Bubalus arnee (Kerr, 1792)

Don E. Wilson & Russell A. Mittermeier, 2011, Bovidae, Handbook of the Mammals of the World – Volume 2 Hoofed Mammals, Barcelona: Lynx Edicions, pp. 444-779 : 583

7.

Asian Wild Buffalo

Bubalus arnee

French: Buffle d'eau / German: Arni / Spanish: Bufalo de agua

Other common names: Asiatic Buffalo, Indian Buffalo, Water Buffalo ( B. bubalis , domestic form, including breed-groups River Buffalo and Swamp Buffalo)

Taxonomy. Bos arnee Kerr, 1792 ,

India, north from Bengal. Restricted by Harper in 1940 to Koch Behar, India.

Opinion 2027 of the International Commission for Zoological Nomenclature in 2003 retained usage of Kerr's arnee for the Asian Wild Buffalo and Linnaeus’s bubalis for the domestic form; they are considered a single species. The three Asian mainland subspecies ( arnee , fulvus , and theerapati ) show a degree of separation based on multivariate analyses of cranial measurements that mightjustify future rank as distinct species, but the sample size is currently too small. The existence of the Sri Lankan subspecies has been debated, but assessment of cranial and behavioral characteristics by C. P. Groves and J. Jayewardene in 2009 suggests that a pure-bred form of the Asian Wild Buffalo still persists in Yala National Park. Four subspecies recognized.

Subspecies and Distribution.

B.a.arneeKerr,1792—EPeninsularIndiaandSNepal.

B.a.fulvusBlanford,1891—NEIndia&NMyanmar.

B.a.migonaDeraniyagala,1952—SSriLanka.

B. a. theerapati Groves, 1996 — W Thailand and EC Cambodia.

Descriptive notes. Head-body 240-300 cm, tail 60-100 cm; shoulder height 150-190 cm; weight 250-1200 kg. Males are considerably larger than females. Although not as tall or as long, a mature male Asian Wild Buffalo is heavily built and can be larger in mass than other mature male Asian wild cattle such as the Banteng ( Bos javanicus ) or Gaur ( B. gaurus ). In contrast to those species, and more like congeneric Bubalus and African buffaloes in the genus Syncerus , the back of the Asian Wild Buffalo is level, without a pronounced hump. The Asian Wild Buffalo is much larger than its congeners, the Tamaraw ( Bubalus mindorensis ) and the Anoa ( B. depressicornis ). The Asian Wild Buffalo tends to hold its head low, and its ears are large. It does not have a dewlap on its throat like some other wild Asian cattle. Its black to ashy-gray pelage is sparse, with rather long hairs, but many parts of the body are essentially hairless, particularly with age. When dry, the skin color is a dark grayish, but the buffaloes are usually mud-covered, wet, and dark brown to black because they spend most of their time in swamps, rivers, and mud holes. The legs from the knee down may be whitish or yellowish gray, but typically are obscured by mud; the hooves are large and splayed. The end of the long tail is bushy. Both sexes have heavy ribbed horns that arise, mostly laterally, far apart on the skull; they are triangular in cross section, and semi-lunar in shape. Males have the largest and longest horns—said to be the widest-spread of any extant bovid species. Along with their distinct geographical distributions, the four subspecies of the Asian Wild Buffalo can be distinguished by their body size, color, and cranial and horn measurements. Subspecies arnee is relatively small, black with contrasting white below the knees; the tail reaches to the hocks; the muzzle is white. Its skull length is usually less than 57 cm, with large teeth and a tooth row greater than 27% of the skull length; horn spans are 100-120 cm and tip-to-tip distances are less than 80% of the span. Subspecies fulvus is very large, pale gray to brownish-gray; its lower limbs are less white than those of arnee , and the tail falls short of the hocks. Its skull length is usually greater than 57 cm, and the tooth row length is 26-28% of the skull length; the horn span is greater than 110 cm, with tip-to-tip distances as in arnee . The subspecies in Thailand, theerapati, is relatively small, with a skull length less than 57 cm and a shorter tooth row relative to skull length, at 24-27%. Its horn span is usually less than 120 cm and the tip-to-tip distance is 80% of the span. Subspecies migona, from Sri Lanka,is smaller overall than the mainland subspecies, and its horn span is less than 100 cm. The skulls of migona are not sexually dimorphic, as in the other subspecies; their length is less than 57 cm and they have especially small occipital breadths of less than 26 cm (mainland female skulls are greater than 26 cm and mainland male skulls are greater than 28 cm). Most migona lack white markings. Dental formula ofall subspecies is 10/3, C0/1, P 3/3, M 3/3 (x2) = 32. The karyotypes of mainland Asian Wild Buffaloes are unknown, but migona has a diploid number of 50. Domestic derivatives, the “Swamp” and “River” Buffaloes ( B. bubalis ), have diploid numbers of 48 and 50, respectively.

