Wild Asian Water Buffalo (Bubalus bubalis)
During the Pleistocene epoch the genus Bubalus was widely
distributed throughout Europe and southern Asia and contained forms conspecific
with B. arnee. When the climate became drier the genus was restricted to
the Indian subcontinent, mainland South-East Asia, and some of the South-East
Asian islands. In historical times B. arnee ranged across South and South-East
Asia, occurring from Mesopotamia to Indochina (Epstein 1971; Mason 1974;
Remnant populations of Wild Water Buffalo are thought to occur at single sites in each of southern Nepal, southern Bhutan, western Thailand, eastern Cambodia, and northern Myanmar, and at several sites in India: in the Bastar region of Madhya Pradesh, in Assam, in Arunachal Pradesh, and possibly in Meghalaya, Orissa and Maharashtra.
Wild Water Buffalo is believed to be extinct in Bangladesh, Peninsular Malaysia, and on the islands of Sumatra, Java, and Borneo. The domestic form (considered by IUCN as B. bubalis) occurs as feral and domesticated populations worldwide (Grubb 2005).
The situation in Indochina is less certain. Lao PDR, Cambodia, and Vietnam were not included within the range of Wild Water Buffalo given in Corbet and Hill (1992). Free-living buffalo of unknown pedigree occur throughout the region (e.g. Sayer 1983; Laurie et al. 1989; Salter et al. 1990; S. Hedges pers. comm. 2008) but Wild Water Buffalo is probably extinct in Viet Nam and almost certainly in Lao PDR (Groves 1996; Grubb 2005; Duckworth et al. 1999; Tordoff et al. 2005; R. J. Timmins pers. comm. 2008).
The origin and current genetic status of the herds of apparently wild buffaloes in Sri Lanka is uncertain but it is thought unlikely that any true wild buffaloes remain there today. Corbet and Hill (1992) included Sri Lanka within the historical range of wild buffalo, although Ellerman and Morrison-Scott (1951), Gee (1964), and Maia (1970) thought that the Sri Lankan buffaloes were descended from introduced domestic stock. Certain ancient texts seem to support this view (Ashby and Santiapillai 1983). The fact that no buffaloes occur south of the Godavari river in India has also been taken to suggest that Sri Lanka possesses only feral buffaloes descended from introduced animals. However, Deraniyagala (1953), considered that the occurrence of fossil buffalo teeth in the gem sands of the Ratnapura area disproved this view, although it is not clear how old these buffalo teeth are (and Gaur remains found at similar depths in the same area were less than 1,000 years old). Moreover, morphometrics suggest that there was an ancestral population of animals on that island closer to Wild Water Buffalo than to Domestic Water Buffalo (Groves and Jayantha Jayawardene unpublished). Nevertheless, even if the Water Buffalo is indigenous to Sri Lanka the question of whether the free-living herds found there today should be treated as wild B. arnee still arises. In the nineteenth-century, free-ranging herds were common over much of the island’s dry low country but they were nearly eliminated by an outbreak of rinderpest at the end of the century, and for a time their survival was in doubt (Phillips 1935). Phillips reported that small populations might have survived in the hill country but the subsequent intensification of agriculture probably led to their demise (Ashby and Santiapillai 1983). After the rinderpest outbreak buffalo recolonised much of the dry zone but most of them had apparently interbred with domestic stock and in 1953 Deraniyagala wrote ‘[the] relatively purest herds are restricted to Yala Game Sanctuary, but much vigilance will be necessary if this remnant is to be kept free from domestic animals which are now encroaching upon this once inaccessible area’. Woodford (1979) also suggested that the genetic integrity of the wild form has already been lost in Ruhuna. To conclude, even if it is assumed that Wild Water Buffalo once occurred on Sri Lanka it seems unlikely that they survived the rinderpest outbreak and the subsequent genetic swamping by feral and domestic buffalo: consequently all free-living buffalo populations on Sri Lanka almost certainly contain genetic input from domestic or feral stock.
