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Description |
Geographic Range [top]
Range Description: Hog Deer historically occurred from Pakistan, throughout northern and northeastern India, including the Himalayan foothill zone, east across non-Sundaic Southeast Asia and, marginally, southern China (southern Yunnan province), but it is now reduced to isolated subpopulations within this range. It is almost extirpated from east of Myanmar. It is extinct in Thailand (where it has, however, been reintroduced) and almost certainly in Viet Nam and Lao PDR (Humphrey and Bain 1990, Duckworth et al. 1999, Tordoff et al. 2005, R.J. Timmins pers. comm. 2008). Very small numbers have been found recently in Bangladesh and in five areas in Cambodia (Khan 2004, Maxwell et al. 2007, Timmings and Sechrest 2010, Brook et al. 2015). A report on the internet in 2007 from China turned out to refer to a young Sambar (B.P.L. Chan pers. comm. 2012). Hog Deer still probably occurs in at least several areas of Myanmar (J.W. Duckworth in litt. 2008, from various sources), and localised subpopulations survive in northern and northeastern India, Nepal, Bhutan (few recent data) and Pakistan (status uncertain; Biswas and Mathur 2000, Biswas 2004). Hog Deer has been introduced (not mapped) into Australia (specifically the coastal regions of south and east Gippsland; Moore and Mayze 1990), the United States (Texas, Florida and Hawaii; Grubb 2005) and it is presumed introduced into Sri Lanka; however there remains some discussion as to whether the species is native or introduced into Sri Lanka (Vishvanath et al. 2014) so the species is retained here as non-native until definitive information is received.
Countries occurrence:
Native:
Bangladesh; Bhutan; Cambodia; India; Nepal; Pakistan
Possibly extinct:
China; Lao Peoples Democratic Republic; Myanmar; Viet Nam
Reintroduced:
Thailand
Introduced:
Australia; Sri Lanka; United States
Additional data:
Range Map: Click here to open the map viewer and explore range.
Population [top]
Population: Pakistan
Hog Deer is confined to isolated riverine grasslands along the Indus valley and its upper tributaries, mostly in the Indus River forest reserves of Sind Province, with small subpopulations around the Indus mouth and to the north of Sukkur (Roberts 1977). The species was listed for the protected areas of Chashma Lake Wildlife Sanctuary, Head Islam/Chak Kotora Game Reserve (greatly reduced in number), Lal Suhanra National Park (reintroduced), Taunsa Barrage Wildlife Sanctuary, and possibly Rasool Barrage Wildlife Sanctuary (WCMC 1992), but no information more recent than Whale (1996) has been traced.
India
Hog Deer is found mainly in the Terai grasslands along the Himalayan foothills and the flood-plains of the Rivers Ganges and Brahmaputra, from Punjab in the west to Arunachal Pradesh in the east (Tandon 1989, Johnsingh et al. 2004, Biswas 2004). Johnsingh et al. (2004), who made extensive surveys of the Terai Arc Landscape of India (for Tiger, Panthera tigris, and various prey species), considered that Dudhwa Tiger Reserve is excellent habitat for Hog Deer; that there was a reasonable subpopulation in Pilhibit Forest Division, particularly the Lagga Bagga forest block (now within a Tiger reserve; B. Long pers. comm. 2008); that Kishanpur Wildife Sanctuary (203 km2), with one of the few remnants of Terai habitat in India, supported considerable numbers, and that Katarniaghat Wildife Division also held Hog Deer. Assessments conducted specifically for Hog Deer by Biswas et al. (2002; see also Biswas 2004) for India surmised that populations remained in 29–34 areas, with significant numbers only in the following: Arunachal Pradesh: 100–200 in D’ering, and 20–50 in Namdapha; Assam: 20–50 in Dibrusaikhowa, over 1,000 in Kaziranga (but see below), over 1,000 in Manas, 20–50 in Nameiri, 200–500 in Orang, 20–50 in Kobuchapori, 20–50 in Burachapori, and 20–50 in Sunai Rupa; Bihar: 100–200 in Valmiki; Uttrakand (= Uttaranchal): 200–500 in Corbett Tiger Reserve (but see below); Uttar Pradesh: 1,000–2,000 in Dudhwa, 20–50 in Katarniaghat, 100–200 in Kishanpur, and 20–50 in North Kheri Forest Division; and West Bengal: 100–200 in Gorumara and a population at Jaldapara. Their estimate for Pilhibit Forest Division was zero, contra Johnsingh et al. (2004). Biswas’s study also considered that Hog Deer had been lost from 35 historically known localities, and suggested it was ‘endangered’, with citations given for alarming decline even prior to the mid 1970s (Biswas 2004). The figures were not derived from rigorous sampling and some will surely need revision. Particularly, it is certain that there are over 10,000 Hog Deer in Kaziranga, with a best estimate of 14,000–16,000, at ecological densities of 38.6 (with SE 3.45) animals per km2 (Karanth and Nicholls 2000, N.S. Kumar pers. comm. 2008); and in Corbett Tiger Reserve, only about 100 were reported in 2008 by Bivash Pandav (pers. comm. 2008) and while the actual number is unclear, densities are now very low, even in prime habitat (K.M. Chinnappa and Praveen per N.S. Kumar pers. comm. 2008), and a rapid decline is in place (A. Kumar pers. comm. 2008). Dudhwa Tiger Reserve also faces a suite of conservation problems meaning that population status of Hog Deer there is unlikely to be as healthy as in Kaziranga: poaching is rampant, and the creeper Tiliacora acuminata is proliferating across Hog Deer habitat (Kumar et al. 2002, Johnsingh et al. 2004, N.S. Kumar pers. comm. 2008). At Jaldapara Wildlife Sanctuary, where Biswas (1999) studied ecology of Hog Deer in the 1990s, sightings, and presumably populations, have now drastically declined (A.J.T. Johnsingh pers. comm. 2008). Hog Deer is now primarily restricted to protected areas (A. Choudhury pers. comm. 2006), but south of Rajaji National Park there are a few isolated groups along the river (perhaps totalling about 100 animals); these are outside protected areas (B. Pandav pers. comm. 2008). All such subpopulations outside protected areas are in very rapid decline (N.S. Kumar pers. comm. 2008). The presence of this species in Manipur and southern Assam (close to Manipur, Mizoram and Tripura) is based on records in Biswas et al. (2002); its current status there is unknown. All groups in these areas were estimated to be very small, and should not be assumed to persist. The more recent assessment by Choudhury (2013) indicated the following numbers in some key northeastern Indian reserves: Kaziranga (c. 10,000; marginal decline owing to high floods), Manas (c. 1,500; marginal increase since near extirpation in the 1989-1992 period), RG Orang (c. 500; all in Assam); Jaldapara (250+; marginal increase in recent years owing to improved protection, in Arunachal Pradesh); and Keibul Lamjao (c. 100) (in Manipur).