Habitat. The Asian Wild Buffalo is a tropical to subtropical water-dependent species. It is now found only in remnant and widely disjunct riverine areas and associated swamps, lowland grasslands, and lowland forests. Many of these preferred habitats have been usurped for agricultural purposes. They occur at low elevations now, but may have occurred at higher elevations where wetland habitats existed (feral Swamp Buffaloes may occur at elevations of up to 2800 m). In the past, Asian Wild Buffaloes living in regions with pronounced seasonality were likely concentrated around permanent water sources during the dry season and spread out through more forested areas during the wet season, much like feral domestic buffaloes do today.

Food and Feeding. Asian Wild Buffaloes are herbivorous and may be more specialized than other Asian wild cattle, given their preference for aquatic habitats. Presumably they are like their domestic counterparts and other wild Asian cattle, preferring grasses and sedges but also eating fruits, herbs, and bark as needed. Little is known about the diets of the Asian Wild Buffalo, but in one study in India, they ate grasses such as Cynodon dactylon, Themeda quadrivalvis, and Coix species and the sedge Cyperus corymbosus. The Asian Wild Buffalo probably eats more aquatic herbaceous plants than the other species, and it can cause serious damage to agricultural crops, such as sugar cane and rice, which are grown close to their dwindling preferred habitats.

Breeding. Specifics on the breeding of the Asian Wild Buffalo are somewhat limited, and may depart somewhat from domestic derivatives. They are polygynous and timing of the breeding season probably varies by locality, perhaps like the Gaur. In areas with a distinct rainy and dry season, breeding and subsequent parturition are expected to be more seasonal. Observations from Nepal and Sri Lanka indicate that a mature bull tends a small cohesive group of adult females and their offspring throughout the year. As rut approaches, other mature males, some of whom may live alone or in bachelor groups,vie for breeding rights and no doubt challenge group-tending males. Dominance among breeding males is likely established by horn-to-horn combat, but few observations of Asian Wild Buffalo competition exist. Perhaps it is similar to the Gaur, where combat is most common among young males rather than fully mature males. The behavioral repertoire of the Asian Wild Buffalo is no doubt similar to other Asian wild cattle, with males frequently assessing females’ urine and genitals. In domestic forms, the estrous cycle is about 20-21 days, estrus last up to 72 hours, and gestation is said to be the longest of any bovid species at 300-340 days. Females probably breed for the first time at 1-5-2 years of age, giving birth to their first calf in their third year. Females may give birth only every other year and generally have one calf at a time, but twins are not uncommon among domestic forms. Calves are said to be fully weaned by about 6-9 months. The domestic counterparts of the Asian Wild Buffalo may live 25 years in the wild and close to 30 years in captivity. The only record for an Asian Wild Buffalo is from a zoo in Kathmandu, Nepal, where a male acquired as a two-year-old was still living as an 11year-old in 2004.

