Introduction to rare animals in China

Chinese name: giant salamander

Latin scientific name: Andrias davidianus

Common names: salamander, mermaid, baby fish, pike, cod, foot fish, cry fish, Dachshund

National key protected animal level: Level 2

World Conservation Union (IUCN): Undecided (I)

Endemic species: Yes

Endangerment level: Endangered

Convention on International Trade in Endangered Species of Fauna and Flora (CITES): Appendix I

Ecological environment: Mountain streams or pools

Upper altitude limit: 2800 Lower altitude limit: 100

Threat factors: Hunted for trade, hunted as medicinal ingredients, hunted for food, migratory trips are cut off, environmental pollution

Protection Measures: artificial breeding, artificial breeding, national level, existing protected areas

Domestic distribution: Ningxia, Hebei, Shanxi, Jiangsu, Zhejiang, Anhui, Fujian, Jiangxi, Henan, Hubei, Hunan, Guangdong, Guangxi, Sichuan, Guizhou, Yunnan, Shaanxi, Gansu, Qinghai

[Edit this paragraph] Classification status

Animal Kingdom Fauna → Chordata CHORDATA → Vertebrata Vertebrata → Amphibian Class Amphibia → Caudata → Cryptobranchoidea → Cryptobrachidae → Andrias → Andrias davidianus

[Edit this paragraph] Morphological characteristics

Existing The largest of the tail order, it is the largest among amphibians, with a total length of 1 to 1.5 meters, and the heaviest one can weigh over 100 kilograms. Its appearance is somewhat similar to a lizard, but it is fatter and flatter in comparison. . Giant salamanders inhabit streams in mountainous areas and live in caves with clear water, low sand content, fast currents, and backflow water. The giant salamander has a flat, blunt head, a large mouth, underdeveloped eyes and no eyelids. The front part of the body is flat, and gradually turns to side flatness towards the tail. There are obvious skin folds on both sides of the body, the limbs are short and flat, the fingers and toes are five in front and four in back, and are slightly webbed. The tail is round, with fins on the top and bottom of the tail. The body surface is smooth and covered with mucus. The back of the body is mixed with black and brown-red, and the ventral surface is light in color.

[Edit this paragraph] Living habits

It is not good at hunting. It just hides among the rocks at the mouth of the beach and makes a sudden attack when it finds prey passing by. Because the teeth in its mouth are sharp and dense, it is difficult for prey to escape after entering its mouth. Its teeth cannot chew, it just opens its mouth to swallow the food whole, and then slowly digests it in its stomach. The giant salamander has a strong ability to withstand hunger and will not starve to death even if it does not eat for two or three years. It can also overeat, and a full meal can increase one-fifth of body weight. When food is scarce, cannibalism will also occur, and even eggs will be used to satisfy hunger. It likes to eat aquatic animals such as fish, crabs, shrimps, frogs and snakes.

[Edit this paragraph] Distribution status

Except for Xinjiang, Tibet, Inner Mongolia, Jilin, Liaoning, and Taiwan, which have not been reported, the Chinese giant salamander is distributed in other provinces and regions, mainly produced in In the mountain streams and tributaries of the middle and upper reaches of the Yangtze River, Yellow River and Pearl River, they usually live in the rock crevices of the mountain streams, and the caves are located below the water surface. The cry is also like the cry of a baby, so it is commonly known as "Baby Fish".

The natural distribution of the origin of Chinese giant salamanders is mainly concentrated in four major regions in my country: first, Zhangjiajie and Xiangxi Autonomous Prefecture in Hunan; second, Fangxian and Shennongjia, Hubei; third, Hanzhong, Shaanxi; fourth, Zunyi, Guizhou and Yibin, Sichuan , Wenxing and other places. Others are scattered in Hefeng and Enshi in Hubei, Jing'an in Jiangxi, Liuzhou and Yulin in Guangxi, Wenxian in Gansu, Lushi County and Hao County in Henan and other places. According to statistics, the natural resource reserves of giant salamanders are about 90,000, with the majority of resources in hilly and mountainous areas. In economically developed areas, due to the intensification of industrial pollution, resources are even more scarce.

