Bubalus quarlesi [Ouwens, 1910].

Citation: Bull. Dépt. Agric. Indes Néerl., 38:7.

Type locality: Indonesia, Sulawesi, mountains of C Toradja Dist.

The taxonomic record (above) is taken from Wilson and Reeder (1993). The taxonomy of the anoas (also known as dwarf buffalos) is still uncertain - including whether there are multiple species or just multiple morphotypes. Two putative species (the lowland anoa, Bubalus depressicornis, and the mountain anoa, B. quarlesi) are presently recognized "in the absence of significant opposing evidence" (Burton, Hedges, and Mustari, 2005). Genetic work has shown species-level variation among anoas, although the interpretation of the results is confounded by potential hybridization among captive animals and a significant overlap among supposedly diagnostic features. B. quarlesi belongs to the subgenus Anoa [Hamilton-Smith, 1827], which some authors argue merits full generic rank (see Nowak, 1991). B. quarlesi is monotypic (Wilson and Reeder, 1993); Burton, Hedges, and Mustari (2005) include Anoa anoa as a synonym to B. quarlesi.

Similar in form to the lowland anoa (B. depressicornis), the mountain anoa is the smallest of the extant wild cattle (Buchholtz, 1990). The body is round and barrel-shaped, and the legs are slender (Buchholtz, 1990). Body length is approximately 150 cm and shoulder height is typically 70 cm (Groves, 1969; Buchholtz, 1990). The discrepancy in reported adult weights is marked; nearly a three-fold difference between the two reported values, and unresolvable due to a lack of published data. Burton, Hedges, and Mustari (2005) provide a comprehensive review of characters for distinguishing B. quarlesi and B. depressicornis (included in the text below), with a note that some specimens shows characteristics of both species.

The coat of adults, especially females, is often thick and woolly - a retention of the fuzzy juvenile coat seen in both anoa species (Groves, 1969). This woolly coat may be shed with increasing maturity, but if it is lost the hair is never as sparse as in B. depressicornis (Groves, 1969). The color of adults varies from dark brown to black, with males generally being darker than females (Groves, 1969; Feer, 1994). Compared to B. depressicornis, B. quarlesi has small and inconspicuous markings (Groves, 1969). The slender legs are brownish black along their entire length, a key distinguishing feature from the lowland anoa, in which the forelegs always have light markings beginning at the knee (Burton, Hedges, and Mustari, 2005). Small white spots may be present just above the front hooves, but they are often difficult to see (Groves, 1969; Buchholtz, 1990). The groin region is lighter in color than the back, but is not white (Groves, 1969). The tail of the mountain anoa is both actually and relatively shorter than that of B. depressicornis, being 14.6-17.8 % of the total length (Groves, 1969; Burton, Hedges, and Mustari, 2005).

There are usually no markings on the face, and there is never any crescent of white on the throat (Groves, 1969; Burton, Hedges, and Mustari, 2005). The ears are small and relatively narrow (Buchholtz, 1990). Skull length has been reported as 244-290 mm (see Burton, Hedges, and Mustari, 2005).

Both male and female mountain anoa possess a pair of straight, conical horns (Groves, 1969; Buchholtz, 1990). The horns of adults can be distinguished from those of B. depressicornis by having a round (rather than triangular) cross-section, although the horn characteristics of juveniles of both species are similar (Groves, 1969; Burton, Hedges, and Mustari, 2005). The horns are smooth, without any marked ridges or external keel (Groves, 1969; Buchholtz, 1990). Relatively short, horn lengths for both sexes vary between 14.6-19.9 cm (Groves, 1969).

The gestation period is reported to be 276-315 days by the National Research Council (1983), although the species of anoa is not specified. A captive female at the Krefeld Zoo in Germany had two calves born 13 months apart (Feer, 1994). Infant mountain anoa are noticeably lighter in color than adults, being born a golden brown and growing gradually redder and then darker brown with age (Groves, 1969; Feer, 1994). Sexual maturity among captive animals is achieved at 2 to 3 years (Semiadi et al., 2008). The life expectancy for anoas is 20-25 years (National Research Council, 1983).

