Farewell, Bai？ Dolphin-Dialogue Zoologist Zhou Kaiya
White dolphin, a rare mammal unique to the Yangtze River in China, is known as the "giant panda in the Yangtze River". In the cries of salvation, this ancient aquatic animal finally went to decline-
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Profile picture: white? suckling pig
At the end of last year, scientists from many countries carried out a 38-day investigation of freshwater dolphins in the Yangtze River with the most advanced instruments, but no white dolphin was found.
An old professor who had a half-life relationship with the white dolphin watched the creature leave. He blamed himself for failing to save Bai in the 1980s. Dolphins do more and more effective work.
This is the helplessness of a zoologist. In the face of the deteriorating Yangtze River habitat, his rescue plan with scientists at home and abroad failed. In helplessness, let us remember the last white dolphin.
At the end of last year, scientists from many countries carried the most advanced instruments and conducted a 38-day investigation of freshwater dolphins in the Yangtze River, but no white dolphin was found. Is the ancient white dolphin really dead?
With questions, the reporter came to Zhou Kaiya, a professor and doctoral supervisor of Nanjing Normal University.
An accidental acquaintance in the 1950s made Zhou Kaiya have an indissoluble bond with the white dolphin. This 75-year-old professor is known as "the rediscover of the white dolphin". But watching the white dolphin fade away, he was helpless …
White dolphins reappeared in the 1950s.
Reporter: Under what circumstances did you come into contact with the white dolphin? Zhou Kaiya: Very accidental. In 1956, a fisherman caught a strange "big fish" in the Yangtze River in Nanjing, and was sent to the Biology Department of Nanjing Normal University (the predecessor of Nanjing Normal University) to make a specimen, but no one could name it. In 1957, I returned to Nanjing Normal University after completing my studies at the Institute of Zoology, Chinese Academy of Sciences, and I first saw this "strange fish" specimen. I was curious and wanted to find out what it was, so I looked up a lot of domestic and foreign materials.
Reporter: Are there any records of white dolphins in the Yangtze River in China abroad? Zhou Kaiya: Yes. I found out in the international journal of zoology that in 1916, Hoy, the son of an American missionary, killed a "strange fish" with a shotgun in Dongting Lake. This "strange fish" is two meters long, with a long and narrow beak, a blue-gray back and a milky belly … Local fishermen call this fish "white". After that, it was made into specimens and sent to the Washington Museum of Natural History in the United States.
Appraised by American mammal scientist Miller, this is a rare freshwater dolphin in the world, and it is a mammal living in fresh water. Because Huo Yi mistook the word "white" spoken by fishermen in China for "white flag", the English name of this freshwater dolphin was named "white flag dolphin".
Reporter: The name of "White Dolphin" evolved from "White Flag Dolphin"?
Zhou Kaiya: Right. Especially in the 1950s, the "white flag" had a special derogatory meaning. Therefore, in the mid-1950s, the Compilation Bureau of China Academy of Sciences translated "Baiqi Dolphin" into "Baiqi Dolphin". But this name is not true, and it is also a misunderstanding. I’ll explain later why this is a misunderstanding.
Reporter: Haven’t Chinese scientists studied the white dolphin? Zhou Kaiya: Before 1918, the only freshwater dolphins identified in the world were the Ganges River in South Asia, the constant puffer fish in the Indian River, the Asian puffer fish in the Amazon River and the Orinoco River in South America, and the Fauci dolphin along the Atlantic coast of South America. The specimen discovered by Hoey was named "White Flag Dolphin" after Miller’s research. He believes that the "White Flag Dolphin" living in Dongting Lake in China and the nearby Yangtze River belongs to the family Subtetrodotoxus, just like the Subtetrodotoxus in the Amazon River in South America.
In the following decades, China was constantly at war. Except for the British Museum of Natural History in South Gansington and the American Museum of Natural History, foreign scholars and China scholars never cared about this rare mammal again. The white dolphin was gradually forgotten, and there was no news again. It is only recorded in zoology textbooks that there is a freshwater dolphin in China, which is only active in Dongting Lake and its nearby middle reaches of the Yangtze River.
