12 The Sulawesi Warty Pig

The Sulawesi warty pig (Sus celebensis) is one of the world's few domesticated animals. It is maintained as a village or household animal in a few areas of Southeast Asia, such as on the Indonesian island of Roti. The common pigs of New Guinea and parts of the Moluccas group are hybrids between this species and the common pig.

Appearance and Size

Sulawesi warty pigs are medium sized, averaging about 60 cm high and 40-70 kg. Boars are larger than females and have longer (10 cm) tusks on both jaws. Boars have three pairs of prominent facial warts: on the snout, the cheek, and on the angle of the jaw. In sows these warts are small or absent entirely.

The animals are usually red-brown with sharply marked white and yellow undersides; older animals have a round white spot (about 3 cm in diameter) on each side of the upper cheek. Piglets have horizontal stripes on the body, which disappear as they mature.

The body is covered with scanty coarse hair, but stiff bristles, which become erect when the animal is alarmed, occur along the mid-dorsal line of the body. The longest and stiffest occur on the head and nape.

Distribution

Native to mainland Sulawesi and certain surrounding islands, the Sulawesi warty pig has been introduced to the Lesser Sunda Islands (Flores, Sumba, Roti, Semau, and Timor), the Moluccas (Malmahera and Buru), and Simaleue, a small island west of Sumatra. In some parts of the Philippines (for instance, Naujan and Mindoro Oriental) the animal either occur naturally or has been introduced.

Hybrids between the Sulawesi warty pig and the common domestic pig occur on New Guinea, Ternate, Morotai, Bacan, Amron, Seram, Kei island, Aru island, and Sulawatti.

Status

In many islands of eastern Indonesia, this species is widespread and common. In a few places it is extremely abundant, particularly at higher altitudes; in others, it has been greatly reduced by overhunting, deforestation, and expanding human settlement.

Overall, however, Sulawesi warty pig populations are declining, probably due to increased hunting and to human alterations of the animal's habitats.

Habitat and Environment

This pig inhabits varied environments, including rain forest, mountain forest, grasslands, and agricultural areas.

FIGURE

 

Biology

Like the common pig, the Sulawesi warty pig has broad dietary preferences. It feeds on roots, fallen fruit, leaves, and young shoots. The bulk of its food consists of vegetable materials, but it also feeds on earthworms, insects, aquatic invertebrates, rats, birds, and even carrion.

The uterus and placenta are anatomically indistinguishable from those of the common pig. The litter size is from 2 to 8 piglets, with an average of 5.

Sows can give birth throughout the year, but usually have their young in April or May. The gestation period is about 4 months.

Behavior

Breeding and farrowing occur in the forest and in open Imperata cylindrica grasslands. The pregnant female makes a nest of grasses, leaves, twigs, and branches, which she collects and places over a hole (approximately 2 m long) that she has previously dug. Here she gives birth.

Foraging is the main activity of the day and usually takes up several hours, mainly in the early morning and evening. In the wild the pigs travel in small groups, the young always traveling with an adult female. On the move, warty pigs feed and rest intermittently.

Uses

As a source of meat the Sulawesi warty pig has been recognized and exploited by local populations since prehistoric times. The presence of feral specimens far outside the pigs' natural range indicates that traders or migrants have long carried it with them on voyages, either as domestic stock or as wild specimens to be released for later capture.

The tusks, which can be carved like ivory, are a resource for local artisans. Wild specimens are suitable for sport hunting.

Potential Advantages

There is a body of unrecorded indigenous experience with this animal as a domesticate, but the information needs to be collected and appraised.

The Sulawesi warty pig may be expected to possess resistance or tolerance to the many diseases prevalent in its native habitat.

There is promising potential for hybridization between this species and domestic pigs, which might lead to the improvement of common pigs in tropical regions.

Limitations

Apart from the unwritten knowledge of the indigenous people who raise the species, very little information is available on the characteristics and management of this animal.

Research and Conservation Needs

The genetic variability within the species, as well as the karyotypic differences with common pigs and other Sus species, should be defined. Further, the hybrid vigor resulting from crossbreeding with other Sus species should be- quantified under controlled conditions. Apart from producing potentially important heat-tolerant livestock, crossbreeding may shed important light on the origins of the common pig in Asia.

The animal's nutritional requirements and reproductive biology also need study.

FIGURE