[I heard that it was a farewell!] In Yangzhou, you can still see its specimens] # White Sturgeon # This morning, the extinction of the white sturgeon was on the hot search, causing widespread concern among netizens. The reporter learned from the College of Biological Sciences and Technology of Yangzhou University that there is a white sturgeon in the herbarium of Yangzhou University. "This specimen is a long time old, and I had it in the 1980s when I went to Work at Yangda." Wang Aiqin, a senior experimenter at the College of Biological Sciences and Technology of Yangzhou University, told reporters that the container of the specimen was still small at that time, and the sturgeon's kiss was too long to be stored, and the kiss was sawn off for preservation. Until the 1990s, the herbarium re-created a long glass display jar for the white sturgeon specimen and stitched it up again, so the white sturgeon specimen seen now was stitched. "I've never seen it, but I've heard it's a farewell." Ju Tao, a volunteer who has looked for traces of white sturgeon in the Yangzhou section of the Yangtze River, said that since 2007, many people have felt that there may be no white sturgeon in the Yangtze River, and it can be seen in the Yangzhou section of the Yangtze River a long time ago.
We undoubtedly need a correct attitude towards species extinction, on the one hand, species extinction is ancient, even a natural law, on the other hand, human beings need to be vigilant against themselves. Since the birth of life, the earth has so far experienced 5 natural mass extinctions of species, the so-called "natural selection, survival of the fittest", if any species can not adapt to the environment, its extinction should be sooner or later. But in the process of conquering nature, human beings have caused excessive damage to the environment, and indeed many species have been forced into desperate situations.
The extinction of the Yangtze River white sturgeon, the white sturgeon dolphin, the Yangtze River anchovy, etc. is not to blame for humans, in fact, human beings do not have to blame themselves excessively. In the history of life on earth, natural disasters, environmental changes, etc. have led to five mass extinctions, leaving aside accidental factors, many of which are actually eliminated by nature. The white sturgeon is the top carnivorous fish in the Yangtze River, and its population is destined to be fragile. There is a spoon-kissed sturgeon in the Mississippi River in the United States, which is the brother of the Yangtze River white sturgeon, which is currently in a state of "easy extinction", from which we can see a certain "fate" of the white sturgeon.
What reflection can the extinction of the white sturgeon bring to people?
The research paper published online on December 23, 2019 by the international academic journal Science of the Total Environment offers some insights.
In this paper, factors such as habitat fragmentation, degradation, and obstruction of egg-laying migration are re-mentioned.
The researchers wrote in the paper that the development of the Yangtze River and dam construction in the 1970s further reduced the number of individuals in the white sturgeon at that time. As a large carnivorous fish and top predator in freshwater, the population of the Yangtze River white sturgeon may never have increased. Overfishing may have exacerbated its extinction. Habitat degradation is also one of the key causes of the extinction of the Yangtze River white sturgeon.
The corresponding author of the paper is Dr. Wei Qiwei, and the first author of the paper is Dr. Zhang Hui.
According to the paper, the extinction of the Yangtze River white sturgeon is caused by multiple threats, and the protection of endangered species in the Yangtze River Basin urgently needs to be improved in order to avoid more similar extinction events.
The paper said that from the extinction event of the Yangtze River white sturgeon, there are many lessons to be learned. The paper mentions three of them.
First, studies have shown that the key point in time to save the Yangtze River white sturgeon was before 1993 (i.e., before its functional extinction) and at the latest before 2005 (i.e., the projected time of extinction). But all the substantive rescue efforts, such as aquatic exploration, experimental capture surveys at their historic spawning grounds, and artificial reproductive technology studies, were carried out after 2006, and "it was too late to stop their extinction.". For some species, the window of conservation opportunity may have closed. But for other species that are "still alive" and still have individuals alive, it is important to seize the remaining opportunities. The researchers believe that the extinction risk of all endangered species in the Yangtze River should be assessed as soon as possible to determine their conservation measures and priorities, so as to avoid possible further extinction events.
Second, the urgency of prioritizing the conservation of species at greatest risk of extinction is so urgent. Conservation should focus on species that have not been seen for many years or have suffered severe habitat loss and rapid population decline. For example, luciobrama macrocephalus (long-billed eel) and Sichuan white turtle (onychostoma angustistomata) have not been found for many years, but have never even been evaluated on the iUCN Red Species List. In addition, some species, such as cochineal, round-mouthed copperfish, Sichuan Zheluo salmon, Chinese sturgeon, Yangtze River sturgeon, etc., although evaluated, have not seen natural reproduction for many years.
Third, new comprehensive surveys of the entire Yangtze River basin are needed and institutionalized on a regular basis, for example, every five years. The yangtze river basin was first comprehensively surveyed in 1973–1975, and a second comprehensive survey was conducted 41 years later in 2017-2018, the paper said. Due to the lack of sustained records, it is currently impossible to determine the fate of the 140 "disappearing" species in the second survey, such as whether they are extinct. As a result, it is not possible to intervene in a timely and effective manner.
On January 3, a doctoral student at the Yangtze River Fisheries Research Institute of the Chinese Academy of Fishery Sciences told the www.thepaper.cn that the ultimate significance of protecting a species lies in protecting its habitat and preserving the integrity of the natural ecology and the organisms in it.
The doctoral student said that if a species wants to survive, it must have food, shelter, egg laying grounds, and it must survive; it must also have surviving individuals, who must be able to grow, mature, have the ability to reproduce, and maintain a certain population. In the context of conservation, the purpose of any wild animal release is population reconstruction. But the premise of release is to survive in the wild.
Wei Qiwei and his team members rescued the Yangtze River white sturgeon. Wei Qiwei authorized the use of the surging news
The long-nosed Yangtze River white sturgeon also has five brothers. But four of them, people have only seen in fossils. Of the remaining two species, in addition to the Yangtze River white sturgeon, its only remaining brother is the small american spoon sturgeon living in the Mississippi River in the United States. Their long noses are called spoon-snouts, like the long handles of a tablespoon.
According to the above paper, from 1981 to 2003, people saw the Yangtze River white sturgeon 210 times, and only 45 times were recorded in detail: body length, sighting location, fish age, etc.
The vast majority of yangtze river white sturgeon sightings occurred before 1995, with the most common around 1985. Although China had previously banned the fishing of Yangtze River white sturgeon in 1983, bycatch was frequent.
Of the more than 200 Yangtze River white sturgeon sightings, 47 occurred in the upstream section and 159 in the downstream section, accounting for 75.7% of the latter.
Based on the only monitoring records, researchers believe that the white sturgeon that appeared in the Yangtze River during the dinosaur era was extinct as early as 2005 and as late as 2010. "The loss of this large representative species, which is unique and attractive in freshwater ecosystems, is a sad and irreparable loss." They wrote in the paper.