The Yangtze sturgeon still exists, and the World Conservation Union re-evaluated the sturgeon around the world. Known as the "king of freshwater fish in China", the Yangtze sturgeon has been officially declared extinct, but some people still think that it still exists. Let's have a look.

There are 1 paddlefish in the Yangtze River, another endemic species in China, which was declared extinct and failed to enter 2020. A research paper (pre-proof) published online by the international academic journal Science of Total Environment recently revealed this news.

The correspondent of this paper is Dr. Wei Qiwei, chief scientist and researcher of Changjiang Fisheries Research Institute of Chinese Academy of Fishery Sciences, and the first author of this paper is Dr. Zhang Hui.

The researchers said in the paper that it is estimated that the Yangtze sturgeon will be extinct in 2005-20 10. The pre-proof of this paper was published on 20 19 19. In addition to the extinction of the Yangtze River sturgeon, the Chinese sturgeon and the Yangtze River sturgeon endemic to China are still rated as "extremely dangerous".

The paddlefish is the largest freshwater fish in the world, with a maximum length of 7 meters. There is a saying among fishermen in Sichuan that "ten thousand catties of elephants carry wax"-"wax" refers to Chinese sturgeon and "elephant" refers to white sturgeon. This is a big guy.

To tell the truth, sturgeon is ugly. Its head, back and tail fins are all blue-gray, and only its abdomen is white. Sturgeon is naked and has no cover. Only one primitive scale called hard scale grows on the caudal fin.

Its kiss is long and sharp, so it was also called "elephant-nosed fish" by the ancients; The mouth is on the ventral side of the head, and there is only a row of tiny teeth in the mouth. Nevertheless, sturgeon is still fierce and can eat and swallow all kinds of small fish. Sturgeon has a big gill cover and a big mouth, but its eyes are very small, which is a bit funny and grows in front of the mouth near the back of the head.

The sturgeon's tail is also very personal-it is curved and the tail spine is bent upwards. If you dissect the sturgeon, you can also find that its spine is primitive, supported by a rod-shaped notochord, and most of its bones are cartilage. These body structures remind you that it is really old. For hundreds of millions of years, the white sturgeon has been stagnant. Some fossil studies show that the earliest sturgeon species fossils can be seen in the late Jurassic.

Chinese sturgeons lay eggs in the Yangtze River, and then they will take their young fish to the far sea. But the paddlefish is different. It has basically spent its whole life in the Yangtze River, and has been to the Yangtze River estuary at most. The spawning ground of ACIPENSER sinensis is located in the lower reaches of Jinsha River and the main stream of Yangtze River above Chongqing. Mature individuals have the habit of migrating upstream before the breeding season.

As a huge fish that is not outstanding, the paddlefish is "silent". Except the fishermen who deal with the Yangtze River, it is difficult for most people to see the live paddlefish. It doesn't have such a loud name as "Chinese sturgeon". If you can't see or understand it, even fewer people care about its fate.

There are many reasons for the population decline. The paddlefish only live in the Yangtze River. As the flagship species at the top of the food chain in the Yangtze River, its number is small and it is more susceptible to human activities. The deterioration of ecological environment, the decline of biological resources, high-density shipping, water conservancy projects, illegal power grids, hooks ... all these make the situation of sturgeon more and more difficult.

On June 5438+February 1 1 day, 2002, a female paddlefish with a body length of 330 cm and a weight of 1 16 kg was captured by fishermen in Xiaguan waters of Nanjing, Yangtze River. This ACIPENSER ACIPENSER is seriously injured, with several rolling hooks on its body and a wound about 22 cm long in its jaw.

This is the only living paddlefish found in the world in recent 10 years. At that time, the Ministry of Agriculture ordered the rescue at all costs.

However, at the beginning of June 5438+ 10, 2003, this paddlefish was declared dead. The experts tried hard for a month, but failed to revive it. At that time, the media wrote: No one knows if this is the last white sturgeon on earth.

In 2009, IUCN assessed the endangered species of the Yangtze River paddlefish as "extremely dangerous". But for many years, the Yangtze sturgeon has never appeared in the hard search of fishermen and scientists. No one could have imagined that this might be the last time people discovered the Yangtze River paddlefish. If you lose this fish, you lose the whole species.

