Now the Chinese dragonfly and the Yangtze River dragonfly are also nearextinction, the Chinese dragonfly has not been natural breeding for the third year, the Yangtze River dragonfly has not been natural breeding for 20 years, if left to develop, they are the next Yangtze River white dragonfly. “I’m so dumb that I can’t speak. On the evening of January 3rd, Mr. Wu told the Beijing News by telephone. For the past three days, he has been unable to remember how many media interviews he has given.
Wu Qiwei is the chief scientist of The Yangtze River Fisheries Research Institute of China Aquatic Science Research Institute, a well-known expert in fish conservation biology in China, who has carried out systematic research on the species protection technology of a variety of rare and unique fish, and promoted the establishment of a macro-policy and protection technology system for rare aquatic animals in China.
On January 2nd, on December 23rd last year, he published an online paper in the international academic journal Total Environmental Science entitled “What lessons the extinction of the white stork has left in the conservation of the Yangtze River”, which attracted public attention. China’s rare species of yangtze river white stork is expected to be extinct between 2005 and 2010, the paper said.
Dubbed the “King of China’s Freshwater Fish”, the Yangtze River white dragonfly in a near-“tragic” way to usher in unprecedented attention of public opinion, some netizens said, “the first time I heard, has been extinct.” As of January 4, the topic of “The Last Trail of the Yangtze River White Dragon” still occupies a hot search list on a social platform, with nearly 40 million views on the information.
The Yangtze River is a unique fish in the Yangtze River, with a shuttle-shaped body, although called “white” dragonfly, but only the abdomen is white, the head, back and tail fins are green gray. Its head is more than half the length of the body, and the kiss part accounts for nearly three-fifths of the head, protruding like a sword.
Adult Yangtze River white slugs can weigh up to 500 kg, body length up to 7 meters, in the Yangtze River fishing proverb sage called “the elephant.” According to the famous zoologist Bing Zhi records, Nanjing has been captured 7 meters long Yangtze River white slug, the world’s highest freshwater fish body length.
From the fossil record, the Yangtze River white dragonfly is older than the Chinese dragonfly known as the “living fossil”. In history, the Yangtze River has been distributed in the Liao, Haihe, Yellow, Huaihe, Yangtze, Qiantang and coastal areas, but since the 1950s, it has been found only in the Yangtze River and its estuaries. However, at that time, the Yangtze River white slug swashes were still a common fish in the Yangtze River, and in the 1970s, 25 tons of the Yangtze River were captured each year.
“Since the late 1970s, the number of white slugs in the Yangtze River has declined sharply due to overfishing and habitat fragmentation. With the sharp decline in numbers, the Yangtze River white stork has been listed as a national priority for animal protection in China since 1989, and the Yangtze River white dragonfly is listed as “extremely dangerous” in the Red List of Endangered Species issued by the International Union for Conservation of Nature in 1996, he wrote in the paper.
It is understood that the red list of endangered species is classified as 9 levels, “extremely endangered” representative of the degree of endangered second only to “wild extinction” and “extinction.”
On January 3rd, the IUCN said on its official microblog that the final results of the ongoing comprehensive assessment of the Asia-Europe fish had not yet been released and that it was expected to update the IUCN Redlist for Threatened Species during the World Conservation Congress in June this year to officially release the results of the assessment and the corresponding level adjustments.
Here’s a conversation between a Beijing News reporter and a dangerous reporter:
No sightings of the Yangtze River white dragonfly in China after 2003
Beijing News: You said in your paper: It is expected that by 2005-2010, the Yangtze River white slug has become extinct. What is the basis for this judgment?
Danger: This is the result of the model calculation. The model is based on several aspects of the data we collected, one is the past literature, and the other is that we have recorded the fishing records of the white slugs in recent decades, including fishing locations, biological information (such as weight, age) and so on, and the modelises on which the model is mainly calculated. In addition, the species is a living body, with populations, distribution sites, which will form field monitoring results, based on 210 sightings reported from 1981 to 2003, we estimate that the extinction time of the white herring was 2005-2010.
These data, combined with model calculations, can infer the extent of a species’ decline, combined with the IUCN Red List standard, to determine whether it is functional or extinct.
Beijing News: What is the difference between functional extinction and extinction?
Danger: Functional extinction refers to a species that in nature is no longer able to form a sustainable breeding population. Extinction means that the species disappears completely from nature.
Beijing News: Why is the Yangtze River white dragonfly not artificial breeding?
Dangerous: The Yangtze River white dragonfly has not been a successful case of artificial breeding. Previously due to lack of technical and hardware conditions, the artificial culture of the Yangtze River white slug situ only survived for a maximum of 29 days, and then all aspects of the conditions, we have never captured the living Yangtze River white slug. If earlier, more far-sighted to the Yangtze River white dragonfly rescue pool repair, and so captured to the Yangtze River white dragonfly after raising it, then the Yangtze River white dragonfly may have hope. Now we still do a lot of technical reserves, as long as we can also find the living Yangtze River white dragonfly, there is a ray of hope.
