In March 2023, the editor saw a message on the Internet:
For the first time in 23 years, the Yangtze sturgeon has spawned naturally.
Note: Screenshot of the webpage in 2023
At that time, many media outlets reported on this matter at great length. For a time, many people were full of expectations for the protection of large fish in the Yangtze River.
After all, in the eyes of the average person, this is great news.
A year later, it's April 2024. The editor saw almost the same news on the Internet, the Yangtze sturgeon has "spawned naturally" in the Yangtze River again, and it is the "first time".
Note: Screenshot of the webpage in 2024
In the past two years, the "first" spawning has been successful twice, and it is estimated that even the Yangtze sturgeon itself has been stunned: have I spawned or not?
Prior to this, the Yangtze sturgeon had been declared "extinct in the wild", mainly because there were no signs of spawning in nature.
If eggs are not laid for a long time, they will not be able to reproduce normally, and it is impossible to maintain the population only by artificial reproduction and release.
But after waking up, the "good news" of the Yangtze sturgeon spawning has completely disappeared the label of "extinction in the wild".
Many people use words such as "first" and "breakthrough achievement" to express their joy. Many self-media people also began to cheer, saying that this was the credit of the ten-year ban on fishing in the Yangtze River, and the ecstasy was overflowing.
But I couldn't be happier!
It only took a dozen months for the Yangtze sturgeon to go from "extinction" to natural spawning?
In July 2022, the Yangtze sturgeon was declared "extinct in the wild" by the International Union for Conservation of Nature.
What is extinction in the wild? It is defined as "extinction in the wild" when an individual of a species is known to live only in captivity, or when it needs to be released from the wild to return to a place where it was once distributed in history.
After more than a year, the Yangtze sturgeon has been declared "natural spawning" twice, is it really so amazing?
Some people may ask, why do you, a "fishing guy", question the conclusions of experts, and why do you always like to contradict them.
In fact, although the status of "fishing guys" is humble, they are a group that is very concerned about the protection of fish resources, and they only want to see the real results.
Let's take a look at what kind of situation some people call "natural spawning".
According to public information, in 2023, the so-called "natural spawning" of the Yangtze sturgeon is in an artificial ovary with a size of 45 cubic meters, by artificially regulating the flow rate of the water body, simulating the environment of the Yangtze sturgeon in the natural spawning grounds, and then guiding these artificially farmed fish to spawn.
You read that right, it's a small pool of just 45 cubic meters.
Many people must be wondering, can this box, which is not as big as a swimming pool, represent the complex natural environment of the Yangtze River?
By 2024, the box containing water will be transplanted to the outside, and the 45-cubic-meter pool will be turned into a 20,000-square-meter test area.
To put it bluntly, it is to artificially simulate the spawning environment required by the natural waters of the Yangtze sturgeon, and then release the artificially released fish, through a series of technology and ruthless work, to prompt them to spawn.
Can this be called "natural spawning"?
It is no wonder that "Wei Qiwei", a graduate researcher at the Yangtze River Fisheries, expressed dissatisfaction with this statement, calling it "inaccurate" and euphemistically criticizing the term "natural spawning".
In Wei Qiwei's view, it is more appropriate to call it "spawning under artificial intervention"!
For the self-congratulatory of some media people, many netizens should be surprised, after all, this model can cater to the public's point of view, and it can also attract the attention of more people, and the people above are also very happy, why not do it.
But no matter how self-conscious these people are, we only look at the real results.
Will the spawning of the Yangtze sturgeon, like some major research and development achievements, stay in the laboratory forever?
Is the so-called "natural spawning of the Yangtze sturgeon" sustainable or replicable?
No one can stand up and respond to these questions.
In the waters of the Yangtze River, the Yangtze sturgeon is not the only fish that can no longer spawn naturally or is losing its spawning function. Among them, the Chinese sturgeon is a typical representative, which has stopped spawning naturally for decades and needs to be artificially reproduced and released to achieve population continuity.
The root cause of this situation is not difficult to understand, for these migratory fish, the spawning process is a migratory journey, if they cannot migrate, spawning is impossible.
The cascade dam in the scene has already changed the flow velocity, water temperature, and the appearance of the riverbed, and blocked the migration routes of migratory fish.
Trenches make it impossible for them to find their way home. At the moment, there is no such thing as a good solution.
Some fish have strict requirements for the spawning environment, and water temperature, water flow rate, dissolved oxygen amount, pH and other indicators will affect their reproduction.
Take the Chinese sturgeon, for example, an ancient and mysterious fish, whose secret to reproduction is closely related to the temperature of the water. They prefer water temperatures below 20°C, need to maintain a dissolved oxygen level of more than 5mg, and have an acid-base balance of about 7.5 pH.
But as the environment of the Yangtze River changes, some factors are changing. According to public data, the average water temperature during the spawning period of the Chinese sturgeon remained at 16.2°C from 1980 to 1983, climbed to 17.8°C between 2002 and 2005, and jumped to 23.8°C in 2013.
Once the environment changes greatly, the reproductive habits of these ancient creatures that have lived for thousands of years cannot quickly adapt to such changes.
These problems are not something that some people can solve by being self-congratulatory.
However, this time, the Yangtze sturgeon has achieved spawning from indoor to wild, although it has not escaped human intervention, but it is still a step forward.
The editor is not a fish expert, just a "fishing guy", a fishing enthusiast who cares about the protection of fish resources in the Yangtze River. I hope that those fish protection workers can really let the Yangtze sturgeon, Chinese sturgeon and other large fish spawn naturally, and it is not too late to come back to the carnival.