Animal Spotlight: Chinese Giant Salamander

Taxonomy:KONICA MINOLTA DIGITAL CAMERA

  • Kingdom: Animalia
  • Phylum: Chordata
  • Class: Amphibia
  • Order: Caudata
  • Family: Cryptobranchidae
  • Genus: Andrias
  • Species: Davidianus
  • Average Length: 3.77 ft (1.15 m)
  • Longest Recorded: 5.9 ft (1.8 m)
  • Average Weight: 55-66 lbs (25-30 kg)
  • Heaviest Recorded: 130 kg (59 kg)

The Chinese giant salamander is the largest living amphibian out of the 6,000 amphibian species worldwide. It is also one of the three giant salamander species in the family Cryptobranchidae, joining the Japanese giant salamander and the American hellbender.

Mainly found in central, southwestern, and southern China, the Chinese giant salamander spends its whole life as an aquatic species in mountain streams and lakes with clear-fast-running water around forested areas. Typically, they live at moderate altitudes, below 1500 meters above sea level, especially between 300 to 800 meters. The species ranges from Qinghai and Sichuan to Guangxi, Guangdong, and Jiangsu provinces along the mountain stream tributaries of the Pearl (Zhu Jiang), Yellow (Huang He), and Yangtze Rivers.

There are currently six “Giant Salamander Reserves” in China that use the Chinese giant salamander as their main conservation target. These are located in Lushi, Qingyaoshan, Youyang, Taibai, Yongshun, and Zhangjiajie Giant Salamander Nature Reserve. Unfortunately, all six are affected by a combination of negative factors such as shortage of funding and personnel, lacking a conservation action plan, poaching, uncertain reserve status, and lack of protection for salamander habitat.

In 1999, a 100,000 hectare area of Mount Wuyi, China, a World Heritage Site, was dedicated to conserving its biodiverse region, including the habitat of the Chinese giant salamander. However, the surrounding area has a growing population; the development around the reserve and increased tourist activity within the reserve may cause negative effects on its natural environment.

The Taiwanese population has probably been introduced from animals escaping from salamander farms. Despite being widespread, the Chinese giant salamander’s range has been severely fragmented.

Physical Characteristics:

 
Credit: Daniel Heuclin/NPL

The Chinese giant salamander is heavily built, with a flat, broad head and a short snout. Its small round eyes are positioned far back on the sides of its head, providing poor vision. They lack eyelids and are unable to focus on the same object at once. Therefore, the salamander relies heavily on smell and touch

It has a wide mouth, a large tongue, and small but numerous teeth. The species also possesses vomerine teeth, two small bumps found on the roof of the mouth specifically used to grip onto prey, and a long arc of maxillary, or jaw, teeth. The fusion point of the upper and lower jaw is flexible, with large bundles of elastic cartilage. This allows the salamander to open its mouth to reach 40°.

To feed,  this species opens its mouth by causing the lower jaw to depress, or drop, quickly, sucking in nearby prey items. This feeding method is also known as asymmetrical buccal suction.

The body, like the head, also appears just as a flattened, with a broad, compressed tail that comprises almost 60% of the body length. It has a series of costal grooves along the sides of the body where the ribs are located as well as a vertebral groove along the back.

 
Credit: Daniel Heuclin/NPL

Like other amphibians, this species also has smooth skin that lacks scales. Skinfolds, areas of skin where it folds, are present along the sides of the body from the back of the head to the tail tip. Individuals are usually dark brown, black, or greenish in color with blotched, marbled and/or spotted patterns.

Chinese giant salamander larvae resemble the adults in shape, only 30 mm in length after it hatched. In larvae form, the salamander does have external gills to breathe. However, once it reaches 200 to 250 mm in length, the gills start to reduce and lose its effectiveness, though they are never fully lost once in adult form. Instead, the salamander’s moist skin acts as a respiratory surface. Oxygen would be absorbed from the water and carbon dioxide will be released through the skin. Adult salamanders develop skinfolds to increase the surface area for oxygen intake.

Due to its large size and absorbing oxygen from the water through its skin, the Chinese giant salamander is confined to flowing water.

