Asian small-clawed otter
Asian small-clawed otter | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Carnivora |
Family: | Mustelidae |
Subfamily: | Lutrinae |
Genus: | Aonyx |
Species: | A. cinereus
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Binomial name | |
Aonyx cinereus (Illiger, 1815)
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Asian small-clawed otter native range (in green) | |
Synonyms | |
Amblonyx cinereus |
The Asian small-clawed otter (Aonyx cinereus), also known as the oriental small-clawed otter and the small-clawed otter, is an
The Asian small-clawed otter lives in riverine habitats,
It is listed as
.Taxonomy
Lutra cinerea was the
- Lutra concolor proposed by Constantine Samuel Rafinesque in 1832 was a uniform coloured otter from Assam. Rafinesque also proposed Amblonyx as name for a subgenus for otters with short, obtuse claws.[3]
- Lutra leptonyx proposed by Thomas Horsfield in 1824 were two adult small-clawed otters collected in Java.[4] It was subordinated to the genus Aonyx by John Edward Gray in 1843.[5]
- Amblonyx cinerea nirnai proposed by Reginald Innes Pocock in 1940 was a dark brown small-clawed otter from Virajpet in South India.[6]
Phylogeny
Results of a mitochondrial
The Asian small-clawed otter groups with the
Characteristics
The Asian small-clawed otter has deep brown fur with some rufous tinge on the back, but paler below. Its underfur is lighter near the base. The sides of the neck and head are brown, but its cheeks, upperlip, chin, throat and sides of the neck are whitish.[10] Its skull is short, and the naked
The Asian small-clawed otter is the smallest otter species in Asia. In head-to-body length, it ranges from 470 to 610 mm (18.4 to 24 in) with a 260 to 350 mm (10.2 to 13.6 in) long tail. The tapering tail is thick and muscular, especially at the base, and more than half the length of the body. Hind feet are 97 to 102 mm (3.8 to 4 in) long. Length of skull ranges from 3.3 to 3.7 in (84 to 94 mm). It does not have upper premolars and only four cheek teeth above.[13] Adult captive otters range in weight from 2.7 to 3.5 kg (6.0 to 7.7 lb).[14]
Distribution and habitat
The Asian small-clawed otter's native range comprises parts of India to Southeast Asia including the islands of
In the 1980s, a few Asian small-clawed otters escaped from captivity in England and established a population in the wild.[16][17]
Behaviour and ecology
The Asian small-clawed otter is mostly active after dark.[18][19] It lives in groups of up to 15 individuals.[19] In the Bangladesh Sundarbans, 53 individuals were recorded in 351 km (218 mi) of water courses in 13 locations between November 2014 and March 2015. Group size ranged from one to 12 individuals.[20] Group members communicate using 12 or more distinct calls, and utter a variety of yelps and whimpers.[12] When disturbed, they scream to rally the help of others.[21]
When swimming on the surface, otters row with the forelimbs and paddle with the hind limbs.[22] When diving under water, they undulate their bodies and tails. Captive otters swim at speeds of 0.7–1.2 m/s (2.3–3.9 ft/s).[14]
Observations of wild Asian small-clawed otters revealed that they smear their
Diet
The Asian small-clawed otter feeds mainly on crabs, mudskippers and Trichogaster fish. Its diet varies seasonally. When and where available, it also catches snakes, frogs, insects, rats and ricefield fish like catfish, Anabas testudineus and Channa striata.[19] The size of crabs found in spraints in Huai Kha Khaeng Wildlife Sanctuary ranged in carapace width from 10 to 44 cm (3.9 to 17.3 in).[23] Captive Asian small-clawed otters were observed to leave shellfish in the sun so the heat causes them to open, making it possible for them to eat them without having to crush the shells.[12]
Reproduction
Information about the Asian small-clawed otter's
Threats
The Asian small-clawed otter is threatened by poaching for its fur, loss and destruction of habitats such as hill streams, peat swamp forests and mangroves for aquaculture projects. Threats in India include deforestation, conversion of natural habitat for tea and coffee plantations, overfishing of rivers and water pollution through pesticides.[1]
It is the most sought after otter species for the illegal
Conservation
The Asian small-clawed otter was listed on
In captivity
The Association of Zoos and Aquariums established a Species Survival Plan for the Asian small-clawed otter in 1983 to encourage research on captive breeding.[30][31]
In Europe, Zoo Basel keeps Asian small-clawed otters together with Indian rhinoceros.[32]
Asian small-clawed otters with osteoporosis display resorption of hyperactive bone and cartilage by osteoclasts in many bone sites, which causes pockmarks on all the bones.[33]
References
- ^ . Retrieved 10 December 2022.
