What are the four first-class protected animals in China (reward 10! )

Elk, white

Elk is an elk,

White is a dolphin.

White:

White-fin dolphin; ; Chinese puffer fish)

The only species of the genus Baiji in Cetacea. Freshwater toothed whale is a specialty of China, distributed in the middle and lower reaches of the Yangtze River. Dongting Lake, Poyang Lake and Qiantang River are also available. The body is spindle-shaped, with a body length of 1.5 ~ 2.5 meters and a weight of 230 kg. The snout is beak-shaped, narrow and long, and the tip of the snout is slightly upturned; Frontal eminence; Small eyes, located under the squab; Ear hole is very small, shaped like a needle eye, located in the back and lower part of the eye; The dorsal fin is a low isosceles triangle, located in the middle of the back, slightly behind; The fin limb is wide, the end is round and blunt, and the trailing edge of the caudal fin is concave crescent; The back is gray or blue-gray, and the ventral surface is white. Dorsal fin, dorsal fin and caudal fin are all gray or blue-gray. When breathing, the head comes out first, the splash is not high, and the tail fin does not come out. Baiji dolphin is good at diving, but it is easy to be injured by the propeller of motorboat and die. Usually in pairs. When the lake rose in the spring that night, the baiji swam to a clean river to mate, breeding from March to April, and each nest had 1 offspring. Feeding on fish, you can catch benthic fish with a long beak.

Lipotes vexillifer, also known as Baiji Dolphin, is known as the "goddess of the Yangtze River" and is a freshwater whale that only lives in the Yangtze River in China. The existing number is very small, estimated to be less than 50, which is the most endangered species among cetaceans.

Elk:

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Elk; ; David's deer

The only species of the genus Elk in the family Cervidae. The head is like a horse, the horn is like a deer, the hoof is like an ox, and the tail is like a donkey. Body length is about 2 meters, shoulder height 1 meter or more, tail length, tail hanging to ankle; Hair is taupe in winter and reddish brown in summer. There are 1 dark brown longitudinal stripes extending to the front of the back and dark brown long hair under the neck. The male has horns and is divided into two branches, each branch has two branches, and each branch is divided into some small branches. It is a special animal in China.

Love the water, an elk, is good at swimming. Because the hoof is wide, the lateral hoof can also land, which is suitable for activities in snow mud. Feed on grass, leaves and aquatic plants. Estrus from June to August. The pregnancy is about 10 month, and the baby will be born around May of the following year.

There are elk bones in the animal bones unearthed in Yin Ruins, indicating that wild elk once lived in the Yellow River valley 3000 years ago and later became extinct. The existing elk are only captive populations, and the number is very small, most of which are in Britain. China was raised in Beijing Nanyuan in Qing Dynasty, but it was destroyed by Eight-Nation Alliance, and only a few people lived abroad. After the founding of the People's Republic of China, dozens of them were imported from abroad and kept in zoos such as Elk Garden in Beijing and Jiangsu.

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Protection status: extremely dangerous

Boundary: animals in the animal kingdom

Door: Chordata, Chordata.

Class: mammals

Objective: Artiodactyla in Artiodactyla.

Family: Cervidae

Genus: Elk

Species: Elk

Scientific elk

(Milne Edwards, 1866)

Elk belongs to the family Cervidae. Because its head and face are like horses, horns like deer, hooves like cows and tails like donkeys, it is also called four elephants. It is native to the marshes in the middle and lower reaches of the Yangtze River in China. It feeds on grass and aquatic plants, and sometimes it eats seaweed in the sea. It is two meters long and weighs 300 kilograms. 1000 -3000 years ago was quite prosperous, with the middle and lower reaches of the Yangtze River as the center and distributed from the west to the north of Shanxi Province. Later, due to natural climate change and human hunting, it was almost extinct in the late Han Dynasty. In the Yuan Dynasty, Mongolian soldiers captured the remaining elk and transported them to the north for hunting. Extinct in nature. By the19th century, there were only about 200-300 groups left in Nanhaizi Royal Hunt Park. 1866 was discovered by French missionary Father David and ordered Latin species. Many countries use bribery, theft and other means to get some for their national zoos. 1894, the Yongding River flooded and destroyed the walls of the Royal Hunting Garden. The remaining elk escaped, were hunted by Hungry and Eight-Nation Alliance, and then disappeared in China.