Neither Java nor Sumatra are included within the original range of wild Bubalus arnee as presented in many accounts. Nevertheless Stremme (1911) thought that the occurrence of the fossil B. palaeokerabau in Java made it probable that the buffaloes there belonged to the original fauna of the island (as Cuvier believed). Merkens (1927) also doubted, on historical grounds, the domestic origin of all free-living buffaloes on the island as did Mason (1974) who stated that domestic buffalo were present on Sumatra and Java long before the Hindus arrived almost 2,000 years ago. Moreover Van der Maarel (1932) provisionally regarded the fossil specimens which he obtained from Java (and indeed B. palaeokerabau) as specifically indistinct from modern buffaloes, pointing to a Pleistocene presence of the species on the island (cf. Medway 1972). Corbet and Hill (1992) also thought it probable that wild buffaloes occur on Java and Sumatra. Despite the doubts raised by Van der Maarel and Dammerman there is in fact little doubt that all the apparently wild buffaloes now living on Java and Sumatra are descended from domestic animals, or from Wild Water Buffaloes that have interbred with domestic and/or feral buffaloes (S. Hedges pers. comm. 2008).
Opinion is divided over whether to include Borneo within the historic range of the species. Corbet and Hill (1992) did not list it, and neither Mason (1974) nor Payne et al. (1985) considered it likely that Water Buffalo was part of the indigenous fauna. Lydekker (1898), by contrast, described the small buffalo of Sarawak as a separate subspecies (B. b. hosei), although Mason (1974) thought that Lydekker was probably describing the feral animals which were common there. Cockrill (1968) suggested that traders from the Hindu empire in Sumatra may have introduced the buffalo in the twelfth and thirteenth centuries and he did not think that there was any convincing evidence that would suggest that it was an indigenous species. Nevertheless, animal remains from the Niah caves indicate a Stone Age presence of buffalo in Sarawak (Harrisson 1961). Van Strien (1986) also considered it probable that Bubalus bubalis was part of the original fauna of the island and gave north-west Borneo as its current distribution. Harrisson, however, thought that the wild form was extinct. Feral (and semi-feral) buffaloes were formerly numerous throughout Borneo but the current status of the island’s feral population is poorly known. What does seem certain, however, is that even if the species is indigenous to the island (as seems to be the case) no true wild B. arnee occur there today since they would have been genetically swamped by the numerous feral animals some of which were descended from buffaloes introduced from outside Borneo (S. Hedges pers. comm. 2008).
Bhutan; Cambodia; India; Myanmar; Nepal; Thailand
Bangladesh; Indonesia; Lao People's Democratic Republic; Sri Lanka
The total world population of Wild Water Buffalo is almost
certainly less than 4,000 animals and may well be less than 200, occupying an
area of less than 20,000 km˛. Indeed it is possible that no pure-bred Wild Water
Buffaloes remain. However, these figures are little more than informed guesses,
since any assessment of buffalo numbers is hampered by the difficulty of
distinguishing between free-ranging domestic buffaloes, feral buffaloes, truly
wild buffaloes, and hybrids between wild and other buffaloes. Individuals of
Wild Water Buffalo and Domestic Water Buffalo are difficult to distinguish in
some areas, and some domestic populations may be very closely related to
(perhaps identical to) Wild Water Buffalo, as in Cambodia, where traditional
forms of buffalo husbandry allow herds to range freely in forest areas (Timmins
and Ou 2001; R. J. Timmins pers. comm. 2008). There have been few detailed
analyses of the purity of the presumed remaining Wild Water Buffalo populations,
nor in many cases is it obvious how such an assessment would be made. The
Domestic Water Buffalo occurs as feral and domesticated populations worldwide,
including in sympatry with most remaining populations of Wild Water Buffalo
(Grubb 2005; S. Hedges pers comm. 2008). Some feral and domestic populations may
well have conservation significance, retaining some of the genetic stock of the
wild populations for that particular region, this may be especially true in
Indochina due to traditional methods of Water Buffalo husbandry (S. Hedges pers
comm. 1994, 2008; Timmins and Ou 2001; R.J. Timmins pers. comm. 2008).
