Chinese sturgeon

Chinese sturgeon
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Acipenseriformes
Family: Acipenseridae
Genus: Acipenser
Species: A. sinensis
Binomial name
Acipenser sinensis
Gray 1835
Synonyms[2][3]
  • Acipenser kikuchii Jordan & Snyder 1901

The Chinese sturgeon (Acipenser sinensis; Chinese: 中華鱘; pinyin: zhōnghuá xún) is a critically endangered member of the family Acipenseridae in the order Acipenseriformes. Historically, this anadromous fish was found in China, Japan, and the Korean Peninsula, but it has been extirpated from most regions due to habitat loss and overfishing.[1]

It is strictly protected by the Chinese government, named a "national treasure" much like its mammalian counterpart, the giant panda. China has several conservation programmes, including reserves specifically aimed at this species and restocking through release of juveniles in the Yangtze River.[1]

Physical appearance

Sturgeon are comparatively basal species of fish, whose earliest fossils date back to the Cretaceous period.[4] They are best-known members of the bony fish taxon Chondrostei, a group of bony fishes that have cartilaginous skeletons superficially similar to the skeletons seen in the unrelated chondrichthyan fishes. In Qing Dynasty Chinese cuisine, its meat and cartilaginous skeleton was often cooked and served together, and considered a delicacy.[5]

Adult Chinese sturgeon can range between 2 and 5 m (6.6 and 16.4 ft) in total length, and weigh between 200 to 500 kg (440 to 1,100 lb), ranking them among the largest sturgeon in the world.[6] Its head is acuminate, with the mouth under its jaw.[7]

Lifecycle

Chinese Sturgeon in Dalian Laohutan Ocean Park

Most sturgeon spawn in fresh water and migrate to salt water to mature. The Chinese sturgeon can be considered a large freshwater fish, although it spends part of its lifecycle in seawater, like the salmon,[8] except Chinese sturgeon spawn multiple times throughout their lives.

The Chinese sturgeon has a habit of upstream migration; it dwells along the coasts of China's eastern areas and migrates back up rivers for propagation upon reaching sexual maturity. It has the longest migration of any sturgeon in the world, and once migrated more than 3,200 km (2,000 mi) up the Yangtze.[9] The sturgeon's reproductive capacity is poor; it may breed three or four times during its life, and a female sturgeon can carry in excess of a million eggs in one cycle, which are released for external fertilisation when mature. The survival rate to hatching is estimated to be less than 1%.[8]

Habitat

The Chinese sturgeon is a critically endangered species native to China. It is largely dispersed over the main streams of the Yangtze River and coastal regions of Qiantang River, Minjiang River, and Pearl River.[7] The adults are predators that consume any aquatic animal that can be swallowed, while the young feed on aquatic insects, larvae, diatoms, and humic substances.[7]

In the 1970s, an estimated 2,000 Chinese sturgeon spawned in the Yangtze River every year. Now, that number is down to several hundred due to the threats to its habitat, such as pollution[10] and other human action. The channel for adult fish migrating to traditional spawning sites such as the Jinsha River in the upstream of Yangtze River was blocked after the construction of the Gezhouba Dam hydroelectric power project in the early 1980s.[9]

The sturgeon is also highly sensitive to increased noise on the river caused by growing river traffic, as well as being vulnerable to death or injury by boat propellers.[9]

Protection and research

Chinese sturgeon at the Beijing Aquarium

The primitiveness of the Chinese sturgeon makes it a great academic interest in taxonomy and biology. For this reason, China has been studying ways to breed and preserve the endangered species, classified as "China's Class One Protected Animals" since the 1970s.[4]

Built in 1982, the Chinese Sturgeon Museum is part of the Chinese Sturgeon Institution of China which is using artificial breeding techniques to try to preserve this endangered species. The museum is located on a small island called Xiaoxita in the Huangbo River, within Yiling District of Yichang.[11]

Repopulation program

The Yangtze River Fisheries Research Institute of the Chinese Academy of Fisheries Sciences in Jingzhou is one agency charged with breeding sturgeon in captivity for restoring the river population before the species disappears.[9]

Some success has been claimed by the authorities from artificial inducement for spawning and stream discharge for incubation.[7] On 29 April 2005, to mark the 20th anniversary of the China's efforts to protect the species, over 10,000 sturgeon fry, 200 junior sturgeon, and two adult fish were released into the Yangtze River at Yichang. During the course of the project, 5 million fish bred in captivity have been released into the wild.[10] However, in 2007, 14 young sturgeon were surveyed near the mouth of Yangtze compared with 600 the year before, causing concern that effort was a losing battle in the crowded and polluted Yangtze river.[12]

To mark China's hosting the Olympic Games, the Chinese Central Government made a gift of five sturgeon, symbolising the five Olympic rings to Hong Kong. The fish made their debut in Ocean Park Hong Kong on 20 June 2008.[4] One of the fish, however, died by January 2009 due to unknown causes.

See also

References

  1. 1 2 3 Qiwei, W. (2010). "Acipenser sinensis". The IUCN Red List of Threatened Species. IUCN. 2010: e.T236A13044272. doi:10.2305/IUCN.UK.2010-1.RLTS.T236A13044272.en. Retrieved 6 January 2018.
  2. ↑ Froese, R.; Pauly, D. (2017). "Acipenseridae". FishBase version (02/2017). Retrieved 18 May 2017.
  3. ↑ "Acipenseridae" (PDF). Deeplyfish- fishes of the world. Retrieved 18 May 2017.
  4. 1 2 3 ""Living fossil of fish" Chinese sturgeons debut in HK". Xinhua. 20 June 2008.
  5. ↑ "River Delicacies 3: Sturgeon (鱘魚)". Suiyuan shidan. 2014-12-18. Retrieved 2016-02-10.
  6. ↑ Dwayne Meadows; Heather Coll (October 2013). "Status Review Report of Five Foreign Sturgeon" (PDF). Report to Office of Protected Resources. National Marine Fisheries Service. p. 78. Retrieved November 29, 2014.
  7. 1 2 3 4 "Chinese sturgeon". Chinese Ministry of Culture. Archived from the original on 29 September 2012. Retrieved 15 July 2008.
  8. 1 2 Elaine WU (15 July 2008). "At home in saltwater and fresh". South China Morning Post. Hong Kong.
  9. 1 2 3 4 Stefan Lovgren (15 August 2007). ""Living Fossil" Fish Making Last Stand in China". National Geographic. Retrieved 15 July 2008.
  10. 1 2 "Chinese Sturgeon Set Free". China.org.cn. 29 April 2005. Retrieved 15 July 2008.
  11. ↑ Chinese Sturgeon Museum
  12. ↑ "Scientists sound alarm as Chinese sturgeon battle for survival". AFP. 23 July 2007. Archived from the original on 18 November 2007. Retrieved 15 July 2008.
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