Bangladesh
Hog Deer has disappeared from the Sundarbans (Salter 1984) and has not been reported from the Sylhet District, in the northeast, since the 1970s (Khan 2004). After a long period with no records, an animal was trapped by local people in 2002 (Khan 2004). Further surveys suggested that a few Hog Deer remained in the Chittagong Hill Tracts of the southeast (Khan 2004, Md Anwarul Islam pers. comm. 2008). Camera trapping and observational surveys during 2010-2011 in Chittagong Hill Tracts did not detect Hog Deer, however the surveys did not cover the low hills and degraded forest areas in which the species would most likely be expected to occur (S. Chakma per.comm. 2014). There is a small captive population derived from native animals (Md Anwarul Islam pers. comm. 2008). Within historic times, Hog Deer was never widespread in the country and pressure was on it from at least the 1970s (Md Anwarul Islam pers. comm. 2008).
Nepal
Hog Deer is locally abundant in the Terai, but is now restricted largely, if not entirely, to protected areas (P. Yonzon pers. comm. 2006, H.S. Baral pers. comm. 2008). Although subpopulations may currently be relatively stable, declines in the past 20–30 years are likely to have exceeded 30% (H.S. Baral pers. comm. 2008). Measured densities range from 0.1 per km2 in riverine forest, to 16.5 per km2 in savanna, and 35 per km2 in grassland flood-plains (Seidensticker 1976, Dhungel and O’Gara 1991). In Bardia National Park, densities of 77.3 animals per km2 in the floodplain association and 5.8 animals per km2 in the riverine association (and zero in Sal forest) were measured (Odden et al. 2005). The species occurs in the following protected areas: Parsa Wildlife Reserve (with a very small subpopulation), Koshi Tappu Wildlife Reserve, Bardia National Park, Chitwan National Park, and Sukla Phanta Wildlife Reserve (Hem Sagar Baral pers. comm. 2008). Each of Suklaphanta, Bardia and Chitwan supports hundreds of Hog Deer. As of 2014, there has been no significant change in the population since 2008 (H.S. Baral pers. comm. 2014).
Bhutan
The small Bhutan subpopulation is found mostly along the southern foothills and small plains along the rivers. Animals have been observed in three protected areas along its border with Assam India, these are Phipsoo, Royal Manas and Khaling. The number of individuals in Royal Manas National Park could be greater than 150, with the grassland around the Gabhorukunda river as the main stronghold (A. Choudhury, pers. comm 2014). It has also been recorder from Mochu Wildlife Reserve.
China
Hog Deer historically was recorded in southwest parts of Gengma and Cangyuan counties of Western Yunnan bordering Myanmar, and has recently been stated to be extinct in the country (Ohtaishi and Gao 1990, Smith and Xie Yan 2008).
Myanmar
Hog Deer has long been known in Myanmar (e.g., Evans 1902) and occurred throughout the country wherever there were grassy plains (Peacock 1933). For the 2008 assessment detailed information on Hog Deers current range or population status in Myanmar has not been traced. It was already in major decline by the time Peacock (1933) wrote. It was listed only for three protected areas by WCMC (1992): Pidaung, Kahilu, and Hlawga Wildlife Reserves. Of these, the Hlawga subpopulation of many dozen (in 2007) is a semi-captive, managed herd: the entire area, of several square kilometres, is fenced; however, it may be ‘native’ in that the founders were reputedly from animals captured locally during the 1980s (Saw Htoo Tha Po verbally 2007 to J.W. Duckworth pers. comm. 2008)., but these have been added to over the years (T. Zaw pers. comm. 2014). As of 2014, there were still small numbers at Hlawga, but they appeared to be decreasing because of new management at the park and possibly hunting (T. Zaw pers. comm. 2014). The Pidaung Wildlife Sanctuary was set aside in 1918 to protect an unusual mix of evergreen forest and savanna-like ecosystems (Milton et al. 1964), and Hog Deer used to be very numerous within it (Peacock 1933); at this time it was the only site in the country where Hog Deer received a measure of protection. Today, the presence of permanent human settlements, roads and railway lines, plantations of sugar cane, military camps and permanent cultivation have completely altered large portions of the sanctuary, and an insignificant area of the original ecosystem remains (Rao et al. 2002). These land-uses are concentrated in the plains parts of the sanctuary, where Hog Deer used to live, and have converted so absolutely these areas that it is not obvious to someone driving along the road when the protected area is entered or exited (J.W. Duckworth pers. comm. 2008, based on visits in 2005-2006). People and dogs are ubiquitous and it seems implausible that any Hog Deer could survive here (J.W. Duckworth pers. comm. 2008, based on visits in 2005–2006). However park staff believe that a few animals still persist there (T. Zaw pers. comm. 2014). In 2010 and 2011 Hog Deer was confirmed by camera-trapping from Hukaung Valley in Kachin state (T. Zaw pers. comm. 2014), following on from reports from hunters and conservation staff between 2005-2007 (J.W. Duckworth pers. comm. 2008). At the turn of the century suitable habitat was very extensive in the Hukaung Valley, but as of 2014 review of remote imagery suggests that there has been massive loss of riparian grasslands to make way for agriculture and other anthropogenic land uses (R.J. Timmins pers. comm. 2014). Hog deer are still present in a fairly large area of floodplain grasslands including areas along the Tanai (Upper Chindwin), Tawan and Mogaung streams. Much of the grasslands where