one small, and two crocodiles were arrested. The large body was about 90 cm in length, about 25 catties of weight, the small body was about 70 cm in length, and the weight was more than a dozen pounds. The arrest team said, "When we pump the water almost, we will be captured by the depth of more than 100 meters of the pipeline. At that time, the water level was less than one meter."

At present, the managers of Ruzhou City Park have been harmless to it and arranged personnel to disinfect the lake area.

Not only the Central Park of Ruzhou. In the Spring Festival in 2019, Guangzhou Baiyun Lake Park has also captured crocodile.

On February 9th of that year, the staff of Baiyun Lake Park found a "strange fish" during the patrol, which was huge in size and occasionally floated. A small part of the body was exposed to the surface.

On the 13th, the fishing operation entered the implementation stage. It adopted a scheme mainly based on the "enclosure+dragging method" and supplemented by the "throwing method". At the same time, the Baiyun Lake Management Office should try to reduce the water level in the lake through the pumping station, so that the large waters of the western lake area expose the beach.

On the 15th, the fishing group completed the siege of the 300 acres of waters, starting from 10 o'clock that night, and investigated one by one from 25,000 kilograms of fish overnight. The crocodile crickets.

However, after comparison, the fish found that the fish caught in the fishing group did not match the shape of the "strange fish" when inspected by the staff, and continued to implement the fence. Eventually, a "bend over 1.2 meters long and up to 10 kg of" bend over Bow back "crocodile bird.

The two fish were brought back to the Pearl River Aquatic Research Institute for anatomy and analyzing the sample data to analyze Baiyun Lake fish ecological population structure.

"Strange Fish" frequently appear, all of which are crocodile

In recent months, reports on crocodile crickets have appeared in Beijing, Hunan, Guangxi, Jiangsu, Qinghai, Ningxia, Yunnan, and Shandong.

At the end of July, the residents of the Baiwang Jasmine Park Community in Haidian District, Beijing, saw a "crocodile" more than a half meters long in the water system in the community. Since then, some owners recognize that they are crocodiles, and one of the old gentlemen squatted for several days in a row, and eventually picked it up and handed it over to the property.

Many owners say that people often see people release in the community, usually goldfish, bullfrogs, turtles, etc., but I do not expect that there will be crocodile crickets. Li Li, the webmaster of a wild animal protection station in Beijing, said that the most released is fish such as crocodile crickets, and some Brazilian turtles and crocodile turtles are crawled.

On August 17, the crocodile crickets in the landscape pool in Jingjiang City, Jiangsu, bite a boy's finger. The boy's parents said, "The child's wound was bleeding at the time, and we cleaned the inflammation for him. There were six or seven scars on it, about 1cm."

On the 25th, in the Lotus Pond in Xishan Scenic Area, Guiping City, Guangxi, two crocodile crickets (both about 1 meter long and about 7.5 kg) were successfully captured.

The crocodile crickets captured by Sichuan Zigong fishermen. Figure ｜ Vision China

On the 26th, the Citizens of the Dynamic and Plant Plant Prevention and Control Center of Changsha City, Hunan, said that a citizen was caught in a "strange fish" in Yuelu District. The long mouth was similar to the crocodile. This is also the first time that Hunan has discovered crocodile.

On the same day, a "strange fish" appeared in the landscape pool in a community in Kunming, Yunnan. The property took off 400 cubic meters of water in the pool for 3 hours and caught a crocodile cricket with a length of about 60 cm and a weight of about 3 kg.

The next day, several "strange fish" appeared in the artificial lake in a community in the west coast of Qingdao City, Shandong City. It was more than one meter long, with long mouth teeth, and eating other fish in the lake. After learning the news, the local government quickly organized community properties for pumping. At present, two crocodile birds have been caught ashore, but there are still fish leaks in the lake, and fishing is still in progress. In addition, the students of Sun Yat -sen University have also photographed crocodiles in the lake on campus.

The question is, how do they enter China?

"Top Freshwater Fish Killer"

There are no crocodile crickets in China.