1898 1 1 Duke Beffort of England spent a lot of money to buy back all 18 elk scattered in Paris, Antwerp, Berlin and Cologne and put them in Wubangs Manor. By 1983, 255 milu deer have been bred. In order to prevent their extinction, they began to evacuate to zoos in various countries.

Under the coordination of the World Animal Protection Organization, the British government decided to provide free population to China, and let the elk return to their hometown. 1985, 22 were released to the former Nanhaizi Royal Hunt Park in Daxing District, Beijing, and an elk park in the reserve was established. 1986 provided another 39, which were kept in the original elk producing area of Dafeng City, Jiangsu Province, and a nature reserve was established. 1987 and 18.

After the reunification, elk breed quite quickly. 1994, the government of China established the third elk reserve in Tianezhou, Shishou City, Hubei Province, and moved 64 elk from Dafeng. At present, the total number of milu deer in China has reached 1320. But it is still an endangered species. There are no more than 2000 in the world.

supplement

Lipotesvexillifer Miller

Baiji Dolphin, also known as Baiji Dolphin, is commonly known as Baiji Dolphin, Baiji Dolphin and Ma Jiang. Its English name is Yangtze Dolphin, belonging to url] Cetacea.

The distinctive feature is that the snout is long and narrow, about 300 mm long. The forehead is round and high. The dorsal fin is triangular, located in 3/5 of the body, and has a low skin ridge connected with the caudal fin. There is a breathing hole on the left side of the head that can be opened and closed freely. The caudal fin is horizontal, concave to the edge and crescent-shaped. The population of baiji dolphin is very small, which is a rare aquatic animal endemic to China and needs to be protected urgently.

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Baiji dolphin is a unique mammal in China and the least animal in the world. Because it is a rare animal unique to China, it is called "the giant panda in the water". It is a national first-class protected animal. At present, it is only distributed in the reach of about 1600 km from Zhicheng, Hubei Province to the Yangtze River estuary in the middle and lower reaches of the Yangtze River. They feed on fish and move in groups, with 2 ~ 3 heads in small groups and 0 ~/0 ~/0/6 heads in large groups. In recent years, the population has decreased rapidly. According to reports, there were more than 400 in the early 1980 s and it was reduced to 300 in the mid-1980 s. 1990 has more than 200 animals, 1993 has more than 130 animals, and 1995 has less than 100 animals, which are listed as the first-class endangered animals in the world.

The Three Gorges Project is built at the outlet of the upper reaches of the Yangtze River, which is not in the habitat of the baiji and will not directly endanger their survival. However, the regulation of the hydrological situation of the Yangtze River by the Three Gorges Project may have an impact on its habitat. Baiji dolphin mainly inhabits the large backwater area of the curved reach and the curved Fenhan reach. When the river regime changes and the large backwater area moves, the baiji also moves, and the migration distance is related to the length of the large backwater area. The scouring of the river bed by the clear water discharged from the Three Gorges Reservoir may change the backwater area and make the habitat of Baiji dolphin migrate. According to the most serious estimate, the habitat of Baiji dolphin may move down more than 65,438+050km, which is less than the current distribution range of 65,438+0/65,438+00. In addition, after the improvement of shipping conditions, the number of sailing vessels will increase, which may increase the probability of accidental death of baiji. In order to protect this endangered precious aquatic animal, the state has established Baiji dolphin nature reserves in Luoshan to Xintankou in the middle reaches of the Yangtze River, the old waterway of Shishou Swan Island and Tongling in the lower reaches of the Yangtze River.

Taxonomic status: Mammals, Cetaceans, Freshwater Dolphins.

Appearance: 2 meters in length and weighing 100 ~ 200 kg. The snout is long and narrow, about 30 cm, with 130 conical teeth densely arranged on both sides of the upper and lower jaws, and the forehead is rounded. The skin is delicate and smooth, the back is light gray-blue, the abdomen is clean and white, the body surface is streamlined, the forelimbs are flippers, and the dorsal fins are triangular. Hindlimb degeneration, tail

The end is flat and divided into two leaves in a crescent shape. There is a long and round hollow nose or breathing hole on the upper left of the head. The eyes are only the size of mung beans, which have degenerated and are located behind and above the corners of the mouth. There is only a hole in the ear the size of a needle eye, which is located behind the eye, and the external auditory canal has disappeared.