In India, Wild Water Buffalo is now largely restricted to Assam, Arunachal Pradesh, and Madhya Pradesh. In Assam, the species is found in and around Manas Sanctuary, Laokhowa Sanctuary, Kaziranga National Park, and Dibru Sanctuary. In Arunachal Pradesh, the species occurs in and around Namdapha Sanctuary. There are two populations in Madhya Pradesh (Bastar district), one in Indravati National Park, and another in Udanti Sanctuary, which might extend into adjacent parts of Orissa. However, most, if not all, surviving populations are believed to have interbred with domesticated and/or feral Domestic Water Buffalo. In the late 1980s, Divekar suggested that there were fewer than 100 truly wild buffaloes left in India (in Madhya Pradesh); and by 1992 the numbers had dropped even further to an estimated 50 animals. However, Choudhury (1994) reported that in the early 1990s there may still have been about 3,300–3,500 wild buffaloes in Assam and the adjacent states of northeast India, plus a small number in Madhya Pradesh. A 1997 CAMP workshop assessed the number of mature individuals in India to be less than 1,500 (S. Hedges pers. comm. 1995). The population data suggest a decline of about 80% between 1966 and 1992 in central India. In northeast India, insufficient data exist to enable trends to be calculated but there is little doubt that the number of true wild buffalo has declined and is continuing to decline as a result of interbreeding with domestic and/or feral buffalo, hunting, and habitat loss (S. Hedges and J. W. Duckworth pers. comm. 2000).
An unknown number of Wild Water Buffaloes, believed to include truly wild individuals, occurs in and around Bhutan's Royal Manas National Park. This is the only subpopulation in Bhutan and is contiguous with that in Manas Tiger Reserve in India.
Kosi Tappu Wildlife Reserve contains the only population in Nepal, where there were 159 wild Asian Buffalo in 2004 but this sole Nepali population is currently seriously threatened (Heinen and Kandel 2006).
There are no population estimates for Myanmar, reflecting a paucity of recent surveys. The extent of suitable habitat means the species could be still extant, and a few wild-living animals independent of human husbandry live in the Hukaung Valley of Kachin state (Than Zaw pers. comm. 2006; Saw Htun pers. comm. 2006; A.W. Tordoff pers. comm. 2006 to J.W. Duckworth pers. comm. 2008 ). Pending further information, these should be seen as likely to be genuinely wild stock or at least if feral, of archaic origin, and so, in either case, of conservation significance.
In Thailand, 40–50 wild buffaloes are reported to occur in the Huai Kha Khaeng Wildlife Sanctuary; this is the only population remaining in Thailand (Rattanawat Chairat in litt. to Anak Pattanavibool pers. comm. 2006). This population may be interbreeding with Domestic Water Buffalo, although individuals can often be distinguished in the field (Anak Pattanavibool pers. comm. 2006). In Thailand, wild buffalo numbers have apparently been relatively stable since the mid-1980s (R. Steinmetz pers. comm. 2006).
The population in Cambodia, which is confined to a small area of easternmost Mondulkiri and possibly Ratanakiri Provinces is very small, with perhaps a few dozen individuals remaining (Timmins and Ou 2001; Tordoff et al. 2005). There has not been any thorough analysis of the purity of these animals (i.e. whether they are truly wild, rather than some mix or perhaps just feral domestic animals), as is the case with most other putative populations of the species (Timmins and Ou 2001; R.J. Timmins pers. comm. 2008).
Before 1999, there was reportedly a population in Mom Ray, Vietnam, but this population no longer exists (Dang Huy Huynh in litt.; Do Tuoc pers. comm. 2006). Rumours still persist of presence in other areas, for example the Satay region (Tordoff et al. 2005; R.J. Timmins pers. comm. 2008). Wild buffaloes of the Cambodian population may wander into western Dak Lak province, but no recent records in Viet Nam have been confirmed to represent wild Water Buffalo (Le Xuan Canh et al. 1997; Eames et al. 2004; Tordoff et al. 2005; R.J. Timmins pers. comm. 2008).