Reporter: How can you be sure that the "strange fish" specimen of Nanjing Normal University is the white dolphin?
Zhou Kaiya: The identification of mammals is mainly based on the shape and teeth of bones, especially skulls. The skull of this "strange fish" has a square rear edge, the zygomatic process of the squama is particularly strong, and the upper and lower jaws are extended into a long and narrow beak; The teeth are tapered, the root of the teeth is flat, and there are more than 30 teeth on each side of the upper and lower jaws; It is two meters long, with a narrow beak with a slightly upturned front section, a blue-gray back and a triangular dorsal fin … The appearance and skeletal characteristics of the "white flag dolphin" recorded in the literature are exactly the same as that of the "strange fish" specimen in our college. It is the white dolphin. Reporter: According to records, the white dolphin only lives in Dongting Lake and its nearby waters in the middle reaches of the Yangtze River. Zhou Kaiya: Yes, it made me very confused when I was only 25 years old. Did this white dolphin just happen to appear in the lower reaches of the Yangtze River, or did it have a larger distribution range? I must look for evidence.
Many fishermen I visited said that they had seen this kind of "fish" in the Yangtze River near Nanjing. In August, 1957, Nanjing Fishery Cooperative captured a 2.06-meter-long white dolphin near Pukou Ferry Terminal. Since then, I have also seen two white dolphin specimens in Shanghai Tiger Hill Museum, both of which were obtained in the Yangtze River estuary near Shanghai.
These evidences prove that there are also white dolphins in the lower reaches of the Yangtze River. In 1958, I published "baiji dolphin found in the lower reaches of the Yangtze River" in Science Bulletin, which corrected the argument of foreign scholars that the distribution of baiji should extend eastward from Dongting Lake and its nearby middle reaches of the Yangtze River to Nanjing-the lower reaches of the Yangtze River near Shanghai.
Reporter: The white dolphin was rediscovered. Is there a turning point in its unknown fate?
Zhou Kaiya: After this issue of Science Bulletin was spread abroad, the white dolphin, which many scholars thought had disappeared, once again attracted the attention of the international marine veterinary community. Some time ago, I went abroad for a meeting, and Dr. Palin, President of the Marine Mammal Society, also called me "the rediscover of the white dolphin".
Regrettably, there was no concept of "wildlife protection" in China at that time. My initial research on the white dolphin only corrected a mistake in the zoological literature and did not provide any help to the endangered white dolphin. It still lives in obscurity.
White in the 1970 s? Correcting dolphin’s name
Reporter: I heard that you resumed your research on the white dolphin after 16 years? Zhou Kaiya: At that time, no one paid attention to the living condition of this ancient animal. In 1974, the Editorial Committee of Fauna of China Academy of Sciences invited me to participate in the compilation and research of Fauna Cetacea, and was responsible for the compilation of four species entries, among which was "Baiji dolphin". So, after a lapse of 16 years, by coincidence or fate, I began to study the white dolphin again, and it was out of control. Reporter: Was it restricted by the research conditions at that time? Zhou Kaiya: At least I have a research fund, not much, more than 1,000 yuan. With this fund, I visited Hubei, Hunan, Jiangxi, Anhui, Jiangsu and Shanghai alone to find clues about the white dolphin. After running for more than three months, I asked the local old fishermen about the situation and went to the Yangtze River in a small fishing boat to find the white dolphin.
Reporter: Have you gained a lot? Zhou Kaiya: Yes. Although I didn’t see the white dolphin with my own eyes, I found that the distribution range of the white dolphin is larger than originally known, and it can push more than 200 kilometers westward from the Yangtze River section of Dongting Lake to the Huangling Temple and Liantuo River section of the Three Gorges. To the east, it can not only go directly to the mouth of the Yangtze River, but even haunt Fuchunjiang River in Zhejiang Province.