hog deer area known are outside of the Wildlife Sanctuary but as awareness of the species is increasing, it appears they occur further inside the Wildlife Sanctuary than previously thought (R. Tizard pers. comm. 2014). An FFI survey team recorded Hog Deer in the grasslands between the boundary of Indawgyi WS and the forest in 2012 (T. Zaw pers. comm. 2014). Several government staff indicated in 2005-2007 that the species is still locally common in lowland Myanmar (J.W. Duckworth pers. comm. 2008). Pidaung was seen as a flagship protected area (it was one of the country’s first), and its current status does not augur well for the few other protected areas which contain suitable Hog Deer habitat. Extensive camera-trapping for a Tiger survey found no evidence of the species (Lynam 2003), but this may simply have reflected the focus of the survey on closed evergreen forests (habitats unsuitable for Hog Deer), as various other species known to be common but not using closed evergreen forest were also camera-trapped rarely if at all (T. Zaw et al. 2008).
Thailand
The species was formerly abundant in the Chao Phraya Basin during the early 20th century, but had become extinct there by the mid-1960s (Humphrey and Bain 1990). There was formerly a huge export trade, for example 20,000 skins went out of the Gulf of Siam (it is not stated whether this was from Thailand, Cambodia, or both) in 1930–1931 (Dumas 1944). There was a plea for conservation attention to the species in Thailand in Lekagul and McNeely (1977), but this seems to have come too late. Animals reportedly from Thailand and possibly Myanmar have been used to build up numerous managed herds in captive and semi-wild conditions across the country, although the origins of the managed herds remain uncertain. Such animals were introduced into Phu Khieo Wildlife Sanctuary and Propagation Station in northern Thailand in the early 1990s, at a higher elevation than is typical for the natural range of the species; this herd lives in open grassland around the edge of a reservoir (A. Pattanavibool pers. comm. 2006, R. Steinmetz pers. comm. 2006). There is also an apparently large introduced subpopulation on the island of Ko Chang in the Gulf of Siam.
Lao PDR
Hog Deer is probably extinct in Lao PDR and its past status is difficult to assess: there are few, if any, specimens held in international collections from the country, and there were no records (except of old trophies) during extensive surveys across the country in the 1990s (Duckworth et al. 1999). However, Osgood (1932) specifically cautioned that it was much under-represented in zoological collections, despite it being locally common in Indochina. The extent to which this statement includes Lao PDR is unknown. All potentially suitable habitat patches are now small in size and are heavily used by local people, hunting pressure in Lao PDR is high, and it is inconceivable in the great majority of areas that any Hog Deer could still persist (R.J. Timmins pers. comm. 2008, 2014).
Viet Nam
Hog Deer is thought to be extinct in Viet Nam, having previously occurred in some large subpopulations in suitable habitat (e.g. Clark undated) and apparently having been widespread in the south according to reports in Ratajszczak (1991). This reflects the rapidity with which suitable habitat has been lost and the heavy hunting pressure on large mammals throughout much of Viet Nam (Tordoff et al. 2005, Timmins and Duckworth 2000). If the species still occurs in Viet Nam, it is most likely to be along the Kon river in Kon Cha Rang Nature Reserve, the western Srepok river lowlands of Dak Lak Province, the Sa Tay area of Kon Tum and Gia Lai Provinces, the Dong Nai river lowlands and Lam Dong Province (R.J. Timmins pers. comm. 2008). However, there is no recent evidence other than unconfirmed reports, and a trophy which may be of Hog Deer from the Kon Cha Rang NR area. Other evidence, notably high hunting rates of ungulates in general, suggest that even very small numbers are unlikely to survive (Dang Huy Huynh 1986, Tordoff et al. 2005, R.J. Timmins pers. comm. 2006, 2014).
Cambodia
Hog Deer used to be abundant on the vast marshy plains of Cambodia, such as around Sre Ambel, in the province of Kratie, around Kompong Som, and around Kampot; in the drier regions of much of the north it was not common (Dumas 1944). Increased wildlife surveys from 1994 onwards failed to find Hog Deer anywhere in Cambodia until it was re-found in Kratie in 2006, following concerns it might already be extinct (Tordoff et al. 2005, Maxwell et al. 2007). A few animals, probably in the low dozens, remain scattered in small groups in remnant areas of floodplain grasslands and other vegetation in Kratie Province (Maxwell et al. 2007, Bezuijen et al. 2008.). In 2008 the species was detected in grasslands and remained widespread (Timmins and Sechrest 2010). Potential habitat in the southwest was much greater in extent than in the Kratie floodplains suggesting that a much larger subpopulation of deer remained there at least at the turn of the century (R.J. Timmins pers. comm. 2014) and the species was recorded from three additional sites in 2013 during focused surveys for the species (Brook et al. 2015). Since 2008 however there has been no effective protection of any of the known subpopulations or of other areas of habitat with good potential for persistence; and coastal areas have in the intervening six years seen high rates of conversion especially to plantation agriculture and forestry (R.J. Timmins pers. comm. 2014). All remaining subpopulations are likely to be small, possibly isolated from each other, and subject to hunting (Brook et al. 2015).
