[Source: Yangtze River Daily-Yangtze River Net]
Yangtze River Daily, Wuhan, March 29 (Reporter Jin Wenbing, intern Li Yuxin) March 28 is the fourth "Chinese Sturgeon Protection Day". On the same day, 10 15-year-old adult Chinese sturgeons and more than 20 second-generation individuals were released into the Yangtze River at the Yangtze River rare fish release point in the Yangtze River. At the same time, 110,000 artificially bred second-generation Chinese sturgeon "babies" also jumped into the Yangtze River at the Jingzhou Changjiang Aquatic Life Enhancement and Release Square, where they swam down the river to add new individuals to the natural population of Chinese sturgeons.
Jingzhou release site. Photo courtesy of Jingzhou Rong Media Center
At the Yichang release site, staff implanted sonar markers to continuously track and monitor the migration of the released Chinese sturgeons after they returned to the Yangtze River, and the Jingzhou Chinese Sturgeon Conservation Center also conducted "electronic identity authentication" on some Chinese sturgeon seedlings to evaluate the release effect.
Jingzhou release site. Photo courtesy of Jingzhou Rong Media Center
Wei Qiwei, a researcher at the Yangtze River Fisheries Research Institute of the Chinese Academy of Fishery Sciences and director of the Wuhan Yangtze River Chinese Sturgeon Conservation Center, has been studying Chinese sturgeons for 40 years. In 1983, he said, the mainland achieved artificial breeding of Chinese sturgeon (wild broodstock) downstream of Gezhouba. However, artificial breeding only retains the genes of the Chinese sturgeon, but does not allow the Chinese sturgeon to exert its ecological value, and the number of Chinese sturgeon in the wild is still decreasing. For this reason, the mainland began to breed and release water 40 years ago. "In the past 40 years, we have released 8 million Chinese sturgeons, but most of them are fry in the early days, the survival success rate is very low, the release effect is not good, and there are still few individuals that can reproduce each year. The last recorded natural reproduction was in 2016. ”
The Chinese sturgeon is a migratory fish in the river and sea, and after birth, it will return to the sea to fatten, live in the sea for 10-15 years, and only return to the Yangtze River again after sexual maturity, following the path that its parents once walked, and returning to its birth to lay eggs. Previously, they went to the lower reaches of the Jinsha River to spawn in the Pingshan River, and later opened up a new spawning ground 4 kilometers below Gezhouba. However, due to the influence of water level, water temperature and many other reasons, natural reproduction is always difficult.
A Chinese sturgeon released into the river. Photo courtesy of Jingzhou Rong Media Center
Li Chuangju, director of the Yangtze River Fisheries Research Institute, said that as long as the 10-year fishing ban on the Yangtze River is fully utilized, the "artificial babies" of Chinese sturgeons released after 2021 will grow up for about 15 years and are expected to migrate to the Yangtze River around 2036 to have children.
In the absence of existing spawning grounds, researcher Wei Qiwei also suggested that some new "spawning beds" should be prepared for the Chinese sturgeon, such as the construction of "artificial spawning beds" in the Hudu River, which is about 20 kilometers long and 100 to 200 meters wide, to help the Chinese sturgeon reproduce naturally.
It is reported that the Ministry of Agriculture and Rural Affairs will organize the release of more than 1 million Chinese sturgeons this year, the largest number released in the past years.
[Editor: Zhao Ke]
Disclaimer: The copyright of this article belongs to the original author, if there is a source error or infringement of your legitimate rights and interests, you can contact us by email, we will deal with it in a timely manner. E-mail address: jpbl@jp.jiupainews.com