Distribution: It is distributed in the Yangtze River in China, from below the Huangling Temple of the Three Gorges to the Yangtze River estuary, as well as large lakes and tributaries along the Yangtze River.

Living habits: sight, hearing and smell have all deteriorated. Contact with the same kind in the water, avoid enemy damage, identify objects, detect food, etc. , relying entirely on sonar signals. Mild temperament. It feeds on freshwater fish such as carp, silver carp, grass carp, herring, snapper, red-eyed trout and catfish. There are two estrus periods every year, March-May and 8- 10. The gestation period is 10 ~ 1 1 month. Each fetus is only born 1 baby.

Living conditions: In 1950s, a large number of baiji were still seen in the Yangtze River, but since then, the number of baiji has dropped sharply and disappeared in lakes and tributaries along the Yangtze River. The number of individuals in the Yangtze River is less than 100, leaving only a section from Zhicheng in the middle reaches of the Yangtze River to Nanjing. It is listed as 1 protected animal in the List of National Key Protected Wild Animals in China. It is listed as an endangered species in the Red Book of Endangered Animals in China, and it is listed in the appendix of Washington Convention: A Class of Protected Animals.

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Also known as "freshwater dolphins". Mammals, baiji. Rare animals endemic to China. Body length 1? 5~2? 5 meters. The kiss is long, with about 130 teeth. The back of the body is light blue-gray and the abdomen is white. Feed on fish. Mainly inhabiting Dongting Lake and the middle and lower reaches of the Yangtze River. It is a national first-class protected animal.

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White dolphin {{#if:PE|

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White dolphin (scientific name:

It is the smallest of the four existing freshwater dolphins in the world, and it is a national first-class wild protected animal in China < Ref name= "Hu Benzheng"/>. 1996 is listed as one of the most endangered 12 species by IUCN, and also listed in the International Red Book of Endangered Species, the International Convention on Endangered Species (Appendix I) and the National Endangered Species Act of the United States.

[Edit] Naming

Note: This entry contains a new version of Unicode hieroglyphics {{#if:4C5C|:? }}。 If your computer doesn't have -{zh-cn: support; Support zh-tw:}- Related characters will display errors as spaces, question marks or squares. See Wikipedia: Unicode Extended Chinese Characters.

The baiji dolphin was first recorded in the dictionary Erya in Qin and Han Dynasties, and this animal was named "jí". This is because I didn't know much about cetacean aquatic mammals at that time, so I mistakenly classified this mackerel as a fish and used the word "fish" when I coined it. Fishermen and people along the Yangtze River call it "Jiang Pig". It is estimated that there used to be as many as 5,000 heads in China, known as the goddess of the Yangtze River and the "Mermaid of the Yangtze River". Template: quote news & lt/ref & gt；; & ltref & gt template: quote news & lt/ref > & ltRef name= "Hu Benzheng" />. . Guo Pu, a native of Jin Dynasty, made a more detailed comment on the life habits and morphological characteristics of baiji in Er Ya Zhu, and correctly classified baiji into fish for the first time:

Hehe is also a genus that looks like a sturgeon and a fish. The beak is small, sharp and long, the teeth are hairy and the nose is on the forehead. Can be quiet, less meat and more cream, viviparous, healthy and fine fish, more than a foot big. There are many in the river. & ltref & gt Guo Pu, er ya note.

In the Northern Song Dynasty, Confucius wrote poems about finless dolphins. The "mackerel" in the poem is a baiji dolphin, and it is pointed out that it is not the same species as the finless porpoise:

Black finless porpoise and white mackerel. It seems that the name is different, and there are big fish in the same room.

Besides, it is called Green Chicken in Anhui, China, Moby Dick and Ma Jiang in Jiangsu. Fishermen in the middle and lower reaches of the Yangtze River generally call it Moby Dick, which means its skin color is lighter than that of finless porpoise. & ltRef name= "Investigation on the distribution of white dolphins"/>.