Sri Lanka (probably introduced)
Hog Deer is restricted to largely cultivated landscapes within a 35 km2 area, between Ambalangoda and Indurawa on the southwest coast, and inland as far as Elpitiya (McCarthy and Dissanayake 1992, 1994). It does not occur in any protected area. Hog Deer is thought to have been introduced to Sri Lanka by the Dutch or the Portuguese in the 16th century, or possibly by a Sinhalese ruler in the pre-colonial period or the British later on; suggestions that it is native are doubted because of the absence of records across central and southern India (Biswas and Mathur 2000). Vishvanath et al. (2014) recommend genetic studies to further clarify the status of Sri Lankas Hog Deer subpopulation.
Australia (introduced)
All extant subpopulations of Hog Deer are on the South Coast of Victoria. There are two managed subpopulations at reserves on Sunday Island and at Blond Bay. Additionally, there are scattered groups on private land between Wilsons Promontory and Orbost. These subpopulations derive from releases made in 1865 (Scroggie et al. 2012).
Current Population Trend: Decreasing
Additional data:
? Population severely fragmented: Yes
Habitat and Ecology [top]
Habitat and Ecology: Hog Deer is usually reported from habitat consisting of wet or moist tall grasslands, often associated with medium- to large-sized rivers (Bhowmik et al. 1999, Biswas and Mathur 2000, Biswas 2004), and appears to reach its highest densities in floodplain grasslands (Seidensticker 1976, Dhungel and O’Gara 1991, Karanth and Nichols 2000, Odden et al. 2005). It avoids closed-canopy forest, but will use coastal grasslands (e.g., Peacock 1933). Johnsingh et al. (2004) considered Hog Deer to be an obligate grassland species in the Terai Arc Landscape of India, and studies in India and Nepal have shown a preference for grasslands dominated by Imperata cylindrica (Biswas 2004 and references therein). Similar alluvial floodplain grassland seems to be used in Thailand and Indochina (Maxwell et al. 2007, Clark undated, R.J. Timmins pers. comm. 2006). In Bardia National Park, measured densities were much higher in the floodplain association than in the riverine association, and no Hog Deer was found in adjacent Sal Shorea robusta forest at all (Odden et al. 2005). In the hilly areas of northeastern India, it occurs in small grassy areas, light woodland and abandoned juhms with grass (Choudhury 2013, A. Choudhury pers. comm 2014). The highest elevation where it has been recorder was 1,500 m asl in Nagaland (Choudhury 2013). These seem to be marginal habitats supporting only low-density subpopulations (A.U. Choudhury pers. comm. 2006): they may historically have been primarily ‘sink’ subpopulations. The remnant population in Bangladesh is located in grassy, lightly wooded, hill country (Khan 2004). In the southwestern coastal lowlands of Cambodia, where apparently the species was once common (Dumas 1944), the species appears to use an open habitat mosaic including brackish Eleocharis sedge marshes and ‘upland’ tall Imperata cylindrica grasslands, and areas of scrubby open secondary woodland interspersed with ‘dry’ short stature grasslands; cane-grass floodplain grasslands are essentially absent in this region (Timmins and Sechres 2010, R.J. Timmins pers. comm. 2014). The reintroduced semi-wild subpopulations in Thailand occupy a variety of habitats for which there is no evidence of use by wild subpopulations in Thailand, Lao PDR, Viet Nam or Cambodia. One of the few detailed historical accounts of an abundant subpopulation in Southeast Asia was from extensive tall floodplain grasslands in the Dong Nai catchment, Viet Nam (Clark undated). Hog Deer is a primarily a grazer of young grasses, particularly Imperata cylindrica and Saccharum spp.; it also takes herbs, flowers, fruits and browse (young leaves and shoots of shrubs; Bhowmik et al. 1999, Dhungel and O’Gara 1991, Bisawas 2004, Wegge et al. 2006). It is much more a grazer and less a browser than is the Sambar Rusa unicolor. Animals occur in scrub and cinnamon gardens in Sri Lanka, where they cause considerable damage to home crops (McCarthy and Dissanayake 1992).
Where undisturbed, Hog Deer tend to be crepuscular, with significant day-time activity and some at night, especially in the hot and wet seasons (Dhungel and O’Gara 1991). In some areas it seems to have become more nocturnal and solitary (e.g., Cambodia; R.J. Timmins pers. comm. 2008), presumably through hunting pressure. The main social group is a female and fawn. When more Hog Deer are together, they do not form a strong "unit", fleeing when flushed in different directions rather than as one. In Chitwan, aggregations of up to 20 animals have been observed feeding on new shoots following fire (Dhungel and O’Gara 1991). In Kaziranga, aggregations of 40–80 animals are frequently seen on grazing grounds created by Great Indian Rhinoceros Rhinoceros unicornis and/or short grasslands near large water bodies (N.S. Kumar pers. comm. 2008, based on observations in 1996). Home ranges vary widely in size, but average about five to 70 ha, depending on how the range is defined (Dhungel and O’Gara 1991, Odden et al. 2005). In Chitwan, Hog Deer is essentially sedentary (Dhungel and O’Gara 1991), but in cultivated landscapes (Sri Lanka) movements are reported to be influenced by agricultural seasons (McCarthy and Dissanayake 1992). Hog Deer moves into higher-lying grasslands in response to monsoon flooding in India, Myanmar and presumably throughout their range (Peacock 1933, Q. Qureshi pers. comm. 1995). The rut is during September–October in Nepal and India and (presumably based on captives) during September–February in China. One to two fawns are born during April–May in Nepal and during April–October in China. Gestation period is 220–230 days (Dhungel and O’Gara 1991, Sheng and Ohtaishi 1993). Fawns wean at six months, reaching sexual maturity at eight to 12 months. The maximum recorded life span is 20 years.