[Edit this paragraph] Reproductive habits

They lay eggs between July and August every year, each laying more than 300 eggs. After the female salamander lays eggs, the "mission" ends . The male salamander carries the egg belt around his back, and it hatches after 2 to 3 weeks. From then on, the male salamander will take on all the tasks of incubating the eggs until the baby "salamfish" disperse and live 15-40 days later.

[Edit this paragraph] Reasons for being endangered

Because its meat is tender and delicious, it has been hunted in large numbers for a long time. The number of various production areas has dropped sharply, and some production areas are on the verge of extinction.

The current reality is that the giant salamander, a precious wild resource, is mainly due to human factors, especially the loss of living environment, habitat destruction and over-exploitation, which has posed a serious threat to the survival of the giant salamander, leading to a sharp decline in the population. Its distribution area has shrunk exponentially and it is in an endangered state.

[Edit this paragraph] Breeding status

Wild resources of Chinese giant salamander. Some people estimate that the total stocking volume in the country is 50,000. The number of real wild giant salamanders still in nature may not reach 50,000. Of course, a more realistic number needs to be evaluated through in-depth investigation and research; the artificial breeding of giant salamanders is reproduced every year across the country. The quantity, some people report is 100,000, which may actually be insufficient.

According to the main population density in the country, the number is around 80,000.

We must attach great importance to saving and protecting giant salamander germplasm resources, because only with "seeds" can we see seedlings. Otherwise, it will become water without a source and a tree without roots. In other words, giant salamander seed breeding must first start from the source of germplasm resources, and the Chinese giant salamander germplasm resource bank and Chinese giant salamander original species breeding base must be quickly established to completely solve the "source" problem of giant salamander seed breeding.

China's first giant salamander ecological park has recently started construction in the Sanzhalun National Demonstration Forest Park in Jing'an County, Jiangxi Province. The project has a total investment of 15 million yuan and covers an area of ​​80 hectares. It is a key construction project of the Ministry of Agriculture.

The first phase of the project will be completed in October this year, with the ability to breed 50,000 giant salamanders and rescue 1,000 giant salamanders each year. The ecological park integrates giant salamander resource protection, breeding and viewing, tourism and leisure, cultural exchange and development and utilization, setting a precedent for comprehensive protection, development and utilization of giant salamander resources in the country.

Jing'an County is the main producing area of ​​Chinese giant salamander resources and is the unique "Hometown of Chinese Giant Salamander". The county was the first in the country to issue a notice to protect giant salamanders, the first to establish a giant salamander nature reserve, the first to establish a specialized giant salamander research institute, and the first to artificially breed first, second and third generation giant salamanders. In 2001, Jing'an designated the giant salamander as the county mascot and protected it.

[Edit this paragraph] Conservation value

The giant salamander is a unique species in my country. Because its cry is similar to the cry of a baby, it is commonly known as the "salam fish".

The giant salamander has a special heart structure and has some reptilian characteristics, which has important research value.

The Chinese giant salamander is a Category II protected animal with high economic value and the prospect of extensive development and utilization in food, health care, medicine, ornamental and other aspects, so it has attracted much attention from all walks of life.

Giant salamander is a traditional and valuable medicinal animal. Modern clinical observations have found that giant salamander has the effects of nourishing yin and kidneys, nourishing blood and promoting qi, and has significant effects on anemia, cholera, malaria, etc. At the same time, giant salamander is also an economic animal with extremely high edible value. Its meat is tender, unique in flavor, and has extremely high nutritional value. Its meat protein contains 17 kinds of amino acids, 8 of which are essential amino acids for the human body.