Netizen lamented: We have never met, and I heard it was farewell. The news of "the extinction of paddlefish" is distressing:

Recently, the Ministry of Agriculture and Rural Affairs issued a notice to implement the 10-year fishing ban plan of the Yangtze River in the natural waters of the main stream and important tributaries of the Yangtze River except aquatic nature reserves and conservation areas for aquaculture.

Under the rapid and extensive economic development model in the past few decades, the biological integrity index of the Yangtze River has reached the worst "no fish" level. Therefore, it is extremely urgent to realize the ban on fishing and let the Yangtze River recuperate.

The Yangtze River is an important ecological treasure house in China, with more than 4,000 species of aquatic organisms, and it is one of the rivers with the richest aquatic biodiversity in the world. In 1988 list of national key protected wild animals approved by the State Council, there are 9 species of fish in the Yangtze River basin, namely the first-class protected animals, namely ACIPENSER sinensis and ACIPENSER Changjiang.

In addition to the extinction of the Yangtze River sturgeon, the Chinese sturgeon and the Yangtze River sturgeon endemic to China are still rated as "status" by IUCN. On 20 17 and 20 18, the Ministry of Agriculture and Rural Affairs successively launched the Chinese sturgeon rescue action plan and the Yangtze sturgeon rescue action plan.

According to Sina Weibo @ People's Daily, the implementation of the 10 year fishing ban plan in the Yangtze River will be the largest fishing ban in the history of the Yangtze River. As the ancients said, fish and turtles can't be eaten without counting, but due to overfishing, the Yangtze River has fallen into a "fish-free" situation.

Fish should be released, and people should reflect. There is no fish when fishing is exhausted, and the law is respected. The rise and fall of fish is essentially the indicator light that nature lights up for development. Give the Yangtze River 10 rest period, and the Yangtze River will bring vitality to the world.

The Yangtze River paddlefish also has two "living fossils" of fish.

I haven't met. I've heard for a long time. For most of us, the Yangtze River paddlefish is such a rare species, but now the last Yangtze River paddlefish has also sunk into the rolling Yangtze River water.

The Yangtze sturgeon, also known as "anglerfish" and "tuna", is also known as "elephant-headed fish" and "elephant-nosed fish" because of its long snout, belonging to Noctuidae.

The ancient books made a refined summary of the morphology of the paddlefish.

"The mouth of the tuna is under the jaw, and the nasal cartilage is older."

The head of the Yangtze sturgeon accounts for one-third of its body length, and its snout is like a nose, which gradually widens from front to back. The sturgeon stamps issued by China vividly depict the sturdiness of sturgeon.

It is worth mentioning that the origin of Polypodiaceae can be traced back to 65.438+0.5 billion years ago. That period was the longest Cretaceous in Phanerozoic. The climate in Cretaceous was quite warm, the sea level changed greatly, and the fishes of the family Polyodontidae also multiplied rapidly. However, due to the drastic environmental changes in the Quaternary Ice Age, only the Yangtze River sturgeon in Asia and the Mississippi River long-nosed sturgeon in North America survived. This article is about Asian Yangtze sturgeon.

The Asian Yangtze paddlefish, the largest freshwater fish in China, lives in the middle and upper reaches of the Yangtze River and belongs to the first-class protected animals in China. They are large ancient fish in the Yangtze River basin, second only to the Chinese sturgeon. They are 2~3 meters long and weigh 200~300 kilograms, making them one of the largest freshwater fish.

However, due to the deterioration of the ecological environment, there are fewer and fewer active areas and individuals in the Yangtze River, so the paddlefish is also known as the "giant panda in the water".

However, with the death of the last Yangtze sturgeon, the Yangtze sturgeon can only exist in the film.

Now there are only specimens of paddlefish left.

As the largest freshwater fish in China, paddlefish can be called "the king of freshwater fish". They escaped the drastic environmental changes brought about by the Quaternary Ice Age and survived for 65.438+0.5 billion years in the world with many natural enemies.

However, such an ancient creature failed to live the New Year in 2020.

When people were celebrating the New Year, the last Yangtze sturgeon sank to the bottom of the river, announcing the extinction of the Yangtze sturgeon. Now, let's discuss the reasons for the extinction of the Yangtze sturgeon.

Bodies of ACIPENSER sinensis found in the Yangtze River

The first is the culture of the Yangtze sturgeon. The data show that it takes more than 7 years for sturgeon to survive in natural waters. The bigger the sturgeon, the stronger its spawning capacity and reproductive capacity.