Reporter: It is also through this investigation that you have different views on the name of Baiji Dolphin?
Zhou Kaiya: Yes. Although "White Flag Dolphin" is translated as "Baiji Dolphin". But the fin of this freshwater dolphin is not white. This Chinese name is also easy to cause misunderstanding. With the help of the professor of Chinese Department of our college, we found the description of "Shi" in the ancient book Erya, saying that "Shi" is an animal similar to a dolphin. Fishermen along the Yangtze River have always called this water beast "white" and "green".
In March 1977, my assistant and I wrote an article in the Journal of Zoology, proposing that the Chinese name should be changed to "White Dolphin" according to the widespread use of the masses and historical records. In this way, the name of the white dolphin, which has been passed down through the ages, has been corrected after more than 60 years of misinformation.
Reporter: When did your deeper research on the white dolphin begin?
Zhou Kaiya: After the Cultural Revolution, the government began to re-attach importance to science and support scientific research. Therefore, the topic of investigating and protecting the white dolphin has finally been put on the agenda. The conditions for scientific investigation have been greatly improved. I took a research boat many times and went up the river from the lower reaches of the Yangtze River to find the white dolphin. In 1979, I witnessed the white dolphin for the first time in the Taiyangzhou section of Tongling. Since then, there have been more and more opportunities for close contact with white dolphins.
Our research on the white dolphin is also deepening step by step. From the initial distribution, to morphological structure, taxonomy, ecology, biochemistry, and then to molecular phylogeny … In 2005, we also published the article "Molecular Phylogenesis of Freshwater Dolphins and Mitochondrial Genome of White Dolphins" in the international authoritative academic magazine "Molecular Phylogenesis and Evolution".
Reporter: Did you suggest the establishment of the white dolphin family in animal classification? Zhou Kaiya: Yes. Although in the international authoritative books, the white dolphin was once considered to belong to the subfutus family with the subfutus of Amazon River and Orinoco River in South America. However, through research, we found that its skeleton, stomach and other structures are different from those of sub-puffer fish, constant puffer fish and Fauci dolphin. Therefore, it was put forward for the first time in 1978 that the white dolphin is the existing representative of another kind of ancient toothed whale, and a new family-the white dolphin family should be established; From the end of last century to the beginning of this century, our research group and many research groups in different countries used different DNA markers to study molecular phylogeny, and all supported an independent white dolphin family. The white dolphin living in the Yangtze River in China has finally found its proper place in animal taxonomy.
At the beginning of this century? Dolphin "may be extinct"
Reporter: At the end of last year, scientists from many countries carried advanced instruments for a 38-day investigation of freshwater dolphins in the Yangtze River, but no white dolphin was found. Is the white dolphin extinct?
Zhou Kaiya: World Conservation Union? IUCN? The red list of threatened species is divided into endangered, endangered, extremely endangered and extinct grades. According to the result that a white dolphin was not found during the 38-day investigation, experts attending the seminar on the red list of cetaceans held in the United States in January 2007 suggested that the white dolphin be classified as extinct (possible). That is to say, the white dolphin may be extinct, but it cannot be said that it is definitely extinct. I’m not surprised by the findings themselves. To my surprise, this time came too fast. At present, there may be a small number of white dolphins in the Yangtze River, but as a species, its natural population has no possibility of recovery. Because the white dolphin is the only existing representative of the family Dolphinidae, its extinction is the disappearance of a branch of the evolutionary tree.
Reporter: Is there really no chance at all? Zhou Kaiya: Unfortunately, there is no chance at all. Ex situ conservation of the white dolphin is our last chance. However, we failed to foresee that the Yangtze River basin’s economic development is so fast, the scale is so large, and the habitat of the white dolphin is so severely destroyed, so we didn’t expect the extinction time to come so fast that it was too late to implement more effective protection measures. This is the contradiction between species protection and economic development. It is difficult to reconcile by zoologists alone.