19 14 American young adventurer Hoy (

19 18, Miller published his research summary in a series of magazines of Smith Institute. His research paper is entitled "A new species of freshwater dolphins in China" < ref name="Miller "> Template: citing journal ; Confirmed that the white dolphin is a unique new animal species, and set the Latin scientific name: "

The word "Mi Gu" in Ci Hai published by China refers to the white dolphin. But because the word "Mo" is not in the general dictionary, people seldom use it. 1955 published the name of the vertebrate called baiji. But the fin of baiji is bluish gray or gray, which is easily misunderstood as baiji, a name that has never been used before. At the end of1970s, biologists studying baiji proposed that it should be called baiji.

[edit] classification

There has been some controversy about the scientific classification of baiji, mainly on which family baiji belongs. For example, the International Red Book on Endangered Species classifies it as a lipid family.

19 18 After comparing the bones of Baiji dolphin and sub-pufferfish, Miller thought that they were close relatives, and classified Baiji dolphin into sub-pufferfish < ref name = "Miller "/& gt；; . Most biologists also support his conclusion template: citing the journal ZH ; . From 65438 to 0979, China biologist Zhou Guangya and others denied Miller's conclusion after comparing the bones of Baiji dolphin and other freshwater dolphins, and established the template of < ref>: citing the journal zh & lt/ref & gt；; And has been recognized by some other scholars.

Evolutionary history

According to paleontologists' fossil research on the template, in fact, Baiji dolphin appeared in the Yangtze River basin in Miocene and Pliocene of Tertiary. 198 1 In September, Chinese geologists discovered a fossil fragment of mandible in Guiping, Guangxi. This mandible fossil belongs to an ancient baiji, known as the original baiji. Fossils record the ancient characters of the original baiji about 20 million years ago, which has not changed much compared with today's baiji. The baiji still retains many primitive baiji bones. The slow evolution of Baiji dolphin may be due to the past survival competition or less environmental changes, thus retaining the ancient appearance of its ancestors, so it is called "living fossil" and "giant panda in water" < Ref name= "Hu Benzheng"/>. If it is not a big ecological change, it will not be extinct.

[edit] distribution

Baiji dolphin was widely distributed in the Yangtze River basin in history. From 35km upstream of Gezhouba in Yichang, the Three Gorges area to the Yangtze River estuary near Shanghai, including Dongting Lake and Poyang Lake, there are baiji in the river with a total length of about 65,438+0,700km < Ref name= "Baiji Dolphin Distribution Survey"/>.

However, due to the long-term influence of human activities, its population and distribution area are gradually shrinking. Today, there are more than 300 million people living in the Yangtze River valley, equivalent to 5% of the world. Their activities along the river formed the first reason for the decline in the number of baiji. In the 20th century, 92% of the specimens collected by people came from man-made deaths. By 1990, the baiji in Dongting Lake and Poyang Lake had been extinct. The upper limit of its distribution in the Yangtze River has also moved to Jingzhou in the lower reaches of Gezhouba 170 km. Its lower limit has been seriously lowered, and it is hard to find near Nanjing. During the observation period from 1997 to 1999, it was never found below Jiangyin in the lower reaches of Nanjing.

In several observations from 2000 to 2004, its distribution was mainly limited to the Dongting Lake to Tongling section of the Yangtze River basin. Among them, it is mainly concentrated in Tongling section, Poyang Lake section and Honghu section. The last time baiji was found in the wild was a stranded corpse found in Nanjing section of the Yangtze River in 2004.

Photo: Diqu.png Baiqitun Branch

Satellite map of the middle and lower reaches of the Yangtze River, showing the physiological structure of Baiji dolphin habitat [edit]

[Edit] External Type

Baiji dolphin has a streamlined body and a spindle-shaped trunk. The adult baiji is about 1.4 to 2.5 meters long and weighs about 135 to 230 kilograms. Males are slightly smaller than females. As of 2006, the largest female was found to be 2.53 meters long and weighed 237 kilograms. The largest male found is 2. 16 m long and weighs 125 kg.

The skin of baiji dolphin is smooth and elastic, which has the same function as nylon fabric of competitive swimsuit. It can reduce the turbulence around the body when swimming fast in the water. Its tail fin is divided into two forks, flat and wide, parallel to the water surface, and can push the body forward when swinging up and down. The pectoral fins on both sides are flat palms. The dorsal fin growing in the middle of the back is a low isosceles triangle.

