The smallest of the world's otters, about 0.9m long, weighing around
5kg. This otter lives in extended family groups around a breeding alpha
pair. Group sizes of more than 20 animals have been recorded. These
otters are extremely manually dextrous, using their forepaws to feel for
molluscs and crustaceans in rocks, vegetation and mud. They are the
least aquatic of all the otters.
This species used to be known as Amblonyx cinereus, and before
that as Aonyx cinerea. DNA work by Koepfli & Wayne (1998 & 2003)
indicated that the Asian Small-Clawed Otter is a sister species to the
African Clawless and Congo Clawless Otters. Aonyx is the older
name, so the Asian Small-Clawed Otter is now Aonyx cinereus.
CITES Identification Sheet
Small-Clawed Otters prefer shallow water, with a good food supply, and
moderate to low bankside vegetation. They demonstrate a high climatic
and trophic adaptability, occurring from tropical coastal wetlands up to
mountain streams. They make use of freshwater and peat swamp forests,
rice fields, lakes, streams, reservoirs, canals, drainage ditches, rice
paddies, mangroves, tidal pools, and along the coastline. In mountainous
areas, they frequent swift-flowing forest streams with rocks and
boulders. Their preferred food is crustaceans and molluscs. Across much
of their range they are sympatric with Eurasian Otters (Lutra lutra),
Smooth-Coated Otters (Lutrogale perspicillata) and Hairy-Nosed
Otters (Lutra sumatrana), and there is clear evidence of niche
separation between the species.
Although the species' range appears large, in the last decade, actual
distribution has shrunk, especially in the west, compared to historical
records. They are currently found from the Himalayan foothills of
Himachal Pradesh eastward throughout south Asia, extending up to
Philippines and down through Indonesia. A population which was
previously thought to be isolated, exists in the hill ranges of the
Western Ghats, and more recently they have been reported from protected
areas in the Eastern Ghats which might better explain their distribution
in South India. Their range in the Western Ghats too has increased with
sightings and evidence being reported from the northern Western Ghats,
well extending their range beyond the hills of Coorg and Ashambu. They
were formerly found in Sri Lanka, but their current status there is
unknown. The only areas in which these animals are today known to be
common are Peninsular Malaysia, especially in Kedah, in the western
forests and southern marshes of Thailand, and in the Western Ghats of
India where it appears to be the most common species of otter.
Red List Category VU (Vulnerable), population decreasing
Year Assessed 2015
Assessor Hussain, S.A. & de Silva, P.K.
Evaluators Conroy, J. (Otter Red List Authority) & Schipper, J. (Global
Mammal Assessment Team)
The main threat throughout Asian is habitat destruction because of
deforestation (loss of the smaller hill streams), agriculture
(especially tea and coffee plantations in India, draining of peat swamp
forests, and destruction of coastal mangroves for aquaculture) and
settlement. Water courses are being polluted with pesticides from
plantations and other intensive agriculture, and heavy metals, affecting
the gill-feeders on which this species depends, and interfering directly
with otter physiology. Prey biomass is also being reduced by
overexploitation, and in some places, the vast aquaculture industry
regards otters as pests and persecutes them directly. On a more positive
note, there is increased evidence of otters using modified landscapes
such as coffee and tea plantations in India and though habitat
destruction might be of concern, direct threats need to be better
understood. They have even been recorded from storm water drains in
Jakarta, indicating their adaptability to modified habitats. These
otters are known to be highly elusive in disturbed landscapes, and this
could potentially contribute to the perception of a decline in
Although international and national level legal protection is in place,
local legislation is needed. The impact of protection measures on
livelihoods needs to be assessed and answered. Habitat protection and
inter-population corridors need to be established. Research on all aspects
of this species biology and ecology is needed.
Source: Padma K de Silva,
IUCN/SSC Asian coordinator
||Studies on the range and habitat utilization of small-clawed otter in South India.
||Studies on diet, interactions with humans and threats including the pet trade in Indonesia
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TRAFFIC, 9th December 2009: Otters feel the heat in Southeast Asia