Reporter: Have humans worked hard to continue the fate of the white dolphin? Zhou Kaiya: I tried, but I failed. Since the 1980s, with the development of economy, shipping on the Yangtze River has become more frequent, and the deterioration of ecology is hard to stop for a while, which has brought great survival crisis to the white dolphin. We have been calling for "protecting and saving the white dolphin". In 1982, I published "Protection of White Dolphins", pointing out that the number of white dolphins is only 400 at most, and put forward an ex-situ conservation plan, hoping to keep the white dolphins in captivity and establish the technology of artificial breeding of white dolphins. International organizations such as IUCN/SSC Whale Expert Group, IUCN/SSC Conservation and Breeding Expert Group, World Wildlife Fund (WWF) and many foreign scientists have provided assistance to us. Together with us, we organized international seminars on the protection of white dolphins in Wuhan and Nanjing; Sponsor our investigation, sponsor us to print posters, publish popular science books and distribute them to fishermen in the Yangtze River and middle schools along the coast. However, compared with the sharp decrease in the number of white dolphins, our protection plan measures are lagging behind or even helpless.
Reporter: Aren’t there many white dolphin protection stations on the Yangtze River?
Zhou Kaiya: There is a national white dolphin nature reserve and five white dolphin protection stations on the Yangtze River, but there is no good protection method for such reserves or protection stations, and even white dolphins are rarely seen. Hubei Shishou Tianezhou Yangtze River Old Course White Dolphin Nature Reserve aims at ex situ conservation. In 1996, a white dolphin was caught and put into the reserve, but died six months later. In 1980, the first live white dolphin "Qiqi" captured in Hubei was sent to the Institute of Hydrobiology of Chinese Academy of Sciences in Wuhan for artificial breeding, and I have visited it many times. Its adaptability is relatively strong, but it is only an example. We haven’t fully mastered the method of raising white dolphins artificially. The other three white dolphins "Rongrong", "Lianlian" and "Pearl Krabs" raised by the Institute of Aquatic Biology all died in the end.
Reporter: Have you ever raised white dolphins yourself? Zhou Kaiya: Yes. On March 4, 1981, a white dolphin ran aground on the bank of Taicang River and was rushed to Nanjing Normal University. Stranded dolphins are usually sick, but we didn’t know this at the time. We keep this white dolphin in a special breeding pond in our school. I watch it every day, hoping it can adapt to the life in the breeding pond. But after more than ten days, the white dolphin’s physical strength became worse and worse, and it became weak when swimming, and finally died. After dissection, it was found that there was a serious ulcer in its stomach. It died of a serious illness. I watched it sink straight and never came up again. I feel terrible, and I feel terrible until now.
Reporter: In 2002, Qiqi left the world. Since then, are there no more surviving white dolphins artificially raised?
Zhou Kaiya: Not anymore. We know that the time left by the white dolphin is running out, and we hope to catch the white dolphin and raise it in Shishou or Tongling reserve. However, we never found a living white dolphin. After 1996, I didn’t visit the white dolphin on the Yangtze River myself. Around 2000, I heard fishermen say that they had seen the white dolphin, but they couldn’t confirm it.
Reporter: You suggested the establishment of the white dolphin family, but the only species of this newly established family is now "possibly extinct". As a zoologist, your feelings must be different from those of ordinary people?
Zhou Kaiya: If we had known that the white dolphin would be extinct so quickly, we should have applied to the state for special protection funds long ago. At the beginning, with an investment of 200 million yuan, the ex-situ conservation technology of the white dolphin would have developed greatly and it would be possible to save this ancient species. But we didn’t do it, because we didn’t know the white dolphin would die out so quickly!
Really, if 200 million yuan can be used to save the white dolphin, the country is willing to invest, but we have not applied. If zoologists are unable to control the development of shipping and the deterioration of habitats, we can at least find ways to protect ex situ. But we missed the opportunity, it was too late.
In the protection and research of the white dolphin, we have left valuable information for future generations, and even more painful lessons. (In-depth report group reporter Yin Jun intern Zhao Yangkuan)
Editor: Li Xingcun