Systems: Terrestrial; Freshwater
Generation Length (years): 7
Use and Trade [top]
Use and Trade: Hog Deer is hunted in various parts of its range. It is hunted for its meat (bushmeat trade), traditional medicinal products and for trophy antlers. It is also possible that hunting could be stimulated by demand for captive animals.
Threats [top]
Major Threat(s): Hog Deer is threatened by hunting and by habitat loss and degradation; much prime Hog Deer habitat had probably been converted well before the 20th century (e.g., Peacock 1933). The balance between these threats and their current severity varies somewhat between ‘South Asia’ (here comprising India, Nepal, presumably Bhutan and perhaps Pakistan) and ‘Southeast Asia’ (here comprising China, Viet Nam, Lao PDR, Cambodia, Thailand and Bangladesh). In 2008 it was considered that there was insufficient information to judge for Myammar into which group it would fit however as of 2014 it is now clear that trends in habitats clearance, hunting pressure and conservation management in Myanmar are very similar to ‘Southeast Asia’ especially Cambodia. Sri Lanka and Australia are considered outside the native range so not covered in detail here.
In the Mekong countries of Lao PDR, Cambodia, Thailand, Viet Nam and also probably China and Bangladesh, hunting has been, and remains, the primary direct threat to the species. In addition to local consumption of meat, the main factor presently driving such hunting is the thriving and probably increasing national, regional and East Asian markets trade in bushmeat, abetted by markets for traditional medicinal products derived from deer species and for trophy antlers (Tordoff et al. 2005, Maxwell et al. 2007). It is also possible that hunting could be stimulated by demand for captive animals, especially from zoos and menageries in Thailand and Cambodia (R.J. Timmins pers. comm. 2008), although as of 2014 this is almost certainly insignificant (R.J. Timmins pers. comm. 2014). The species is apparently easy to hunt compared with other sympatric deer (e.g. Peacock 1933, Dumas 1944), and fawns are likely to be very vulnerable to dogs which almost always accompany human parties during excursions, however, brief, outside farm and residential land, even if these are not for hunting (Tordoff et al. 2005, R.J. Timmins pers. comm. 2008). Hunting itself has been greatly augmented by habitat loss: the vast majority of tall floodplain grasslands have been lost in the region due to the suitability of such habitat for human settlement and agriculture, and only very small patches remain. This huge extent of habitat loss probably occurred largely after Hog Deer had been hunted down to negligible numbers (R.J. Timmins pers. comm. 2008). The coastal lowland open habitat mosaic of southwestern Cambodia in contrast remained extensive and relatively little changed even in 2008, however development pressure in the area has increased enormously in the intervening years, with considerable developments of agricultural and agroforestry plantations (Timmins and Sechrest 2010, R.J. Timmins pers. comm. 2014). Given these threats, which are ongoing, Hog Deer is one of the most threatened large mammals in Indochina (Timmins and Duckworth 2000, Tordoff et al. 2005, R.J. Timmins pers. comm. 2008). The most significant challenge to conserving the species there is the uncertainty involved with long term protected area-based conservation management. As of the end of 2014 there are still no specific conservation measures for the species in Cambodia; none of the known subpopulations occur substantially within a protected area and given hunting pressure and trends in habitat loss, these subpopulations are highly likely to be extirpated in the short to medium term (R.J. Timmins pers. comm. 2014).
Even in South Asia, where many protected areas are effective in conserving populations of large ungulates, Hog Deer declined precipitously in the 20th century through habitat loss and hunting. It is still in decline even within some protected areas (e.g. Bhowmik 2002; see below). In India, habitat loss to cultivation has greatly reduced the area available to Hog Deer, and has continued to do so outside protected areas even in recent decades (N.S. Kumar pers. comm. 2008). Johnsingh et al. (2004) stated that high levels of malaria had previously discouraged settlement, agriculture, and thus habitat conversion in the Terai Arc Landscape, and that the conquering of malaria has made the Indian side of the Terai Arc Landscape "one of the most densely populated regions of [India, with a] population growing at a much higher rate than the rest of [India]. Most of the fertile Terai plains have been taken over by agriculture". Johnsingh et al. (2004) stated that controlling disturbance to Lagga Bagga forest block in Pilibhit Forest Division (now within a tiger reserve; B. Long pers. comm. 2008) is a huge challenge: many people rely on it for firewood, thatch grass and fodder, and that intensive protection and participatory management with these people are required to restore the area. Such a threat profile is typical of areas supporting Hog Deer. Outside protected areas, some Hog Deer remain in woodland areas where densities are very low, and although animals do appear to breed in such situations, it is unclear in the absence of adjacent high-density river plains populations how viable such woodland populations will be in the long term (A. Choudhury pers. comm. 2006). Protected areas are encroached for cultivation and even more so for livestock grazing, which is surely increasing pressure on Hog Deer along with many other species. As a grazing species, Hog Deer numbers are likely to be severely depressed by competition with domestic livestock (by analogy with other wild ruminants, as detailed by Madhusudan 2004), although no data were traced on this. Domestic stock are ubiquitous in all areas outside the protected area network and even occur in many within it, specifically at least: Chitwan; Orang; Jaldapara; and Gorumara (Johnsingh et al. 2004, R.H. Emslie pers. comm., B.N. Talukdar pers. comm., S.S. Bist pers. comm.).