Four fins provide direction and balance control for the baiji, with smooth and elastic skin and streamlined body. The speed of the baiji can reach 80 kilometers per hour when avoiding danger. However, its swimming speed is generally only 7.5-9.7 km downstream and 2.7-4.9 km upstream, which is the best swimming speed that the biological energy in Baiji dolphin can maintain < Ref name= "Hu Benzheng"/>.

[Edit] Body color

The newborn larvae are slightly darker in color, and the adult baiji generally has a light bluish gray back and a clean and white abdomen. The upper and lower surfaces of horizontally extending flippers and caudal fins are the same color as the back and ventral surfaces, respectively, so the color distribution is just in line with the environmental color. Looking down from the water, the bluish gray on the back is mixed with the river. Looking up from underwater, the white abdomen is similar to the strong light reflected in the water. This color, which is difficult for other animals to recognize, is called anti-shading and protective color, so that the baiji will not be noticed when it approaches the enemy or prey.

[Editor] Tooth Structure and Breathing Hole

The white dolphin's snout is long and narrow, beak-shaped, extending forward about 30 cm. Its teeth are conical and carefully arranged on both sides of the mandible, which is almost equal in length from top to bottom. There are 3 1 to 36 teeth on each side, and there are about 130 teeth of the same type.

The breathing hole (or "nostril") of Baiji dolphin is located at the upper left of the head, small and long, and the edge of the hole has a flap that can be opened and closed freely. When you come out of the water, your nostrils are open. After breathing, you will close your mouth and dive. The way of daily activities is to alternate diving, swimming and breathing. Usually, every 10 to 30 seconds, it will come out of the water to take a breath, and when it takes a breath, it will make a "poop-poop" sound. The baiji can stay underwater for more than 200 seconds without breathing under special circumstances of being frightened or feeling dangerous. Under normal circumstances, the respiratory rate is 109- 150 beats/hour.

Sense and sound structure

The eyes of the white dolphin are located behind the corners of the mouth, as small as mung beans. Because baiji has lived in the turbid water of the Yangtze River for a long time, its vision has been seriously degraded. The outer ear has disappeared, and the ear hole is still there, just as small as the eye of a needle, and it is blocked. Although the white dolphin has a small ear hole, its hearing is very sensitive.

The forehead of the white dolphin is round and protrudes forward. Similar in shape to the focusing lens in a camera, it is called the "anterior protrusion" and is the most important part of the vocal organs of baiji. The upper respiratory tract of baiji has a throat shaped like a goose's head, but because it lives in water and makes sounds by water, it doesn't have the vocal cords needed by land animals to make sounds in the air. In addition, there are three pairs of unique airbags in the upper respiratory tract, which may be the template of its vocal parts: Cite journal zh & lt/ref & gt；; .

Through a special hydrophone, you can hear dozens of different sounds, such as "answer" and "quack" from the baiji. Frequent sounds can be divided into two categories: one is the "tick-tock" sound with the frequency of 8 ~ 160 kHz, which plays the role of detecting targets. The other is whistle, the frequency is stable at 6 kHz, which is the communication signal between baiji dolphins. This kind of signal has good diffraction and conduction ability, and is suitable for the Yangtze River waters with more sediment.

In water, baiji mainly uses the echolocation method of transmitting sonar and receiving signals to identify objects. The sounds are usually made in pairs. After the sound is emitted, you will wait for the echo quietly, so as to distinguish the distance and size between yourself and the obstacle that produces the echo and consider whether to swim to the target. The wider the wavelength, the bigger the object, the stronger the signal and the closer the object is. At this time, it will send out a pair of new signals, and then quietly wait for an answer. After receiving the second echo, it can analyze the swimming direction and speed of the target. The denser and closer the echo is, the thinner and farther it is. In this way, the baiji uses its unique sonar system to catch food in the dirty river.

[Editor] Brain activity

The brain area of baiji dolphin is larger than that of dolphins. The weight of the brain accounts for about 0.5% of the total weight. On average, the brain of a 95 kg male dolphin weighs 470 grams, which is close to that of gorillas and chimpanzees. Even some scholars think that baiji is smarter than chimpanzees or gibbons.