[Edit this paragraph] Artificial breeding

1. Design and construction of giant salamander breeding ponds

In nature, giant salamanders live in mountain streams at an altitude of 300 to 800 meters. The artificial giant salamander breeding ponds are afraid of wind, prefer quietness and fear of surprises, and prefer cleanliness and fear of dirt. It is best to imitate the natural living conditions of giant salamanders when constructing artificial breeding ponds.

1.1 Selection requirements for breeding sites

1.1.1 Water resources requirements

According to the analysis results of water samples taken by our institute for many years, the water requirements of giant salamander breeding are The overall requirements are: sufficient water source, non-toxic and harmless, and in line with fishery water standards. Specifically, in terms of water sources, it is better to use clear, cool, flowing water such as mountain stream water, reservoir water, and groundwater, which can achieve free drainage and irrigation; in terms of water temperature, it should be strictly controlled within 0 to 28°C, preferably 10 to 22°C. ; In terms of water quality, it requires rich dissolved oxygen, above 3.5 mg/L, and a pH value of 6.5 to 7.5. The total hardness, total alkalinity, chloride, sulfate, silicate, ammonia nitrogen, etc. in the water cannot exceed the fishery water standards.

1.1.2 Environmental requirements

The environment around the breeding pond is required to be quiet, cool, and fresh. It is better to be surrounded by mountains, lush trees, sparsely populated, and relatively independent. In addition, It requires convenient transportation and abundant local bait resources such as fish, shrimp, crab or animal offal.

1.2 Design and construction of breeding farms

Giant salamanders grow in obvious stages and undergo metamorphosis. The breeding ponds for artificial breeding of giant salamanders must be designed and constructed in stages. The area of ​​the breeding pond should depend on the size of the giant salamander. The juvenile salamander pond (tadpole stage within 1 age) is 0.5 to 1 square meters, the young salamander pond (young salamander stage 1 to 2 years old) is 1 to 2 square meters, and the adult salamander pond ( The adult salamander stage (2nd to 4th age) is 2 to 4 square meters, and the parent salamander pool (4th age and above) is about 5 square meters. Giant salamander breeding ponds at each stage should preferably be rectangular or oval in shape, with an aspect ratio of 3:2. The height should be two to three times the full length of the giant salamander being cultured. The surroundings and bottom of the breeding farm pond should be smooth, and the top should be smooth. Build anti-escape facilities or cover with anti-escape nets. Multiple caves can be designed in the pond to facilitate the giant salamanders to hide. Each breeding pond should build independent drainage and irrigation facilities so that the water level can be effectively adjusted, water can flow in and out freely, and sewage can be discharged conveniently. The entire breeding farm should have complete facilities to prevent giant salamanders from escaping, stealing and harming them.

2. Giant salamander seed stocking and seed identification

2.1 Disinfection of breeding ponds

Newly built breeding ponds, especially cement ponds, must be soaked for two For more than 1 month, the seedlings can be released after the alkalinity disappears. The original breeding pond must be disinfected. Disinfection drugs generally use 1PPM bleaching powder or 0.5PPM 90% crystalline trichlorfon to kill harmful organisms such as bacteria or parasites. Then rinse with clean water and inject new water before stocking the seedlings. .

2.2 Disinfection of salamander species

In order to prevent salamander species from bringing pathogenic microorganisms into the breeding pond, all stocked salamander species should be treated with 0.2g of furans or methylene per cubic meter of water. Mix 0.5g of base with water and soak for 5 minutes, then gently put the potion and salamander seeds into the breeding pond.

2.3 Seedling identification

2.3.1 The difference between giant salamander seedlings and other seedlings

Among amphibians. Among the anurans, species such as Salamanderidae, Salamanderidae, and Caveridae are very similar to giant salamanders. The most important thing that distinguishes them is the comparison of their morphological characteristics, which mainly include the following three points: Cryptobranchidae (giant salamanders), Salamanderidae , Comparison of morphological characteristics of Salamanderidae

2.3.2 Identification of the physical quality of giant salamander seedlings The physical quality of giant salamander seedlings is directly related to the success of breeding. High-quality giant salamander seedlings should have a strong body, thick muscles, no scars and parasites on the body surface, and intact external gills without lesions before metamorphosis. On the contrary, it is inferior salamander seedlings.