Most subpopulations in India are under severe threat from hunting (N.S. Kumar pers. comm. 2008), although the largest subpopulation of the species, in Kaziranga, has been secured from this threat for many years. Poaching occurs in protected areas throughout the Indian range, especially in north Bengal, and can be associated with other human uses of protected areas perceived to be more legitimate, such as grazing camps (Biswas 2004). Many old skulls of Hog Deer were found across Arunachal Pradesh and Assam during the survey of Biswas et al. (2002). On average two to three skulls were recorded from most houses in villages randomly visited during the survey in Arunachal Pradesh. Regularly, shots were heard and machans (tree-houses made for poaching) were found during the surveys in Nameri National Park, Sonai-Rupai Wildlife Sanctuary and Namdapha Tiger Reserve. According to questionnaire, 52% of responses reported high incidence of Hog Deer hunting in neighbouring areas. Hunting was reported as the primary reason for the sudden decline of the Hog Deer population from north Bengal since 1877. Biswas et al. (2002) detailed evidence of Hog Deer hunting during the survey and past records from the district of Cooch Behar (West Bengal) back to the 18th century. Even today, in high-profile areas such a Corbett Tiger Reserve and Rajaji National Park, there are still instances of deer poaching, and poaching has seriously depleted abundance of large mammals in most of the Terai Arc Landscape. Some poaching is driven by a desire to seek adventure, the thrill of shikar and wild meat, some by crushing poverty of daily wage labourers and others, some to take advantage of the business opportunity of supplying a lucrative trade. Poaching is done with dogs, snares, spears and guns (Johnsingh et al. 2004). Outside protected areas in India, enforcement of anti-hunting regulations is patchy and, unless there is effective specific intervention, all Hog Deer subpopulations in such areas will become extirpated in the near future from hunting (A. Choudhury pers. comm. 2006, N.S. Kumar pers. comm. 2008). Hog Deer avidly eats rice and so in the past was “destroyed ruthlessly on such grounds” (Peacock 1933). It seems unlikely that killing Hog Deer solely for reduction of crop damage is nowadays a reason for population decline, although it may be a convenient excuse to kill deer. Most serious is that the predilection of Hog Deer to eat rice is likely to bring them into closer contact with people and therefore to increase easy opportunities for hunting. In Kratie, Cambodia, Hog Deer occur near, and seasonally forage in, rice fields, especially in the early rainy season. People set traps for wild pigs Sus species, which are more abundant than Hog Deer, and the traps sometimes kill Hog Deer. The local people now are reportedly refraining from using indiscriminate traps in the Hog Deer area, but such cooperation is unlikely to continue forever, because crop predation by pigs is really a problem (A. Maxwell pers. comm. 2008).
In today’s highly fragmented subpopulations which have limited dispersal possibility, flooding may take heavy tolls, especially in the Brahmaputra flood plain (Q. Qureshi pers. comm. 1995). In Kaziranga National Park, where the largest subpopulation of this species is found, flooding is likely to be a major threat: in 1998 the flood reduced the subpopulation to less than half its pre-flood number (A. Choudhury pers. comm. 2006). High floods both lead to drowning as animals are washed away also falling victim to road kill (A. Choudhury pers. comm. 2014). The situation is similar in Nepal where Hog Deer appears to be especially vulnerable because of the short-grass habitats it usually uses during flood season, and in protected area like Koshi Tappu, flooding probably causes wide fluctuations in population numbers (H.S. Baral pers. comm. 2008). Hog Deer subpopulations appear to rebound quickly even from heavy losses, but the fragmentation and increasing isolation of subpopulations into small areas, sometimes with no linkage to suitable higher ground, makes periodic losses from flooding a high risk for future site-level extinctions. Flooding is also a danger because, except in areas of effective anti-poaching activity, by marooning Hog Deer on little patches of high ground it makes them more easy to hunt (Peacock 1933).
A further threat also reflects the colossal habitat fragmentation in recent centuries. Prime Hog Deer habitats are naturally dynamic, and on a living floodplain new areas of grasslands are constantly created through natural processes to replace those changing through natural succession to woody vegetation; creation occurs through traumatic change of floodplain stream and land layout during spates (Dinerstein 1979, Lehmkuhl 1994, Peet et al. 1999). This is incompatible with farming and other human land-uses, which seek a predictable landscape. Hence, within Hog Deer range, there are very few active natural floodplains in which pre-exploitation processes shape the landscape in this way. Thus, the grasslands which are the prime habitat of Hog Deer generally require active management. In some protected areas grasslands are being lost by succession of wooded habitats, for example Chitwan (A. Choudhury pers. comm. 2006) and Bardia (Odden et al. 2005). By contrast, annual burning in Kaziranga, while maintaining a grass habitat, has rapidly changed the grassland structure and composition and how this change affects Hog Deer subpopulations is not known (S. Deb Roy pers. comm. 1996). In Nepal there is also succession of different grassland types and in particular Imperata cylindrica grasslands, which Hog Deer appears to favour at certain times of the year (Biswas 2004), are being replaced by larger cane grasses (H. S. Baral pers. comm. 2008). Locally, conservation management of grasslands to benefit rhinoceroses, for instance in Jaldapara, might negatively affect Hog Deer (Biswas 2004 and references within).