However, although the paddlefish can lay more than 200,000 eggs at a time, the success rate of hatching fish eggs is very low. Some of them were eaten by natural enemies, and some just hatched and died because they didn't adapt to the deteriorating environment around them.

Secondly, human overfishing has led to a sharp decline in the number of paddlefish. If the environmental upheaval caused by the Quaternary Ice Age is the first difficulty of Chinese sturgeon, then overfishing is the second.

Before the 1960s, the population of the Yangtze River paddlefish was still in a state of equilibrium.

In 1970s, the number of paddlefish began to decrease sharply, and many people fished for profit. From a distance, the numerous fishing boats, "electric poison bombing" and "sterilization nets" on the Yangtze River have made the Yangtze River white sturgeon caught in large quantities. Even the fry hatched by Lian Gang, a black-hearted fisherman, survived.

Then, the environment on which the Yangtze sturgeon lived was destroyed. With the acceleration of industrialization and urbanization and the rapid development of township enterprises, high-rise buildings along the Yangtze River have mushroomed, and at the same time, the water pollution problem in the Yangtze River basin has become increasingly prominent.

Especially in the middle and lower reaches of the Yangtze River, problems such as eutrophication, white pollution and water ecological imbalance are particularly serious.

This not only brings great challenges to the living environment of human beings, but also threatens the extinction of aquatic animals in the Yangtze River basin.

Whether spawning, reproduction or survival, the Yangtze sturgeon is highly dependent on the surrounding environment. With the serious pollution of water resources in the Yangtze River basin, the number of paddlefish in the Yangtze River has also dropped sharply.

Then there is the food shortage of sturgeon in the Yangtze River. As mentioned above, during the Quaternary Ice Age, only the Mississippi river long-nosed sturgeon in North America and the Yangtze river paddlefish in Asia survived.

These two species are of the same period, but their food habits are completely different. Acipenser longsnout is a filter-feeding fish, and Acipenser sinensis is a carnivorous fish, which is the middle layer of the aquatic animal food chain in the Yangtze River basin.

The overfishing of human beings and the bad changes in the environment of the Yangtze River have not only affected the Yangtze River paddlefish, but also affected many other aquatic animals. This led to a sharp drop in the amount of food of the Yangtze River paddlefish, and the Yangtze River paddlefish lived a life of lack of food, and the number naturally decreased.

The last reason is that people stop rivers and build dams. The Yangtze sturgeon is a migratory fish. Due to the construction of dams and power generation facilities in the Yangtze River basin, the growth and reproductive capacity of the Yangtze River sturgeon and other migratory fish have been seriously damaged.

The extinction of the Yangtze sturgeon has become a fact that we can't change. Who would have thought that the Yangtze sturgeon, which survived for 65.438+0.5 billion years, could not cross the New Year in 2020?

When the last Yangtze sturgeon sank to the bottom of the river, the sturgeon quietly disappeared into the Yangtze River. The Yangtze paddlefish seems to have played a sad song to mankind with its life.

They seem to regret why humans didn't take action to save themselves earlier. In Lu's Spring and Autumn Annals, it is mentioned that "fishing as much as you can, wouldn't you get it?" ? There will be no fish next year. "

However, despite the advice of our ancestors, human beings have been fishing crazily since 1970s, and even the fry hatched in Lian Gang have survived.

People should really take action as soon as possible to save fish. When the fish are exhausted, they should stop fishing. It was only when humans began to realize that the fish in the Yangtze River basin should be protected that it was too late.

During the period of 1993, the functionality of ACIPENSER Changjiang has been extinct, and it is expected that 2005 will be the time for the extinction of ACIPENSER Changjiang.

It is hard for us to imagine how the Yangtze sturgeon faced its partners to death one by one, leaving itself alone to face the turbid river around it. The Yangtze sturgeon struggled for five years, but still couldn't wait to be rescued.

We can't save the Yangtze sturgeon now, but we can save other endangered species in the Yangtze River basin. It is urgent to give priority to the protection of the species with the greatest risk of extinction, and human beings have taken corresponding measures.

202 1, 1, 1, the Yangtze River officially began to implement the "ten-year fishing ban" policy. No-fishing areas are divided into three categories, the first category is aquatic life protection areas, the second category is the Yangtze River and its important tributaries, and the third category is other key waters. People firmly believe that "fishing is forbidden for ten years before there is fish."

Some people here will question why the Yangtze River has been closed to fishing for ten years before it started fishing again.