At present, there are two main ways to introduce foreign fish into my country -aquaculture and watching fisheries. Gu Daen, a scientist of the National Grand Freshwater Fish Industry Technology System Invasion and Control Positions, introduced that most of the early domestic crocodiles came from illegal smuggling channels. At the beginning of this century Started artificial reproduction.

There are two reasons why they become ornamental fish: one is that the meat is rough and not delicious, and the other is the unique appearance and personality.

Crocodile Crusades are unique species of North America, also known as blessing, belonging to the genus of the crickets, the family of birds, and the big bird. They are mainly distributed in the river and river mouth waters, the Missouri and Ohio River from Mexico, the Gulf of Mexico from Mexico to Florida, USA Wait, it is one of the top ten fierce freshwater fish in the world.

They have existed on the earth for more than 100 million years. During the long evolution, the scales on their bodies became as thick as a coin, and there were enamel substances similar to human tooth surfaces, which can help them resist 90% when they encounter natural enemies. The above damage. At the same time, their mouths such as crocodiles, the protruding upper and lower jaws are full of two rows of sharp teeth, which can cause fatal damage to the prey.

The thick scales and sharp teeth are always at the top of the food chain in the five largest lake waters of the United States, so it is named "top freshwater fish killer". Their prey includes a variety of fish, crustaceans, amphibians, birds, small and medium mammals, etc., which are almost not picky.

In order to adapt to the environment, the fish -like pupae of crocodile also evolved a function similar to airbags. When hypoxia in water, they can breathe oxygen in the air directly, and they can also survive on the land by making the fish filled with the air, so they can survive on the land.

Adult crocodiles are generally 1.2 to 1.8 meters long, with a maximum of 3 meters. The body is huge and lacks natural enemies. It is extremely harmful. In addition, the reproduction ability of crocodile crickets is also very strong. It can produce tens of thousands of fish eggs each year, green, toxic.

The peculiar and fierce crocodile crooked birds have naturally aroused the desire to buy fish consumers. It is understood that at present, the breeding crocodiles are mainly concentrated in Guangdong. Due to the large amount of reproduction, the crocodile crickets are easy to buy online and offline, and the price is relatively cheap. Generally, more than ten dollars can buy a juvenile fish, which is about hundreds of dollars.

As a crocodile of ornamental fish. Figure ｜ Figure insect creativity

However, the crocodile crickets eat more and grow fast, and they can grow to more than 1 meter in a short period of time. Some owners choose to abandon them; in addition, some people buy crocodile birds to release them.

Gu Dangen said, "Most of the diffusion of crocodile criminals is still manual, and the 'strange fish' found by Ruzhou may be released in the lake after being purchased and breeding."

The manager of Ruzhou Central Park also said that it was speculated that the relevant experts were speculated that it was suspected of "artificial release".

The crocodile lack of natural enemies in China. Once entering the natural waters, it will bring a disaster to local fish communities, which seriously endangers the diversity of aquatic biological diversity and the ecological safety of the waters.

For example, after the fish in a certain waters are preyed by crocodile croaks and reduced a large amount of reduction, the algae of the fish as food will be flooded in large areas. The formation of a single species in this waters may cause hypoxia in the water body and cause a certain range within a certain range. Ecological disaster. For another example, when the food is short, crocodile can even attack humans.

Mr. Kong Kong, a staff member of the Henan Water Conservancy Investment Group, who participated in the fishing operation of Ruzhou Central Park, said that during the search process, they found that the fish in the lake had been eaten. Humanity.

Adhere to the "Biological Safety Line"

The behavior of abandonment and release of foreign species is seriously threatening the country's "biological safety defense line".

In recent years, the number of invasion of foreign species in my country has shown an upward trend and has become one of the most harmful countries in the world.

The "2020 China Ecological Environmental Status" shows that more than 660 kinds of foreign invasion species have been found in my country. Among them, 71 types have caused or have potential threats to the natural ecosystem and have been included in the "List of Chinese Foreign Invasion Species", and 219 kinds of invasion of national nature reserves.