The invasive creeper Mikania sp. threatens Hog Deer’s favoured grasslands both within and outside protected areas, and after flooding and poaching is possibly the next most serious threat to the species in Nepal (H.S. Baral pers. comm. 2008). In combination with invasion by Chromolaena odorata (=Eupatorium odoratum), heavy livestock grazing pressure and invasion of some grasslands by Acacia catechu and Dalbergia sissou, the grassland area in Chitwan has been reduced from 20% to 4.7% of the national park (R.H. Emslie pers. comm.). Mikania sp. are also carpeting large areas of non-forest habitats in the Hukaung Valley, Myanmar (J.W. Duckworth pers. comm. 2008). Lantana camara is also displacing native plants widely, and in Dudhwa Tiger Reserve, the creeper Tiliacora acuminata is proliferating across Hog Deer habitat (Kumar et al. 2002, Johnsingh et al. 2004, N.S. Kumar pers. comm. 2008). In Assam an invasive Mimosa sp. threatens the habitat in sites like Kaziranga and Orang National Parks, whereas in Manas National Park an invasive Lea sp. has become a major threat to the grassland habitat of the hog deer (B. Talukdar pers. comm. 2008).
Floodplain grasslands are strongly affected in their pace of natural succession by water flows and levels, and seasonal patterns in them. Hydropower development changes these parameters and thus threatens habitat, including a project under consideration across the Mekong which would affect the sole known subpopulation of A. p. annamiticus (that in Cambodia), and another across the Karnali river which would modify habitats in Bardia, Nepal (Odden et al. 2005). There have been proposals to dam the Brahmaputra River in Arunachal Pradesh, and should this happen, this could very negatively affect the habitat quality and Hog Deer carrying capacity of major parks like Kaziranga in future (by preventing or reducing the pulse of nutrients brought in by regular large floods, as well as changes in water levels and flows). In Jaldapara Sanctuary, the River Torsa no longer overflows as a result of massive flood-control structures. As a result the water table in the sanctuary is receding and the natural water-bodies and wallow-pools are slowly drying up (S.S. Bist pers. comm.).
Disease epidemics spreading from domestic livestock presumably pose a threat, especially given the close overlap of Hog Deer and domestic livestock in South Asia, the high densities especially of the latter, and the small and localised nature of Hog Deer subpopulations.
In Sri Lanka the continued survival of the introduced subpopulations depends on controlling hunting and maintaining traditional agricultural land use practices. The land is too intensively cultivated for the establishment of protected areas within the range of the species. Threats in the rest of the introduced range are not reviewed here.
Conservation Actions [top]
Conservation Actions: Hog Deer is fully protected in Bangladesh, India, and probably most or all other range states. One subspecies is listed on CITES Appendix I as Axis porcinus annamiticus.
Wetlands, especially floodplain grasslands, have traditionally been ignored by the protected area systems and other conservation initiatives of Lao PDR, Viet Nam and Cambodia (Tordoff et al. 2005, R.J. Timmins pers. comm. 2006). Most of the area supporting the single known subpopulation in Cambodia has been proposed for protected area status, but the situation is complicated by the inclusion of agricultural lands and traditional use areas of local people, and the high human population immediately nearby (Maxwell et al. 2007, Bezuijen et al. 2008); as of 2014 no protected status has been granted to this area (R.J. Timmins pers. comm. 2014). As soon as the subpopulation was found, a small conservation programme with external funding from WWF was started to support a small number of forestry rangers and local guardians to carry out patrolling and community outreach activities, in addition to basic research. These measures ceased due to a combination of factors including lack of funding and motivation in part brought on by the failure to establish the site as as protected area in c. 2008 (R.J. Timmins pers. comm 2014), but may be re-established by WWF with the Forestry Administration (Brook et al. 2015). Probably the bulk of the southwest Cambodian subpopulation lies outside of protected areas, although there was marginal inclusion within one protected area Botum Sakor National Park and the proposed Southwest Elephant Corridor, with confirmed occurrence near to the Dong Peng Multiple Use Area. However, in all of these areas deer are in peripheral areas, while conservation attention, is focused on extensive forest at their heart (R.J. Timmins pers. comm. 2014).
In 2013 a national action plan was developed for the conservation of Hog Deer in Indochina. The plan recommends securing the Kratie subpopulation and one of the Southwest subpopulations (Andoung Teuk) thourgh establishing anti-poaching patrols, engaging local communities in the conservation oh Hog Deer, stabilizing land-use and formalizing protection for the sites. It also recommends the establishment of a conservation breeding programme for the species from ideally to other known small and isolated subpopulations in the Southwest (Forestry Administration, 2014). The plan has not yet been approved by the Ministry of Agriculture, Forestry and Fisheries. To ensure protection and survival of animals, consideration should be given as to whether it would be useful for part of the areas to be strategically fenced to help deter poaching, agricultural encroachment and predation by dogs; but this would need to consider seasonal movements.
There are few areas in Viet Nam where suitable habitat is thought to remain, but if reasonable extents of alluvial grassland survive in the following areas surveys for Hog Deer may be warranted: Cat Tien National Park, the Kon river in the Kon Cha Rang Nature Reserve area, and the Sa Tay area of Kon Tum and Gia Lai Provinces; although given the high hunting pressure in Viet Nam it is becoming very unlikely that any animals could still survive (R.J. Timmins pers. comm. 2014). Cat Tien National Park retains significant areas of alluvial grasslands, and could potentially in the future become a site for reintroduction, however park management appears to be to some extent ignorant of the importance of these grasslands with ongoing schemes to re-establish forest and a fire management policy that is probably leading to woody encroachment of grasslands (R.J. Timmins pers. comm. 2014, based on a visit in December 2013).
It is not certain what conservation measures are in place (if any) for the rediscovered subpopulation in Bangladesh.