Mountain anoas inhabit primary rainforest, usually in hilly landscapes (National Research Council, 1983; Sugiharta, 1994). Although typically found at elevations of 1,000 to 2,300 meters above sea level, altitude cannot distinguish this species from the lowland anoa (B. depressicornis) as in some regions B. quarlesi inhabits forests near sea level (see Semiadi et al., 2008). Dense forest seems to be preferred, especially habitats with a relatively low density of overstory trees and high diversity of understory vegetation (Foead, 1992 in Semiadi et al., 2008; Sugiharta, 1994). Dominant overstory plants in areas frequented by mountain anoa in Lore Lindu National Park (central Sulawesi) include Castanopsis acuminatissima, Cryptocarya pacifica, Calophyllum soulatrri, Lithocarpus celebicus, and Sagraea glabra, while dominant understory plants include Elastostema lineolatum, Carex verticillata, Axonopus compressus, Panicum trichoides, and Elaphantopus scaber (Sugiharta, 1994). Most of the habitat used by this species can also be characterized by an abundant supply of water and low human activity (Sugiharta, 1994).

This species has no natural predators (Schreiber et al., 1999). B. quarlesi feeds on plants in both forest and open areas, including those created by avalanches and characterized by secondary plant succession (Sugiharta, 1994). Sugiharta (1994) noted 27 species of plants which were fed upon by B. quarlesi in Lore Lindu National Park in central Sulawesi. These included seven grass and grass-like species (Axonopus compressus, Oplesmenus corpositus, Panicum trichoides, Paspalum conjugatum, Carex filicina, Carex speciosa, and Carex verticillata), three ferns (Diplazium repandum, Neprolepis radicans, and Sphaerostephanos unitus), seedlings of three tree species (Castanopsis acuminatissima, Elaeocarpus moribundus, and Calophyllum soulattri), and several forbs (Calamus sp., Homalomena sp., Elaphantopus scaber, Ageratum conyzoides, Blumea balsamifera, Desmodium scorpiurus, Salvia hispanica, Pandanus furcatus, Rubus moluccanus, Solanum involucratum, Elastostema lineolatum, Tetrastigma pedunculare, Deparia patersonii, and Globa strobilifera). E. lineolatum and the three species of fern are fed upon most frequently (Sugiharta, 1994). Dung samples analysed by Green (in Whitten et al., 1987) were composed of 38% woody plants, 9% ferns, 16% broad-leaved plants, 17% grasses and sedges, 5% other monocots, and 13% moss. Anoa are reported to visit mineral-rich hot springs and salt licks - the National Research Council (1983) reports they may drink seawater, which might fulfil their mineral needs in areas without licks or springs.

Observations of tracks indicate that mountain anoa travel singly or in pairs, but never associate in larger groups (Sugiharta, 1994). However, Meijer (1983, in Whitten et al., 1987) reported a herd of five animals on Mount Nokilalai running past his expedition. A pair of mountain anoa is most likely to be comprised of a mother and her offspring, or an adult male and female (Sugiharta, 1994). The National Research Council (1983) reports that B. quarlesi is active primarily in the morning, seeking shelter under shade trees during the afternoon. Sugiharta (1994) found signs of mountain anoa under fallen trees with a diameter greater than 60 cm, in areas under the roots of live trees, and under large overhanging rocks along river banks, which he suggests are used for cover. One individual was observed bedded in Gleichenia linearis at the border between forest and grassland at 0430 hours in Lore Lindu National Park (Sugiharta, 1994). Anoas will wallow and bathe in pools of water and mud (National Research Council, 1983).

Feer (1994) conducted a behavioral study of the mountain anoa, observing a captive pair and their two offspring (one male and one female, both immature) at the Krefeld Zoo, Germany. The results of this study are generalized here, but with caveats regarding the low sample size (four individuals) and non-natural habitat.

Defecation and urination are performed separately in B. quarlesi. Both males and females adopt the same posture when defecating, with the back hunched, hind legs crouched, and tail raised. Urination postures differ between the sexes, with males merely moving their hind legs back slightly, while females lower their rump by bending and spreading their hind legs, elevating the tail so it is more or less horizontal.

The adult male performed several behaviors which Feer suggested might serve to reinforce territorial ownership or the dominance rank within the group. These behaviors included using the horns to thrash bushes and branches, digging up soil with the horns, and scraping the ground with the front feet (typically after smelling the area, and followed about half the time by urinating over the scraped up soil). The hierarchy between individuals was reinforced with dominant individuals pushing the forehead or tapping the horns on the flank or rump of a less dominant animal, resting the chin or cheek on the rump, or placing one (rarely both) forelegs on the body. On the approach of a dominant animal or in response to contact, a submissive animal would adopt a posture with the head stretched low and tilted forward, with the horns pressed close to the neck. A more extreme submissive behavior involved the less dominant animal lying down, pressing the neck and chin to the ground.