Diet:

During the day, the species will usually be located in dark hiding places, venturing out only to stalk their prey and feed. The Chinese giant salamander is a top endemic predator of its ecosystem where it predominantly feeds on fish and crustaceans. However, it will also feed on insects and their larvae, frogs and their tadpoles, worms, molluscs, aquatic reptiles, and small mammals. The salamander may also exhibit cannibalistic behavior and is known to eat carrion and their own shed skin and eggs.

Behavior:

The Chinese giant salamander is thought to be generally nocturnal, although they become more diurnal during the breeding season which occurs from July to September.

Mating behavior described for Japanese giant salamanders is probably similar for the Chinese giant salamander.

Up to several females will lay approximately 500 unfertilized eggs in the same underwater burrow or “breeding cavity” that is occupied by a male. This male, who will also fertilize the eggs, will aggressively guard the eggs against any intruders.  He will care for the nest until the eggs hatch after 50 to 60 days (1 to 2 months).

Conservation/Threats:

Listed as Critically Endangered in the IUCN Red List of Threatened Species due to an observed drastic population decline, the Chinese giant salamander was once reasonably common. Over the last three generations, its numbers have declined by an estimate of 80% with only few known surviving populations. These individual populations have become smaller and more fragmented. No accurate population estimate is currently available.

Chinese Food: Giant salamander
Credit: BBBar/Alamy

Scientists and conservationists were able to observe the decline in numbers through the catch rates of Chinese giant salamanders. Since the 1960s, commercial overexploitation has been the main threat to this species because its meat is considered to be a delicacy in China. In the 1970s, around 2,500 to 3,000 kg were harvested each year with the number declining as they became rarer and harder to find. Even today, they remain a lucrative option for poachers, who can sell its flesh for around $100 US dollars per kg or around $43 US dollars per lbs.

And although there is commercial farming, the vast majority of these salamanders that are being traded are believed to have originated from the wild. The hunters have had no success in breeding a second generation from the captured Chinese giant salamanders, making the captive population unsustainable and requiring the capture of more animals from the wild.

Infectious diseases spread quickly on these farms as well as the lack of regulations and evaluations in the breeding and use of hormones might be damaging the wild populations.

Closing down the farms is not a viable option because the local governments up to the central government have invested so much money into the business. Instead, researchers say the farms need to be better managed so that no captive salamanders are released into the wild. In the past, the Chinese government has encouraged the release of captive salamanders to boost wild populations. But, they weren’t screened for disease nor were there any tests to see if their genetic makeup was suitable for the environments they were being rehomed. Without any monitoring, it was impossible to evaluate if the scheme was a success or a failure.

img_94961-255311This species also suffers from habitat destruction and degradation. The construction of dams converts their free-flowing streams and rivers into standing water or dry up. Deforestation around the streams exacerbates soil erosion and increases the runoff and siltation of the streams, reducing water quality and oxygen levels. Factors such as water pollution from mining activity and farming also occurs throughout its range.

The Chinese giant salamander is listed on Appendix I of CITES, which includes species threatened with extinction. This makes trade in individuals of these species is permitted only in exceptional circumstances. Unfortunately, although CITES regulates international trade in the species, it has no jurisdiction over the domestic trade within China, the primary market. However, China listed the amphibian as a Class II State Major Protected Wildlife Species.

Interesting Facts:

  • Because its call resembles a baby’s cry, the Chinese Giant Salamander is also nicknamed as ‘Wa Was Yu’, meaning baby fish
  • Another local name in Shaanxi Province is “Zuh Bu Chi’, meaning pig not eat. In the 1960s and 1970s, during the period of starvation in China, not even the pigs wanted to eat the giant salamander.
  • The Yin and Yang symbol of opposites in Asian culture is thought to have originally been two Chinese giant salamanders, harmoniously intertwined.
  • The Chinese giant salamander has its place in mythology. In one Asian myth, the salamander makes its home in fires. Early travellers to China were shown garments that was, or was told, to have been woven from the “wool” of the salamander, making it fire-proof. The garments were actually woven from asbestos.

chinese-giant-salamander-banner2
References + For More Reading

Chinese Giant Salamanders Organization Website

EDGE: Chinese Giant Salamander (Andrias davidianus)

AmphibiaWeb: Andrias davidianus

Amazing Chinese Giant Salamanders Are Bigger Than You

Zoological Society of London: Chinese giant salamander conservation

Arkive: Chinese giant salamander

EOL: Andrias davidianus (Chinese Giant Salamander)

IUCN: Andrias davidianus

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