2.4 Stocking density

The stocking density of giant salamander breeding ponds depends on the specifications of the giant salamanders and the water source, water body, bait and other factors of the farm. Under normal circumstances, considering that giant salamanders have a small activity range and weak feeding ability during the seedling stage, the stocking density can be appropriately high to facilitate centralized management and breeding. In the adult stage, the stocking density of giant salamanders should be small considering their large activity range, strong feeding ability, and mutual aggression. Our many years of breeding practice believe that the stocking density is 60 to 100 fish/square meter in the seedling stage and 5 to 20 fish/square meter in the adult stage. When stocking, the specifications are required to be as neat as possible, and the difference between individuals should not be more than 0.5 times.

3. Breeding management

3.1 Feeding

The best feed for giant salamander is fresh fish, shrimp, crab, frog and animal offal. The same as feeding fish breeding bait, the "four fixes" should be achieved, namely "timing, positioning, quality and quantity". Timing, according to the activity status of the giant salamander, feeding is mostly carried out in the evening; positioning, the bait should be placed near the giant salamander cave to facilitate the lazy giant salamander to feed; qualitative, the giant salamander has strict requirements on the quality of the bait, requires freshness, and the bait The species should not change too much to prevent giant salamanders from refusing to eat; quantitatively, giant salamanders are gluttonous, and the feeding amount should be from small to large, step by step, generally 10 to 15% of body weight. The specific feeding should also be based on water temperature and weather conditions. , giant salamander individuals and other conditions, make appropriate adjustments. In addition, when feeding giant salamanders with bait, try to keep the giant salamanders from being frightened to prevent them from vomiting food.

3.2 Adjust water quality

When breeding giant salamanders, the water quality in the giant salamander pond should always be kept clean and pollution-free, with high water transparency, high dissolved oxygen, and a pH value between 6.8 and 7.8. In the actual breeding process, residual bait and excrement should be removed in time, quicklime should be used regularly to adjust the water quality, and the pool water should be kept flowing for a long time.

3.3 Adjust water temperature and light

Giant salamanders have strict requirements on water temperature. Exceeding their tolerance will cause giant salamanders to hibernate or aestivate. In hot summers and cold winters, cooling must be taken Or take warming measures to ensure that giant salamanders have a suitable water temperature environment for their growth. In addition, giant salamanders are photophobic, so farms should take measures to avoid strong sunlight. When inspecting at night, strong light should not be used.

3.4 Anti-escape and anti-theft

The giant salamander has a very strong ability to escape. It can move quickly on land or in water, and can climb high and carry heavy loads. It will escape if it is not careful. Always be careful to avoid escaping, especially when it rains heavily. All water inlets and outlets and land passages in the breeding pond and the entire breeding farm must be equipped with anti-escape facilities. Giant salamanders have high economic value, and care must be taken to prevent theft by criminals during the breeding process.

4. Disease prevention and control

In the artificial breeding environment of giant salamanders, due to the influence of environment, food, density, etc., the incidence and mortality rate of artificially cultured giant salamanders are dozens of times higher than those of wild giant salamanders. As mentioned above, in order to improve the survival rate of giant salamander culture, we must strengthen daily management and focus on prevention to ensure the success of giant salamander breeding.

4. Breeding conditions:

Can be cultured both indoors and outdoors. There are specially built breeding ponds in the open air outdoors, and breeding ponds transformed from various idle facilities indoors. The breeding pond only needs to be safe and secure without water leakage, and maintain running water or be equipped with an aerator. The size of indoor breeding ponds can range from 1 square meter to dozens of square meters. The breeding pond needs to be soaked in water for 1 month before stocking to keep the pH value below 6.4. Generally, strong light is not required and only low light or no light can be maintained.

