Hucho bleekeri
| Hucho bleekeri | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Salmoniformes |
| Family: | Salmonidae |
| Genus: | Hucho |
| Species: | H. bleekeri |
| Binomial name | |
| Hucho bleekeri Kimura, 1934 | |
Hucho bleekeri, or the Sichuan taimen, is a species of freshwater fish in the salmon family (Salmonidae), endemic to China. Its typical habitat is mountain streams and small rivers and it is found in the catchment areas of the Dadu River in Sichuan and Qinghai Provinces, and the Hanjiang River. It is a grey fish with a silvery belly growing to a length of 72 cm (28 in). Populations of this fish are declining, it principally being threatened by habitat loss and illegal fishing, and the International Union for Conservation of Nature has rated its conservation status as "critically endangered".
Description
Individuals are usually dark gray on the back with a silvery white underside and small cross-shaped spots scattered on the body and gill cover. Adults grow up to 720 mm in length.[1]
Distribution and habitats
Sichuan taimen are endemic to central China, where they are found in the upper tributaries of the Yangtze River in Sichuan Province, the upper and middle reaches of the Dadu River in Sichuan and Qinghai Provinces, and the upper reaches of the Hanjiang River south of the Qin Mountains in Shaanxi Province.[1] It dwells predominantly in fast-flowing streams with sandy and gravel substrates.[2] The species prefers mountain brooks at 700–3,300 meters above sea level with high dissolved oxygen (>5 mg/l) and a low water temperature (<15°C).[3]
Diet
Juveniles feed mostly on zooplankton and insects, while adults are largely piscivorous.[2]
Threats
According to the IUCN, the Sichuan taimen is threatened mostly by habitat loss from the construction of hydropower stations, erosion of soil due to deforestation, road construction, and sand excavation. Despite legal protections, the species is also threatened by illegal fishing. Recent studies have estimated the species has endured a 50-80% decline in population over the past three generations, and the decline is expected to continue. Only an estimated 2,000-2,500 mature individuals survive.[1]
See also
References
- 1 2 3 Song, Z. 2012. Hucho bleekeri. In: IUCN Red List of Threatened Species. Version 2012.2. <www.iucnredlist.org>. Downloaded on 26 October 2012.
- 1 2 Froese, Rainer and Pauly, Daniel, eds. (2014). "Hucho bleekeri" in FishBase. April 2014 version.
- ↑ Hu et al. 2008. "Threatened fishes of the world: Hucho bleekeri Kimura, 1934 (Salmonidae)." Environmental Biology of Fishes 82.4: 385-386.
- Kimura, S. (1934) Description of the fishes collected from the Yangtze-kiang, China, by late Dr. K. Kishinouye and his party in 1927-1929 The Journal of the Shanghai Science Institute, Section III. Vol. I, 11-247. (original description)