Beijing News: When was the last time you saw the wild Yangtze River white dragonfly?
Danger: January 24, 2003, we received the news that a fisherman in Nanxi, Sichuan Province in the Yangtze River mistakenly caught a tail of the Yangtze River white dragonfly, I immediately led the rescue team rushed to the local, confirmed to be a tail of about 4 meters long, weighing more than 150 kilograms of female Yangtze River white slug, its abdomen also has a large number of fish eggs.
At that time, the Yangtze River white dragonfly was mistakenly caught, and was moved in the fishermen’s boat, has been very seriously injured, the abdomen is all full of blood, the head and tail have obvious bruises. We disinfected it and stitched it up, and placed it close to a cage fish farm. After a day of raising, the Yangtze River white dragonfly improved in injury, we decided to release it, and installed ultrasonic tracking equipment on it. We wanted to keep track of it, but then we lost the signal because the tracking ship was damaged. Since then, there have been no sightings of the Yangtze River white dragonfly in China.
“Unable to reproduce is the main cause of the extinction of the Yangtze River white stork”
Beijing News: What is the cause of the extinction of the Yangtze River white slugs?
Danger: The extinction of the Yangtze River white slugs is caused by a variety of threats.
The inability to reproduce is the main cause of the extinction of the Yangtze River white stork. The Yangtze River white slugs generally lay eggs in the upper reaches of the Yangtze River, the middle and lower reaches of foraging fertilizer, but in 1981 the construction of Gezhou Dam cut off their migratory channels, the larvae of the Yangtze River white slugs can still be through the dam to the middle and lower reaches for food, but the adult Yangtze River white slugs can not return to the upper reaches of spawning.
The second factor is the development of the Yangtze River fishing industry, so that large fish and small fish are beaten by a net, or directly lead to the death of the Yangtze River white slug, or lead to the Yangtze River white slug food less and less.
The third is shipping, the ship vibration is very large, more and more ships, the channel staggered, not only the propellerof of the ship may directly hurt the Yangtze River white dragonfly, by the shipping derived channel rectification, reef, shore protection and other shipping projects on the Yangtze River white slug habitat is also very large.
In addition, habitat loss and fragmentation caused by the construction of lakes, water pollution, urbanization and aquaculture are all important factors that threaten the survival of the Yangtze River’s white slugs.
Beijing News: What damages or effects will the extinction of the Yangtze River white slugs bring?
The Yangtze River is a large ecosystem, a combination of thousands of species that make up the biodiversity of the Yangtze River. The extinction of the Yangtze River white stork first meant that one of the Yangtze River’s flagship species disappeared, a loss of the Yangtze River’s biodiversity, like a large family, a very important family member died.
In addition, from the point of view of species genetic resources, the body structure of the Yangtze River white dragonfly is very special, perhaps to the human development and utilization of new bionic technology and materials to provide inspiration; But these are not possible with the extinction of the Yangtze River white slugs. It is not possible to assess the impact of the extinction of the Yangtze River on the entire Yangtze River ecosystem.
“Don’t wait for it to be functionally extinct and then protect it.”
Beijing News: What is the survival status of other fish in the Yangtze River?
Danger: In 2016, the Ministry of Agriculture launched a project “The Yangtze River, Tibet Fisheries Resources and Environment Survey”, the project for five years, has been implemented for more than three years, we found that there are more than 430 species of fish in the Yangtze River, but there are more than 140 species of fish, we have not collected specimens, the Yangtze River white slug is one of them. This shows that these fish in the Yangtze River has been scarce or even extinct, the ecological condition of the Yangtze River has been very serious.
Beijing News: What lessons have been left by the extinction of the Yangtze River’s white slugs to protect the rare species of the Yangtze River?
Danger: First of all, some species don’t wait for it to become functionally extinct and then to protect, it’s too late. Fish stocks are lagging behind in their response to a variety of human threats. Studies have shown that the key rescue moment for the Yangtze River white slug was before 1993 (the year of functional extinction) or at least 2005 (the year of the estimated extinction). But all the real relief efforts, including underwater transmission and trial capture in historic spawning grounds, and research on artificial female nuclear development techniques, were carried out after 2006, when it was too late.
Now the Chinese dragonfly and the Yangtze River dragonfly are also nearextinction, the Chinese dragonfly has not been natural breeding for the third year, the Yangtze River dragonfly has not been natural breeding for 20 years, if allowed to develop, they are the next Yangtze River white dragonfly, but at present their protection is not at the national level and put into practice.
Second, many dams in the Yangtze River can not be eliminated in the short term, but we can mitigate the impact of other human activities, such as fishing, shipping, which requires all sectors around the “healthy Yangtze River” goal to do things, each responsible.
In addition, many species in the Yangtze River basin are considered to be on the verge of extinction, and it is necessary to assess the risk of extinction in appropriate ways as soon as possible in order to take appropriate conservation measures and prioritize them to avoid more potential extinctions.
Zhang Shengpo, reporter for the Beijing News