5. Stocking of seedlings:

Giant salamander breeding generally introduces young salamanders above 10 cm, and about 20 salamanders can be released per square meter of water surface. Before stocking the seedlings, the breeding ground should be soaked in 2 mg/L copper sulfate for 5 hours to disinfect, and the salamander body should be bathed in 5% sodium chloride for 10 minutes. In advance, a cave was built with granite in the pond and aquatic plants were placed for the giant salamander to hide.

6. Feeding:

The breeding pond is equipped with a bait table, which is slightly higher than the water surface. When feeding feed, it is better to use natural feed, mainly including plankton, insects, meat, fish, shellfish, etc. Feed once every morning and evening, preferably before 7:30 in the morning and before 10:30 in the evening. When feeding, you should first clean up the remaining bait from the previous time. The feeding amount is 5-10% of body weight.

When the water temperature is 16-23°C, the amount of feeding should be increased, and the frequency and time can remain unchanged.

7. Daily management.

Daily management of giant salamanders is simple but important. Keep three things in mind when feeding: timing, point, and quantity. It is important to understand the ecological habits of giant salamanders. Giant salamanders like silence and are afraid of noise, like clear water and are afraid of muddy water, and like darkness and are afraid of strong light. We should try our best to take care of these habits of giant salamanders in breeding. In addition, disinfect the salamander body and breeding pond regularly to prevent diseases, pay attention to changes in water temperature, control the water temperature not to exceed 26°C in summer to prevent "aestivation", and prevent the water temperature from falling below freezing temperature in winter.

[Edit this paragraph] Prevention and treatment of tail rot disease

1. Causes of tail rot disease in giant salamanders

(1) Impact of water quality

< p> Giant salamanders often live in deep mountain streams with flowing water. The water quality is refreshing and pollution-free. The water quality of artificially cultured giant salamanders is easily contaminated, and a large number of pathogenic microorganisms often breed in polluted water bodies. When the giant salamanders are traumatized, these pathogenic microorganisms take advantage of the situation and cause disease.

(2) Impact of environmental conditions

Due to the artificial construction of salamander farms, it is difficult to meet the wild natural environmental conditions, especially the walls (bottoms) of the newly built salamander farms are relatively rough. , it is easy to scratch the skin of the giant salamander. When the giant salamander crawls and moves, its tail is constantly swinging, making it more susceptible to damage.

(3) The impact of large differences in stocking sizes

Generally speaking, the density of artificially stocked giant salamanders is relatively high. If the size of giant salamanders are very different and there is a lack of food, competition for food often occurs. In fighting, small individuals have weak ability to compete for food, and are often attacked and bitten by larger individuals, and their tails are often the target of attacks.

(4) Effects of malnutrition in feed

Giant salamanders are carnivorous amphibians and often feed on animal feed. When the feed fed has poor palatability and lacks necessary Nutrients, especially animal protein and certain trace elements, such as zinc, iron, calcium, microorganisms, etc., can induce giant salamanders to kill each other.

2. Symptoms of giant salamander tail rot disease

In the early stage of giant salamander suffering from this disease, small red dots or red spots often appear from the base of the tail stalk to the end of the tail, and the surrounding tissue is congested and inflamed, and the epidermis is slightly red. It is gray-white in color. When the disease period is too long, sore-like lesions are formed, and a large number of pathogenic bacteria and debris are often adhered to the lesions. In severe cases, muscle necrosis occurs at the lesion site, and the tail bones are exposed. The sick salamander loses appetite or stops eating, and its activity ability is significantly weakened. The tail swings weakly, and it will die soon.

