Taxonomic notes: Section empty

This snake is widespread in the coastal lowlands of Asia and Australasia. It is known from peninsular India (northwest coast including Gujarat), Bangladesh, Sri Lanka (Anslem de Silva pers. comm. 2009), Myanmar, the Nicobar and Andaman Islands (Chandi 2006, de Rooj 1917, Smith 1941), Thailand (Taylor 1965), Cambodia (Saint Girons 1972), Vietnam (Nguyen et al. 2009, Campden-Main 1970), China (Hainan Island), the Philippines, Malaysia, Singapore, New Guinea and many of its satellite islands, Timor, the Solomon Islands (Ehmann 1992), northern Australia (along the coasts of Queensland, the Northern Territory and Western Australia) (K. Sanders pers. comm. 2008), and the Indonesian islands of Ambon, Flores, Java, Jobi, Schouten, Sulawesi, Sumatra, Ternate and We. In the Philippines this is a widespread species. It is known from Palawan, the Calamianes Islands, Panay and Masbate, and it seems likely that it occurs on all of the main, and many of the smaller, islands (Alcala 1986). In Vietnam recent records only exist from parts of the country's south (Q.T. Nguyen pers. comm. August 2011). It may be more widespread in this country, but surveys in the far south of Vietnam are lacking (Q.T. Nguyen pers. comm. August 2011).

This aquatic species is found in coastal tidal rivers, estuaries, and in the open sea (especially shallow seas over mud bottom), and coral reefs. In estuarine systems it is often found in the intertidal zone, including river mouths and mangroves and Nipa palm swamps (Cox et al. 1998, Steubing and Inger 1999, Cogger 2000). It feeds on fish and seldom leaves the water, typically being found at depths from 0-10 meters (Guinea 2007). In the Straits of Malacca, the file snake shares the marine habitat and fish resources with true sea snakes, and can be found up to 20 m deep (Voris and Glodek 1980). Animals have been recorded inland in the Philippines (A. Diesmos pers. comm.), Singapore (Ng 2011), and Cambodia, where they are associated with freshwater habitats, including Tonle Sap Great Lake in Cambodia (Saint Girons 1972). This snake appears to be tolerant of some degree of habitat disturbance (A. Diesmos pers. comm.). This viviparous snake exhibits seasonal reproduction, with ovulation around July and parturition five or six months later (Shine et al. 1995). Litters contain 5-12 young (Cox et al. 1998, Cogger 2000).

This species is common throughout its range, extremely common in some places (A. de Silva pers. comm. 2010). It is frequently observed in the nearshore areas of the Indian sub-continent and its backwaters (A. Lobo pers. comm. 2009). It was found to be relatively common in trawler bycatch in western Malaysia in 1989 (Stuebing and Voris 1990). The global population status is unknown but most likely to be stable. It is apparently uncommon in inland Cambodia (T. Neang pers. comm. August 2011). It is a common species in the Solomon Islands (M. McCoy pers. comm. November 2011).

The species was historically used for leather in the 1970s and 1980s. It has also been collected for the pet trade. The species is used in snake wine in Vietnam (Somaweera and Somaweera 2010) in very small numbers, with this study reporting just five individuals in trade. There is some local use for food in Indochina, but this is on a small scale (Q.T. Truong pers. comm. August 2011), and it is not among the more heavily-harvested species around Tonle Sap (T. Neang pers. comm. August 2011).Yuwono (1998) recorded the trade of this species from Java, and that it was always available in adequate numbers. There is no known trade in New Guinea.

The species is caught incidentally in gill nets that target homalopsid water snakes in Tonle Sap Lake, Cambodia (Brooks et al. 2007). This species is caught incidentally by trawlers (Stuebing and Voris 1989) and a directed harvest also occurs for the pet trade. Due to the species' preference for shallow areas, (generally below 15 m) it is caught as bycatch in shallow water fishing operations including shore seines and gill nets, in addition to trawling, and this is thought to be the main threat to the species in India.  A recent study by de Silva et al. (2010) found as many as 15 snakes dead in one fishing net, with approximately 200 boats operating in the area. 

High levels of pollution in India may also be a threat, however, it still appears to survive in the highly polluted backwaters of Mumbai (A. Lobo pers. comm. 2009). In Indonesia, this species is not known to have been harvested on a commercial scale since the 1980s (G. Saputra pers. comm. 2009).  In the Philippines, it is collected for the national and international pet trade (J. Gatus pers. comm. 2009). There is collection and trade of this species in the Philippines for its use in the leather industry (regulated by the Bureau of Fisheries and Aquatic Resource).

The other two species of acrochordids appear to be capable of withstanding considerable harvesting pressures, probably higher than those currently in operation (Shine et al. 1995), and so it is likely that this smaller, more marine species is also likely to sustain high harvesting levels.

In Vietnam, coastal development, farming and the establishment of shrimp and fish farms are destroying and degrading mangrove forest. There is not enough data to indicate whether this represents a major threat to the local population of this species in Vietnam (Q.T. Neang pers. comm. 2011).

There is no known use or threats to this small snake in New Guinea.

• 5.4.4 Unintentional effects: (large scale) [harvest]
• 5.4.3 Unintentional effects: (subsistence/small scale) [harvest]
• 1.3 Tourism & recreation areas
• 5.4.1 Intentional use: (subsistence/small scale) [harvest]
• 9.1.3 Type Unknown/Unrecorded
• 2.1.2 Small-holder farming
• 2.4.2 Industrial aquaculture

There are no conservation measures in place for this species. In view of the species' extensive geographic range, it seems likely that populations are present in a number of protected areas, and it is presumed to occur within local Marine Protected Areas throughout its range. It is not known to be present in any protected areas in Vietnam. No direct conservation measures are currently needed for this species as a whole. While it is subject to some commercial collection, the species is not currently listed by CITES. Further details are needed into the impact of collection of animals for use in the leather and pet trade, and on the effects of habitat degradation.

Acrochordus granulatus has been assessed as Least Concern. It has a wide distribution throughout Indo-Malaysia and Australasia. It is abundant in suitable habitat, is not affected by any significant threats and is presumed to occur in a large number of protected areas.

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