Activity patterns. Activity of the Asian Wild Buffalo is typical of ruminants, involving alternating periods of foraging and ruminating/resting. Depending on conditions (e.g. temperature and human harassment), they can be diurnal or nocturnal. They are very sensitive to heat, having few sweat glands, and spend a considerable amount of the day in water, at times completely submerged except for their head or muzzle. Asian Wild Buffaloes wallow in mud, and their entire bodies are usually mud-covered, providing a thermal advantage and protection from biting insects.

Movements, Home range and Social organization. Asian Wild Buffaloes are non-migratory and gregarious. Group size is generally about 10 individuals, although larger aggregations can be seen. Female groups appear to be cohesive, with a dominant cow and apparently a mature bull leading the movements and activities of the group. Young males generally disperse from female groups at three years of age and join bachelor groups of about ten individuals, which live apart from female groups. In 1999-2001, the population of Asian Wild Buffaloes in Huai Kha Khaeng Wildlife Sanctuary, Thailand, was estimated at 25-60 individuals, with 20% adult males, 55% adult females, 10% subadults, 10% yearlings, and 5% calves. Group sizes were 2-19 individuals (average of 5-67), although groups greater than 10 were rare. Average density in Thailand was 0-27 ind/km?. No information on movements and home range exists for the Asian Wild Buffalo, but female groups of feral Water Buffaloes in Australia had home ranges of 1:7-10 km®. The Asian Wild Buffalo’s sense of smell and hearing are acute, but its vision is said to be poor.

Status and Conservation. CITES Appendix III ( Nepal only). Classified as Endangered on The IUCN Red List. Most known populations of the Asian Wild Buffalo occur in protected areas, and it is legally protected in Nepal, Bhutan, India, and Thailand. In Cambodia, establishment of the Mondulkiri Protection Forest and Srepok Wilderness Area was motivated, in part, by the imperiled status of the Asian Wild Buffalo. Although largely an educated guess, total numbers of Asian Wild Buffaloes in the isolated populations that remain are likely much less than the purported 4000 and may even be as low as 200 individuals; however, some evidence from north-eastern India suggests that 1000 individuals still occur there. Despite their occurrence in protected areas, the biggest conservation threat to the Asian Wild Buffalo is the genetic purity of the few remaining individuals because of interbreeding with the domestic forms (indeed, some speculate that no genetically pure Asian Wild Buffaloes remain). Feral populations of River and Swamp Buffaloes occur throughout South-east Asia, as well as in Australia. Some genetic evidence from Nepal shows that gene flow is predominately from wild to domestic buffaloes and not the other way around, suggesting that female Asian Wild Buffaloes do not breed with domestic males, perhaps because of their inferior size compared with male Asian Wild Buffaloes. Additional research is needed to establish the genetic integrity and relatedness of extant Asian Wild Buffaloes. Other threats include loss, degradation, and fragmentation of their preferred wetland habitats to agriculture; poaching; and competition and disease transmission with domestic cattle and River and Swamp Buffaloes.

Bibliography. Bongso et al. (1977), Chaiyarat et al. (2004), Choudhury (1993), Daniel & Grubh (1966), Deraniyagala (1953), Flamand et al. (2003), Gentry et al. (2004), Groves (1996), Groves & Grubb (2011), Groves & Jayewardene (2009), Hedges et al. (2008), Heinen (1993, 2002), Heinen & Ramchandra (2006), Lekagul & McNeely (1988), Lydekker (1913, 1924), Prater (1971), Roth & Myers (2004), Weigl (2005).

Figures

1. Gaur (Bos gaurus), 2. Banteng (Bos javanicus), 3. Kouprey (Bos sauveli)

Subspecies and Distribution. B.a.arneeKerr,1792—EPeninsularIndiaandSNepal. B.a.fulvusBlanford,1891—NEIndia&NMyanmar. B.a.migonaDeraniyagala,1952—SSriLanka. B. a. theerapati Groves, 1996 — W Thailand and EC Cambodia .