3. Prevention methods

(1) Create comfortable environmental conditions

When building a salamander farm, lighting, drainage and irrigation pipes, bait tables, Habitat land and other facilities. Since giant salamanders like to live alone and are afraid of light, multiple artificial tunnels can be built with bricks in the pond. The diameter of the cave entrance is 12 to 20 cm. The cave is relatively spacious and the cave walls should be made as smooth as possible. Salamander species cannot be stocked immediately after the construction of the pond. , because the new cement pool is highly alkaline, and the suitable pH value for giant salamanders is 6 to 7.

The newly built cement pool can be filled with water, soaked continuously for 2 to 3 days, then drained, and repeated several times to make the pH value of the pool water close to neutral and the pool and cave walls to be sticky. When there is a smooth layer of attachments, put in the salamander seeds.

(2) Disinfection treatment

Before stocking salamander species, gentian violet solution with a concentration of 1% should be used for disinfection treatment. The method is that the ratio of medicine to water is 1:100. , soak the salamander seeds for 20 minutes. The gentian violet liquid has little irritation to the giant salamander's skin and can effectively prevent fungal and bacterial surface infections.

(3) Control water quality and water temperature

The water quality of the salamander pond should be kept fresh and pollution-free, and stream water or clear spring water should be used as much as possible. The pool water should be changed regularly. When conditions permit, the salamander pond can maintain flowing water all year round. The suitable water temperature for the growth of giant salamanders is 14°C to 28°C. In hot summer, it is more important to change the pool water.

(4) The individual sizes of the stockings are neat and tidy

The salamander species at this stage are all artificially bred, and the individual sizes are basically the same. However, after a period of breeding, the differences in individual sizes become increasingly large. The more obvious it is. At this time, screening should be carried out and the animals should be raised in separate pools to avoid the phenomenon of the big bullying the small and the strong bullying the weak.

(5) Feed high-quality feed

Giant salamander feed should be rich in nutrients such as protein and trace elements, such as fresh fish and shrimp, animal offal, animal blood, scraps, etc. It is a good bait for giant salamanders. When feeding food, adhere to the scientific feeding method of "timing, positioning, quality and quantity". Do not put animal offal, blood clots, scraps, etc. directly into the water. Otherwise, it will easily cause pollution to the water body. It is necessary to prevent waste of bait. It is also necessary to prevent some individuals from not being able to eat or not eating well.

4. Treatment methods

(1) When giant salamanders are found to be suffering from tail rot disease, the sick salamanders should be kept in isolation in time. If they are not kept separately, there will be endless troubles and possible disasters. The entire salamander farm. First, the pathogens continue to spread in the pool water and infect other individuals; second, healthy individuals can suck the blood from the affected area of ​​the sick salamander at any time, making the disease worse and transmitting the pathogen to healthy individuals.

(2) Use strong chlorine at a concentration of 0.3 to 0.4 ppm or chlorine dioxide at a concentration of 0.2 to 0.3 ppm to sprinkle the entire pond (including habitats, bait tables, etc.) once a day, and use continuously A course of treatment lasts for 3 to 4 days.

(3) For giant salamanders with serious illness, first soak the sick salamanders with 15-25ppm potassium permanganate or 0.3-0.5ppm malachite green solution for 15-20 minutes, and thoroughly Clean the attachments on the surface of the wound, and then apply anti-inflammatory drugs such as Xiaozhilong ointment or sulfur ointment to the affected area once a day, and it can be cured in 4 to 7 days.

(4) Use 2 to 3g of chloramphenicol and 2g of ten kannada raw powder + Vc2g + Ve2g + Vb2g (dosage per kilogram of body weight), mix the above drugs evenly into the bait and feed them, and use them for 3 consecutive days ~4 days.

[Edit this paragraph] Snack of the same name

A snack in Heze, Shandong.

Use jelly to make small droplets, which are also similar to small fish, so they are called giant fish.

When cooking, cook the salamander, put soy sauce, vinegar, cumin and other seasonings into the bowl, and put the cooked salamander into the bowl.

A bowl of small, white, elastic giant salamander that keeps swimming at the slightest movement. Eat it with a spoon. You can add seasonings according to your own taste.