- ^ Illiger, C. (1815). "Überblick der Säugethiere nach ihrer Verteilung über die Welttheile". Abhandlungen der Königlichen Preußischen Akademie der Wissenschaften zu Berlin. 1804−1811: 39−159. Archived from the original on 4 April 2019. Retrieved 12 June 2020.
- ISBN 9780665414664.
- ^ Horsfield, T. (1824). "Lutra leptonyx". Zoological researches in Java, and the neighbouring islands. London: Kingsbury, Parbury & Allen. pp. 185–191.
- ^ Gray, J. E. (1843). "The Wargul. Aonyx leptonyx". List of the specimens of Mammalia in the collection of the British Museum. p. 71.
- ^ Pocock, R. I. (1940). "Notes on Some British Indian Otters, with Description of two new Subspecies". The Journal of the Bombay Natural History Society. 41 (3–4): 514–517.
- .
- S2CID 24619297.
- PMID 28128366.
- ^ Blanford, W. T. (1888). "Lutra leptonyx. The clawless Otter". The Fauna of British India, Including Ceylon and Burma. Vol. Mammalia. London: Taylor and Francis. pp. 187–188.
- .
- ^ .
- ^ Pocock, R. I. (1941). "Genus Amblonyx, Rafinesque". The Fauna of British India including Ceylon and Burma. Vol. Mammalia II. London: Taylor and Francis. pp. 303–317.
- ^ S2CID 22682528.
- ^ Melisch, R.; Kusumawardhani, L.; Asmoro, P. B. & Lubis, I. R. (1996). The otters of west Java – a survey of their distribution and habitat use and a strategy towards a species conservation programme. Bogor, Indonesia: Wetlands International – Indonesia Programme.
- ^ Jefferies, D. J. (1989). "The Asian short-clawed otter Amblonyx cinerea (Illiger) living wild in Britain". Otters (Earsham). 2 (3): 21–25.
- ^ Jefferies, D. J. (1991). "Another record of an Asian short-clawed otter living free in Oxford with notes on its implications". Journal of the Otter Trust. 2 (2): 9–12.
- ^ Hutton, A. F. (1949). "Notes on the Snakes and the Mammals of the High Wavy Mountains, Madura District, South India. Part II – Mammals". Journal of the Bombay Natural History Society. 48 (4): 681–694.
- ^ a b c d Foster-Turley, P. (1992). Conservation ecology of sympatric Asian otters Aonyx cinerea and Lutra perspicillata (PhD Dissertation). Gainesville, Florida: University of Florida.
- ^ Aziz, M.A. (2018). "Notes on population status and feeding behaviour of Asian Small-clawed otter (Aonyx cinereus) in the Sundarbans mangrove forest of Bangladesh". IUCN Otter Specialist Group Bulletin. 35 (1): 3–10.
- S2CID 44011643.
- JSTOR 1382481.
- .
- ^ .
- ^ Sobel, G. (1996). Development and validation of noninvasive, fecal steroid monitoring procedures for the Asian small-clawed otter, Aonyx cinerea (Master of Science). Gainesville, Florida: University of Florida.
- ^ Maslanka, M. T. & Crissey, S. D. (1998). "Nutrition and diet". In Lombardi, D. & O’Connor, J. (eds.). Asian small-clawed otter (Aonyx cinerea) husbandary manual. Powell, Ohio: Columbus Zoological Gardens and AZA Asian Small-Clawed Otter SSP. pp. 1–18.
- ^ Gomez, L. & Bouhuys, J. (2018). Illegal Otter Trade in Southeast Asia (PDF). Kelana Jaya, Selangor, Malaysia: Traffic Southeast Asia Regional Office.
- ^ Gomez, L. & Shepherd, C. R. (2019). "Stronger International Regulations and Increased Enforcement Effort is needed to end the Illegal Trade in Otters in Asia" (PDF). IUCN Otter Specialist Group Bulletin. 36 (2): 71–76.
- ^ DTE Staff (2019). "CITES CoP 2019: Otters given highest protection from trade". DownToEarth.
- .
- ^ Foster-Turley, P. (1986). "A progress report on the species survival plan for Asian small-clawed otters in United States zoos". Otter Specialist Group Bulletin. 1: 19–21.
- ^ "Zoo-Nachwuchs sorgt für Trubel". Zoo Basel (in German). 2012.
- PMID 32009030.
External links
- "Asian Small-clawed Otter". IUCN Otter Specialist Group.
- "Aonyx cinerea, Oriental small-clawed otter". Animal Diversity Web.
- "Asian small-clawed otter". Smithsonian’s National Zoo & Conservation Biology Institute. 25 April 2016.
- "Ban on endangered otter trade to take effect amid pet boom in Japan". Kyodo News. 2019.