Indirect aggressive encounters typically involved posturing and ritualized displays, with one animal lowering the head so that the muzzle was near the ground and forehead nearly vertical. If this posture is returned by the other animal, the two anoas face each other, but rarely approach. This "standoff" behaviour was seen in 18% of aggressive encounters, and is likely a threat used to assert a point but avoid an actual fight. In more aggressive situations, the head is bent further, with the forehead close to the ground and the horns pointed towards the adversary. Aggressive charges are directed straight at the adversary, with the head in a normal position (at the height of the withers) or raised with the ears pointing behind. This is accompanied by short, soft grunts or moos. If the opponent does not flee, the charge ends with a sharp blow. This may be followed by using the forehead to hit the shoulder or flank, or by using the horns to strike at the opponent's belly or flank with upward strokes. Among the four anoa in Feer's study, the adults were more likely to initiate indirect encounters (64%) than full-contact ones, while the two younger animals used direct contact with much greater frequency (95%). Aggressive behaviours initiated by the adult male were directed primarily towards the young male, while the adult female displayed these same behaviours primarily to the adult male. Parallel displays - seen in the majority of the Bovinae - were not observed by Feer, although they may occur in the presence of two adult males.

Males test the receptiveness of females to breeding by using "flehmen" (lip-curl) to expose the scent of fresh urine to the Jacobson's organ. The flehmen position in this species was usually held for seven seconds. (Males occasionally flehmen after licking their penis, while females may perform the behavior to a diverse array of olfactory stimuli). If the female is receptive, the male follows with his head stretched forward at the height of the shoulder and the neck horizontal - a position which allows the male to lick the female's vulva to induce urination. Stamping of the forefeet and raising the neck so that the throat comes into contact with the rump of the female escalate the pursuit. After a continued sexual parade interspersed with testing the female's urine, the male places his chin on the rump of the female and then mounts. During copulation, the head and neck of the male are pressed against the back and shoulders of the female, with the front legs pressed against her flanks. Throughout courting, both males and females make shorts moos.

Solitary play was seen in the form of galloping around or chasing at objects, including birds. Play behaviour with conspecifics was elicited by galloping towards them with wild leaps, or with a shaking of the head with a presentation of the horns. This would lead to play fighting, consisting of head-to-head shoving matches with horns interlocked and heads bent to the ground (and thus facing backwards). Occasionally, the anoas dropped onto their "knees" (carpal-metacarpal joints) when sparring. While fighting, the animals occasionally tried to disengage and butt the flanks of their adversary with their forehead or horns. In doing so, the pair of individuals would end up parallel to each other, circling around. Play combat was sometimes interrupted by face-offs (with the animals standing face to face with their heads lowered to the ground) and by rapid chases. Most play behaviour was observed between the two young individuals. Playful advances by a young male to an adult male elicited a response only rarely, while the adult female (his mother) responded more playfully.

B. quarlesi is endemic to the Indonesian islands of Sulawesi and Buton [Butung] in southeast Sulawesi Province (Semiadi et al., 2008). This species appears to be distributed across most of its known historical range, and is found in several protected areas, including Lore Lindu National Park, Bogani Nani-Wartabone National Park, and Tanjung Peropa Nature Reserve (Semiadi et al., 2008).

Countries: Indonesia (Sulawesi) (Semiadi et al., 2008).

The mountain anoa is classified as endangered [C1+2a] by the IUCN (Semiadi et al., 2008), and is on CITES Appendix I (CITES, 2009). B. quarlesi is fully protected under Indonesian law, although enforcement is difficult (Semiadi et al., 2008). The total population has not been determined (in part due to the difficulties in separating this species from the lowland anoa, B. depressicornis), but is unlikely that the number of mature individuals exceeds 2,500 (Semiadi et al., 2008). There has been a decrease in the range and abundance of this species since the turn of the century, and there is no doubt that they have declined since 1980-2000 (Semiadi et al., 2008). The major threats to the survival of this species are hunting (mainly for meat) and the loss of suitable habitat to agricultural development and mining for gold (Semiadi et al., 2008).

Anoa is the Celebes name for buffalo. Boubalos (Greek) a buffalo. The Quarles mountain range runs through central and southwestern Sulawesi. Although called mountain anoas, these buffalo are not exclusively montane creatures; some have been seen at sea level (Whitten et al., 1987).

French

Anoa de montagne (Buchholtz, 1990, Semiadi et al., 2008)

Anoa de Quarle (Semiadi et al., 2008)

 

German

Berganoa (Buchholtz, 1990)

 

Spanish

Anoa de montaña (Semiadi et al., 2008)