In fact, this is because under the protection of people, some herbivorous fish and omnivorous fish recover faster, grow healthier and reproduce faster.

This has led to a sharp increase in the number of these fish, but rivers and lakes have the best and suitable carrying capacity. Once beyond this range, water resources will deteriorate, so people start ecological fishing.

Moreover, ecological fishing only involves several lakes and reservoirs in the pilot area where fishing is prohibited, and the state still implements the strictest fishing ban policy on the main streams of the Yangtze River and the Han River.

Nowadays, human beings pay more and more attention to the harmony between man and biology and between man and nature. Under the protection of human beings, although the endangered state of some organisms has not changed, the situation of sharp decline in population has been improved.

We should bid farewell to the Yangtze sturgeon, learn a lesson, and do our best to protect other endangered animals and prevent some animals from becoming endangered. We really don't want future generations to experience the scene of "never meeting, I heard it was farewell" again.

The Yangtze sturgeon still exists. The Yangtze River paddlefish is extinct! Will the Chinese sturgeon be next?

Published by IUCN.

Update Report on Global Red List of Endangered Species

Declare the white sturgeon extinct

Wild extinction of Yangtze sturgeon

This news quickly boarded the first hot search in Weibo.

According to the latest report of IUCN official website.

All 26 species of sturgeon in the world are threatened with extinction.

The re-evaluation results of IUCN global sturgeon show that

About two-thirds of the sturgeon population is extremely endangered.

Image source: WWF World Wide Fund for Nature

They also lived with dinosaurs.

Sturgeon population is a unique unit in the phylogenetic tree. The geological age of the ancestors of giant pandas is only 8 million years, and the sturgeon fossils can be traced back to the Mesozoic Triassic, which means that they once existed with dinosaurs and were really "living fossils in water".

Most existing sturgeon-like fish are very large. The longest sturgeon, once the largest freshwater fish in the world, can reach 7.5 meters and the Chinese sturgeon can reach 4 meters. Sturgeon mostly spawn upstream, which is distributed in the relatively wide water surface of the big rivers and coastal shallow waters in the northern hemisphere. As an important link of information and material exchange between oceans and rivers, they have become indicator species of ecological conditions in the northern hemisphere and reliable indicators for measuring aquatic biodiversity.

"The most threatened group in the world"

In recent centuries, human activities have intensified, and the natural population of sturgeon has dropped sharply and is on the verge of extinction. Known as "the most threatened group in the world."

On a global scale, the main threats faced by sturgeon include: fishing caused by illegal trade in wild caviar and fish, dam blocking migration routes, unsustainable sand mining destroying spawning grounds and habitat loss.

Wei Qiwei, a member of the Chinese sturgeon expert group of the World Conservation Union, a researcher at the Yangtze River Research Institute of the Chinese Academy of Fishery Sciences and the founder of the Yangtze River Chinese Sturgeon Protection Center in Wuhan, made a comparison between Chinese sturgeon and baiji: "The ecological habits of Chinese sturgeon and baiji are different, one breeds in the upper reaches of the Yangtze River, and the other habitat is mainly in the middle and lower reaches of the Yangtze River, but their extinction fate is similar to that of the period. This is not an accident, but a profound lesson. Other aquatic creatures in the Yangtze River must not make the same mistake.

What about Chinese sturgeon?

The flagship species of the Yangtze River, ACIPENSER sinensis, has also been decreasing in recent years. 1988 is listed as a national first-class wild protected animal, and 20 10 is listed as an extremely endangered species by IUCN.

Artificial propagation and release have always been one of the important measures for species protection of Chinese sturgeon. As of last year, more than 7 million Chinese sturgeons have been released by many institutions including the Chinese Sturgeon Research Institute for more than 30 years.

On May 22nd, 20 19, the field population of Acipenser changjiangensis in Yibin was rebuilt. Image source: WWF World Wide Fund for Nature

However, the researchers said that it is very difficult to recover rare and endemic species, and they are still racing against time to minimize the adverse effects of the decline of wild resources on the reproduction of Chinese sturgeon population.

"At present, the Yangtze River Rare Fish Protection Center, together with the supporting construction of the Chinese sturgeon sperm and tissue cell bank, is running better and better. Basically, it can be guaranteed that the Chinese sturgeon will not take the old road of the extinction of the baiji, and the species will continue forever. " Li Zhiyuan, Party branch secretary and deputy director of Chinese sturgeon research institute, said.

Protect the species of the Yangtze River

We've been trying.