The water gourd native to South America has a rapid reproduction and covered with water, causing a large number of aquatic creatures to die due to lack of oxygen and sunshine; pine material native native to North America, infected with pine materials (known as the pine tree "" AIDS ") died after 40 days of infection of pine trees; native to Central and North America, was introduced to control mosquito fish fish that control mosquito reproduction and malaria. Grass -galvan moths invaded in our country seriously endangered crops such as corn and other crops; and so on.

In response to the previously introduced crocodile crickets, Gu Dangen said that when "released and implemented the" State Key Management Foreign Species List (First Batch) "in 2012, there is no evidence to prove that crocodile crickets can reproduce in the wild, and the number at that time was also at that time. There are fewer. But the current data has proved that crocodile crickets can be reproduced in the wild. Customs and agricultural and rural departments have already begun to move to prevent these species from introducing them. "On April 15, 2021, my country officially implemented the" Biological Safety of the People's Republic of China. The Law (hereinafter referred to as the Biological Safety Law) stipulates the content of preventing foreign species invasion and protecting biodiversity, and requires the formulation of a list of foreign invasion species and management methods. To this end, this year, the Ministry of Agriculture and Rural Affairs and other relevant departments have formulated the "Notice on Printing and Distributing the Overall Plan of Foreign Invasive Species Census" to conduct a national census for 10 major foreign aquatic creatures, including crocodile crickets.

Ren Dapeng, a professor of Chinese Agricultural University, introduced that "foreign invasion species" and "foreign species" are two different concepts. Foreign species are not all invasive species. Whether it is an invasive species requires long -term scientific assessment. But as long as it is a foreign species, no matter whether it is included in a list, there are strict management regulations. For example, Article 60, paragraph 3 of the Biological Safety Law stipulates that any unit or individual shall not introduce, release or discard foreign species without approval.

Starting on August 1, 2022, the "Administrative Measures for Foreign Invasion Species" jointly issued by the Ministry of Agriculture and Rural Ministry, the Ministry of Natural Resources, the Ministry of Ecology and Environment, and the General Administration of Customs officially began. This is the first management method for preventing and controlling foreign species in my country.

The method is clear that the management of foreign invasion species is an important measure to maintain national biological safety. It should adhere to the principles of risk prevention, source control, comprehensive governance, collaborative cooperation, and public participation. Any unit or individual shall not introduce, release or discard foreign species without approval. If it is not approved and is introduced, released, or discarded foreign species without authorization, punishment will be punished in accordance with Article 81 of the Biological Safety Law.

Article 81 of the Biological Safety Law stipulates that without approved and unauthorized release or discard foreign species, the relevant departments of the people's governments at or above the county level shall be ordered to capture, retrieve foreign species that will be arrested, retrieved or discarded according to their responsibilities. Fined fines of more than 10,000 yuan.

Reference materials:

1. Reporting in many places found that "strange fish" | Jiang Ziwen, surging news, 2022-08-28

2. "Strange Fish" seized, two | Tian Meng, CCTV News, 2022-08-27

3. What is this "strange fish"? Expert Interpretation | CCTV News, 2022-08-26

4. Is there a "strange fish" in the ditch in the community? Originally crocodile! Bring in and release foreign species illegal | Huang Pinchao, Beijing Evening News, 2022-08-01

5. The fish and shrimp in the pond were "destroyed"! Kunming: Survey of Experts Group for Establishment | Spring City Evening News, 2022-08-28

6. How difficult is this "strange fish"? Aquatic experts shared their arrest experience in Guangzhou | Chen Liang, Yangcheng Evening News, 2022-08-28

7. Cases of foreign invasion of aquatic biological governance | Institute of Pearl River Aquatic Products Institute of China Institute of Aquatic Sciences, Ocean and Fisheries, No. 10, 2020

8. Common foreign aquatic biological introduction in the waters of Guangdong | Gu Dang En, Hu Yinchang, Ocean and Fisheries, No. 10, 2020

9. Crocodile Belly: Overlords in the North American River | Cheng Du, Children's Technology, No. 11, 2013

10. Recently, "Strange Fish" crocodile croaks have been found in many places! What is it? | Han Xueying, Zheng Yan, Voice of China of Central Radio and Television Station, 2022-08-29

11. "Biological Safety Law of the People's Republic of China" | China Government Network

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