There has been no comprehensive assessment of Hog Deer in Myanmar, but it probably exists mostly in unprotected plains grassland areas which, as in the Mekong countries, are conventionally seen as of low conservation value (Peacock 1933, J.W. Duckworth pers. comm. 2006). In 2010 an 11,000 km2 extension of the Hukaung valley was established. Hog Deer were camera-trapped in three localities in the grasslands along the Tawang River; one in the core area and the other two on the edge of the core area and the extension. In the last two years (since 2012) this area has seen the development of human settlements and agricultural expansion (Than Zaw pers. comm.) resulting in considerable loss of grassland habitat (R.J. Timmins pers. comm. 2014). A clarification of the status of Hog Deer in Myanmar is urgent: there may yet remain areas supporting animals which have high conservation potential if they do not disappear before being known to conservation. This lack of conservation profile is the chief challenge to Hog Deer in Myanmar at the moment, as it was in Peacock’s (1933) day: “the butchery of these little deer and the failure to provide more than one small sanctuary for their preservation is certainly one of the weak spots in Myanmar game legislation...the existing legislation is singularly ineffective in preventing their wholesale destruction. Moreover, there are few forest reserves which are suitable for the Hog Deer, and the legislation concerned with such forests is little more than a gesture”. If not met head-on, there are no grounds to assume that Hog Deer national conservation status will not replicate that shown by all range states to the east (major population collapse), if indeed it has not already done so.
Most Hog Deer subpopulations remaining in India, Nepal and Bhutan are in protected areas where animals are at least somewhat, and in some cases well, protected from poaching (Biswas et al. 2002, Biswas 2004, Johnsingh et al. 2004, Pralad Yonzon pers. comm. 2006, H. S. Baral pers. comm. 2008, A. Choudhury pers. comm. 2006, N.S. Kumar pers. comm. 2008). Wildlife protection laws in India have also helped in retaining the specialized habitat of Hog Deer, arresting habitat loss and habitat conversion in some protected areas. Johnsingh et al. (2004) found a strong correlation with Hog Deer subpopulations and protected areas in the Terai Arc Landscape of India (similar to that for Barasingha Rucervus duvaucelii), in contrast to other deer which occur relatively widely outside protected areas. Some protected areas are not big enough to allow adequate ranging during heavy flood periods, and thus prevent heavy mortality during such periods, and all suffer from being too small to be allowed unfettered habitat succession, because new grasslands are not now being created by natural processes elsewhere (see Habitat and ecology). In India and Nepal, Hog Deer has benefited from conservation measures taken for Great Indian Rhinoceros and Barasingha in the same wet grassland habitats (Q. Qureshi pers. comm. 1995, Biswas 2004). However, grassland management for rhinoceros may in some cases be deleterious to Hog Deer (Biswas 2004).
In South Asia there is an urgent need to update the status review of Biswas and Mathur (2000), even though some large Hog Deer subpopulations inhabit some of the best-secured protected areas in the world. Even assuming that these protected areas continue to receive sufficient material and political support, such a review is necessary because all subpopulations face uncertain futures from a multitude of factors, some of which originate outside protected areas and beyond the zone of influence of protected area managers. The review needs to determine roughly the numbers remaining and the locations of all sizeable or potentially sizeable subpopulations, and especially for each make assessments of current and likely future conservation status and population trends, bearing in mind threats from poaching, agricultural encroachment, livestock grazing, natural habitat succession, perverse habitat management, invasive plant species, the risk of disease epidemics from domestic livestock, changes to water levels and flows (e.g. from upstream dams), further fragmentation of subpopulations and habitats, episodic mortality through flooding and abiotic risks such as insurgency (which can collapse protected area management, although it does not always do so). Confinement of subpopulations to small habitat patches isolated from other such patches raises the intrinsic threat of subpopulation loss significantly when considering the wide gamut of threats facing such subpopulations (Biswas and Singh 2002, Biswas 2004), and in some sites challenges may be so pervasive that long-term retention of Hog Deer subpopulations may be so difficult as to be an inefficient use of resources. An integrated South Asia-wide conservation plan may be the best route to direct resources to a representative set of areas where long-term persistence of large Hog Deer subpopulations can be assured provided sufficient resources are mobilised and deployed in the appropriate way.
By contrast, in Southeast Asia, any subpopulation found east of central Thailand (i.e. within the historical range of A. p. annamiticus, the western limit of which is not clear) warrants immediate attention. It is plausible that the recently found small and fragile subpopulation in Cambodia is the last stock of this taxon. The isolated small subpopulations in Bangladesh, although presumably of the nominate race, warrant priority protection in maintaining the ancestral geographic and habitat range of Hog Deer. Species-specific intervention in Myanmar should probably, given the great challenges in the country (and, specifically, the uneven success to date with Eld’s Deer Rucervus eldii conservation), be fitted within larger initiatives such as conservation of the Hukaung Valley, probably the largest floodplain in tropical Asia retaining largely natural ecological processes of stream geography and habitat dynamics.
In Sri Lanka, where the species is restricted to privately-owned gardens, its survival depends on the goodwill of the landowners. The conservation value of this introduced subpopulation needs re-evaluation, considering approximate size, recent trend, ecological integrity and any genetic uniqueness, balanced against the likely cost of conservation interventions to secure the subpopulation’s future. Needs of other introduced subpopulations are not considered here.
There is a large total of animals in zoos of tropical Asia. Although at least one Mekong animal appeared in a zoo recently (in Cambodia in the mid 1990s, C.M. Poole pers. comm. 1998), so far as is known, all captive herds are derived from subpopulations from Thailand and Myanmar and further west. Reintroduction of animals in the range of the nominate, should it be needed, thus has many options. There is no captive buffer for A. p. annamiticus.
Citation: Timmins, R., Duckworth , J.W., Samba Kumar, N., Anwarul Islam, M., Sagar Baral, H., Long, B. & Maxwell, A. 2015. Axis porcinus. The IUCN Red List of Threatened Species 2015: e.T41784A22157664. http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T41784A22157664.en. Downloaded on 17 December 2018.
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