Sus ahoenobarbus, 1758

Don E. Wilson & Russell A. Mittermeier, 2011, Suidae, Handbook of the Mammals of the World – Volume 2 Hoofed Mammals, Barcelona: Lynx Edicions, pp. 248-291 : 285

12.

Palawan Bearded Pig

Sus ahoenobarbus

French: Sanglier de Palawan / German: Palawan-Bartschwein / Spanish: Jabali barbudo de Palawan

Taxonomy. Sus barbatus ahoenobarbus Huet, 1888,

“Palauan” (= Palawan).

Sus ahoenobarbus was originally described as a subspecies of the Bearded Pig (S. barbatus ), but was upgraded to full species because ofits distinct characteristics. A phylogenetic analysis based on two mt DNA cytochrome b fragments (mtDNA cyt b) pacha that S. ahoenobarbus was more closely related to the Visayan Warty Pig (S. cebifrons) than to S. barbatus , of which it was originally thought to be a subspecies. Morphologically it is, however, more similar to S. barbatus , as evidenced by their conspicuous beards and absence of the prominent manes and mandibular facial warts characteristic of Philippine Warty Pigs (S. philippensis). Also, the chromosome number, which is 38 in S. ahoenobarbus, S. barbatus , and almost all other Sus species, but is 36 in S. cebifrons and S. philippinensis, suggests a closer affinity to S. barbatus . As was stated in the taxonomic review of the species by C. P. Groves, “there is absolutely no doubt that this form is a dwarf barbatus .” In view of more recent evidence, it is unclear whether there are issues of data interpretation underlying this apparent contradiction in phylogenetic affinity, or whether there is another explanation. For example, hybridization may have occurred between barbatus and cebifrons, so that ahoenobarbus maintains characteristics of both species. Until further research is conducted, the phylogenetic affinities of S. ahoenobarbus remain unclear. Monotypic.

Distribution. Palawan and associated Is (Calauit, Busuanga, Bacbac, Coron, Marily, Culion & Dumaran, Linapacan in the N, and Bugsuk, Balabac & Ramos in the S). Probably now extinct in Bulalacao.

Descriptive notes. Head—body 100-160 cm, tail 15-25 cm, shoulder height 100 cm; weight up to 150 kg. This species is smaller than S. barbatus , and has a shorter facial skeleton. The hair is thin, bristly, and blackish-brown over most of the animal, but adults have a distinct mane of longer whitish hairs extending from crown to rump and a characteristic beard of long white hairs on the cheeks and jowls that extends in a band across the snout. This band with black hairs around the eyes, forehead, and more anterior parts of the snout, provides a mask-like appearance. Infants lack manes and beards and are generally far less distinctly marked, except for three horizontal bands of orange-colored hair extending from their necks to their hindquarters; the lower band is much broader and extends over most of the lowersides of their bodies.

Habitat. It occurs in a variety of primary and secondary habitats, ranging from lowland and mid-montane rainforests (0—c. 1500 m above sea level) to drier open woodland and grasslands. It also frequents drier limestone and mangrove forests in coastal areas and occurs in cultivated and managed areas.

Food and Feeding. Although this has not been studied,it is thought that ecologically S. ahoenobarbus is similar to the Bearded Pig from Borneo, which consumes roots, fungi, invertebrates, small vertebrates, and a great range of plants, especially favoring lipidrich fruit of the Fagaceae and Dipterocarpaceae families.

Breeding. Nothing is known.

Activity patterns. Little is known, except that the species is most often seen or reported to be active in the early mornings and late afternoons in relatively undisturbed areas, but tends to be almost exclusively nocturnal in areas where hunting and other anthropogenic disturbances are commonplace.

Movements, Home range and Social organization. Almost nothing is known. Most local hunters and other informants report that they seldom see more than two or three individuals together, though it is likely that larger natal family units and other socioreproductive groups are maintained in less disturbed areas.

Status and Conservation. Classified as Vulnerable on The IUCN Red List. This species is endemic to the Philippines, where it is restricted to the “ Palawan Faunal Region,” which extends from Balabac and associated islands in the extreme south-west through all of Palawan Island and its associated offshore islets, as far as the Calamian Islands in the extreme north-east. However, this region also constitutes the easternmost extension of the Sunda Shelf and was intermittently connected by land bridges to Borneo by sea level changes during consecutive Pleistocene glaciations. The species remains relatively widely, if increasingly patchily, distributed. It is heavily hunted throughout most of its range, either for direct consumption or to be sold. One kilogram of pork fetches a price of about twice the price of domestic pork. Pigs are hunted throughout the year, but especially during forest tree-fruiting periods (no specifics are known) when pigs gather to forage on fallen fruits. They are also killed in reprisal for their occasional raids on neighboring forest gardens or other cultivated areas. Hunting methods include snares, low caliberrifles, and small, baited explosive devices known as “pig bombs,” which are made of ping-pong-ball-sized mixtures of gunpowder and shards of porcelain, coated with fish paste or other strong-smelling baits to entice the pigs. These are buried on pig trails or around cultivated plants close to forest edges. They explode when they are unearthed and bitten into by foraging pigs,killing the pigs or, more likely, causing horrendous wounds and producing trails that hunters with dogs can follow to collect the dead or dying animals the following day. S. ahoenobarbus is also threatened by encroachment into forest areas, because ofillegal “kaingin” (slashand-burn agriculture), mining, and other commercial developments. The species is legally protected by Philippine wildlife protection legislation. However, implementation of such legislation is generally poorly enforced and/or realistically unenforceable in most areas—including most designated protected areas. Priority requirements therefore include the more effective implementation of existing legislation and the addition of new protected areas, which should be designed to enable greater management by local governmental authorities than is the case under the existing national system. Awareness campaigns are also important: few hinterland communities are aware of any prevailing wildlife protection legislation, or disregard the laws because of the chronic lack of enforcement by salient governmental authorities. This is especially the case where reprisals against the pigs follow their occasional raids on crops; the reprisals are likely to illicit sympathy and non-action from the responsible agencies. Farming in protected areas and reprisals against the pigs are justified by claims of poverty and loss of livelihood,in spite of the highly dubious nature of such claims. Many claimants are not economically dependent on hunting, but instead hunt for predominately traditional/cultural and recreational reasons.

Bibliography. Boissiére & Liswanti (2006), Caldecott et al. (1993), Esselstyn et al. (2004), Groves (2001a, 2001b), Heaney et al. (1998), Lucchini et al. (2005), Oliver (1995, 2008), Rabor (1977), Widmann et al. (2008).

Figures

On following pages 10 Phılıppıne Warty Pıg (Sus phı/ıppensıs) Mındoro Wany Png (Sus olıven) 12 Pılawın Bearded Pıg (Sus ıhoanobırbus). 13 Bearded Psg (Sus barbatus), 14 Sulawesı Wany Pug (Sus celebensıs) 15 Javan Wany Pıg (Sus venucosusl. 16 Eurasıan Wıld Pıg (Sus scrola) 17 Pygmy Hog (Porcııla salvımı)

Distribution. Palawan and associated Is (Calauit, Busuanga, Bacbac, Coron, Marily, Culion & Dumaran, Linapacan in the N, and Bugsuk, Balabac & Ramos in the S). Probably now extinct in Bulalacao.