The species was thought to formerly occur in Lao PDR, but the date of extinction is not known (Duckworth et al. 1999).
Population Trend: Decreasing
Habitat and Ecology:
Wild buffaloes are tied to the availability of water:
historically their preferred habitats were low-lying alluvial grasslands and
their surrounds, with riparian forests and woodlands also used (Lydekker 1926;
Prater 1971; Choudhury 1994). In Indochina the species frequented the lowlands
dominated by deciduous forests and with a marked dry season, where it apparently
used small pools and marshes, in addition to permanently flowing rivers (Wharton
1957). Free-ranging domestic animals continue to live like this today; in such
areas buffalo retreat to the vicinities of larger more permanent waterbodies
during the height of the dry season, but move widely through the forests at
other times of the year (Timmins and Ou 2001; R.J. Timmins pers. comm. 2008).
Before their major population decline, wild buffaloes were known to make long-distance movements with season, such that when an undoubted wild buffalo turned up in Panna district, India, some 225 km northwest of its nearest known present-day occurrence in Raipur district, this was not an unprecedented movement (Hasan 1980; Arun Singh 1980).
The upper elevational limit is difficult to determine, although animals certainly occur down at sea level; it possibly relates to a need for level land rather than preference for lower elevations, thus allowing for plateaux, and wild-living feral buffaloes live up to at least 1,000 m asl in East Java (S. Hedges pers. comm. 2008).
Little has been published on the diet of wild (or feral) Water Buffaloes. They are probably grazers by preference, feeding mainly on grasses when available, but they also eat herbs, fruits, and bark as well as browsing trees and shrubs. Daniel and Grubh (1966) listed Cynodon dactylon, Themeda quadrivalvis, and Coix sp., as grasses known to be eaten by wild buffaloes in India. They also saw them feeding on the sedge Cyperus corymbosus. Dahmer (1978), Shrestha (1981), and Hiralal Prasad Kushwaha (1986) provided a little information about the diet in Nepal. Wild Buffalo also feeds on crops, including rice, sugar cane, and jute, sometimes causing considerable damage (Lekagul and McNeely 1977; Hiralal Prasad Kushwaha 1986; Bauer 1987b).
Wild Water Buffalo can be both diurnal and nocturnal. Typically, it forms maternal groups of loosely structured herds, typically containing 10–20, but up to 100, individuals, year round. Adult males form bachelor herds of up to 10 individuals, with older males often solitary. The species exhibits a polygynous mating system, with females typically giving birth to single offspring, although twins are possible. It is a seasonal breeder in most of its range, typically in October and November, however, some populations breed year round. Its gestation lasts 10-11 months, with an interbirth interval of one year. Age at sexual maturity is 18 months for males, and three years for females. The maximum known lifespan is 25 years in the wild (Nowak 1999).
Systems: Terrestrial; Freshwater
The most important threats to Wild Water Buffalo are
interbreeding with feral and domestic buffalo, hunting, and habitat
loss/degradation. Diseases and parasites (transmitted by domestic livestock) and
interspecific competition for food and water between wild buffalo and domestic
stock are also serious threats. The scale of the threat posed to Wild Water
Buffalo by the trade in wildlife products is difficult to quantify, not least
because it is unclear how many of the trophies from reportedly wild buffalo are
in fact from wild buffalo rather than from feral or hybrid animals (Divekar and
Bharat Bhusan 1988; Heinen 1993; Choudhury 1994; S. Hedges pers. comm. 2000).
Most of the species' former lowland habitat has been lost to agriculture, and what remains is highly fragmented. However, especially in countries such as Cambodia and Lao PDR, vast tracts of suitable lowland forest remain from which the species has long since been hunted out, and certainly there are several viable tracts of habitat in which the species could be re-introduced (Tordoff et al. 2005; R. J. Timmins pers. comm. 2008).