Mammalian brains need to go to sleep after a period of use in order to work normally after awakening. Cetacean aquatic animals, including baiji, have a unique brain system, which can make half of the brain rest and the other half awake. The brain of the adult baiji is half asleep and half awake for 7 to 8 hours every day (similar to the sleeping habits of adults), and the whole brain is awake at other times. Half asleep and half awake, the baiji will keep floating on the water at the speed of 1 to 5 kilometers per hour. Like other mammals, baiji can dream, and its characteristic is that its brain can be half awake and half dreaming.

As a mammal, baiji, like humans, needs to continuously supply oxygen to the blood in the body. Unlike terrestrial mammals, cetaceans living in water can control involuntary breathing through the cerebellum, and all their breathing is spontaneous breathing that requires brain response. Therefore, breathing must be done in a conscious state. If a cetacean loses consciousness due to shock and injury, it will sink to the bottom of the water. Dolphins will enter a state of brain death after the remaining oxygen in their blood is exhausted. Therefore, drowning is a normal way of death for the elderly and frail baiji.

[Editor] Living habits

Baiji dolphin is timid and easily frightened, generally far from ships, and it is difficult for humans to get close. In addition, its population is small and its active area is relatively wide, so the research on the living habits of baiji in the wild is very limited.

Baiji dolphins are generally gregarious, but the gregarious characteristics are far less obvious than those of dolphins belonging to cetaceans. The number of single population is generally around 3 ~ 4, and most of them are 9 ~ 16. However, it is often found that individual baiji act alone. Social baiji dolphins usually have an adult or older individual dolphin leading the way, with a young dolphin in the middle and a young dolphin behind. Baiji dolphin often moves at the intersection of rivers, especially in the shallow water area where rivers are alluvial, and it is common to play with finless porpoises. Like other finless porpoises, baiji usually moves during the day, especially in the morning and afternoon. Often a few baiji dolphins are lined up in a row. In shallow water, they frequently come out for air at intervals of 10 to 30 seconds, making rapid progress, with the fastest speed reaching 80 kilometers per hour. At other times, the baiji is relatively quiet, usually swimming slowly in deep water, and the interval of air exchange becomes longer, up to 200 seconds. At night, the baiji often rest in the deep whirlpool, sometimes staying in the same place for 5 to 6 hours.

Baiji dolphin is a carnivore, which can prey on many kinds of freshwater fish in the middle and lower reaches of the Yangtze River, but it is mainly small fish with a body length of less than 6.5 cm. The main prey are grass carp, herring, bighead carp and silver carp. The gregarious baiji dolphins prey collectively. It bit the head of a small fish near the epiphysis with its teeth, then swallowed it, swallowed it directly, without chewing. Eat a lot, and the daily food intake can account for 10% to 12% of the total weight.

[Edit] Copy

Like mammals, baiji is viviparous. Life expectancy is about 30 years old. According to the anatomical research results, the male baiji is young at 0-4 years old, sexually mature at 4 years old, mature at 4- 12 years old, and adult at 12-20 years old. On the other hand, females are relatively late and reach sexual maturity at the age of 6. Male estrus is usually twice a year, from March to June and 10- 12. During this period, the male animal's skin color is purple (red+gray), and he often explodes impatiently for air; Every other year from February to April, the pregnancy rate of females reaches the highest point.

The natural reproduction rate of baiji is lower than that of other cetaceans. In the wild, the male-female ratio of adult baiji is 1: 1. Only 30% of females are mature, and only 30% of mature individuals can get pregnant.

In the artificial breeding environment, due to long-term solitude, the male baiji will masturbate by sticking his abdomen to the bottom of the pool, sticking to the wall of the pool and exposing his penis during estrus. The results of field observation show that the male dolphin first lies on the back of the female dolphin, then the female dolphin leans over, and the male and female dolphins lean over, with their heads, bellies and tails facing each other, and at the same time dive underwater to breathe < ref> template: cite journal zh & lt/ref & gt；; . However, field observation is limited by natural conditions, so it is difficult to distinguish between male and female. Some scholars have observed the sexual masturbation behavior of male baiji in artificial breeding environment, pointing out that male baiji probably mated with female dolphins, but it is unknown whether it has changed due to the influence of artificial environment. Ref> template: reference journal z