The Cambodian population is under severe threat from hunting for trophy horns both by Cambodians and Vietnamese hunters crossing the border (Timmins and Ou 2001; Tordoff et al. 2005; R.J. Timmins pers. comm. 2008; Do Tuoc pers. comm. 2006). This threat is currently somewhat alleviated through to an active protected area management project, but hunting is still rife in much of the surrounding area, as is forest fragmentation due to human population in migration, infrastructural developments (especially roads), commercial agricultural expansion, economic land speculation and mineral extraction (Tordoff et al. 2005; R. J. Timmins pers. comm. 2008). However, the most significant threat to the area is the long-term uncertainty of continuation of effective conservation management of the Srepok Wilderness Area. This area faces an uncertain future. with part already degazetted from conservation status and the possibility that more would be excised in the future, the lack of long-term security of external funding adequate to maintain high standards of management, the uncertainty of long-term political support to uphold high protection standards and the uncertainties of maintaining a motivated and well-trained staff (R. J. Timmins pers. comm. 2008).
In Myanmar, the population of wild-ranging buffaloes either truly wild or at least living outside human custody for a long time in and around the proposed Hukaung Valley Tiger Reserve faces a very uncertain future. The seasonally-flooded plains, a matrix of grass and scrub, lies largely outside the already-established Hukaung Valley Wildlife Sanctuary and the areas of highest conservation significance lie south of the boundary even for a vast proposed extension to form the Hukaung Valley Tiger Reserve. All level areas in this region are under very high threat for conversion to agriculture, both rice and industrial-scale plantations of cash-crops. There is also an active hunting system for wild meat to feed hundreds of thousands of itinerant labourers in this area (J.W. Duckworth pers. comm. 2008).
The invasive Mikania sp. also potentially threatens wetlands in the South Asian range of wild Water Buffaloes (Hem Sagar Baral pers. comm. 2008).
Hydropower development and resulting changes in water flow and level conditions downstream also threaten the ecological maintenance of floodplain areas (Odden et al. 2005).
Disease epidemics spreading from domestic livestock presumably pose a threat, especially given the close overlap of Wild Water Buffalo populations and domestic livestock in South Asia, the high densities especially of the latter, and the small and localised nature of Wild Water Buffalo populations.
Wild Water Buffalo is included in CITES under Appendix III
(Nepal). It is legally protected in Bhutan, India, Nepal, and Thailand.
The Cambodia population was a major factor in the decision to place further
protection on the area, now designated as Mondulkiri Protection Forest, and a
significant factor in the decision to establish the Srepok Wilderness Area
Project of the Cambodian Department of Forestry and WWF (Goodman et al. 2003; R.
J. Timmins pers. comm. 2008).
Most of the known populations are within protected areas. In Myanmar, which retains true lowland floodplains in near-natural state in the Hukaung Valley, the protected area system originally almost entirely excluded floodplain grasslands. The inclusion of some areas is now under consideration, and would benefit this species. However, the outcome is far from certain (J.W. Duckworth pers. comm. 2006).
Most remaining populations still require protection from hunting (especially those in Thailand and Cambodia, and Myanmar if still extant), but probably the greater threat in South Asia is protection from contact with other domestic bovines, especially Domestic Water Buffalo.
There is an urgent need to evaluate the integrity of wild-living buffalo populations, including those generally taken as being truly wild and those living as wild animals within the native range, using habitat typical of wild animals, and which have lived outside even occasional husbandry for a long time, in order to determine populations of conservation priority. This should involve the assessment of the relationship of such populations in the context of obvious domestic lineages, especially those in close proximity to wild populations. Such an approach should use multiple genetic markers in addition to an assessment of morphological characteristics.
Surveys to investigate current status of wild-living populations are needed in Myanmar and perhaps the Satay district of Vietnam.