Potamochoerus larvatus (F.Cuvier, 1822)

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 : 279

7.

Bushpig

Potamochoerus larvatus

French: Potamochere du Cap / German: Buschschwein / Spanish: Potamocero de rio

Taxonomy. Sus larvatus F. Cuvier, 1822 ,

“ Madagascar ” (no exact type locality known).

The species is also present in Madagascar and the Comoro Islands, but the taxonomic situation of these populations is still unresolved as this species is thought to have been introduced there. Two subspecies are sometimes recognized on Madagascar: the nominate form larvatus , described by F. Cuvier in 1822, which lives in Mayotte and the north-west of Madagascar, and the race hova from the east of Madagascar. This may suggest that the species was not introduced by people, or was introduced at different times from different source populations. Until this issue is clarified, we do not here recognize the Madagascar races as subspecies, and thus exclude these populations from the species’ distribution. Three subspecies are recognized.

Subspecies and Distribution.

P. l. hassamaHeuglin, 1863 — EAfrica, withspecimensknownfromEthiopia, SSudan, EDRCongo, Uganda, Rwanda, Burundi, Kenya, andTanzania.

P. l. koiropotamusDesmoulins, 1831 — lowerCongoRiver (leftbank), Angola, SDRCongo, Zambia, Malawi, Mozambique, Zimbabwe, Botswana, Swaziland, andSouthAfrica.

P. l. somaliensis de Beaux, 1924 — Tana, Juba, and Shebelle rivers in NE Kenya and Somalia.

The species is also present in Madagascar and the Comoro Is, but their taxonomic situation thereis still unresolved.

Descriptive notes. Head—body 100-150 cm, tail 30-40 cm, shoulder height 55-88 cm; weight 50-115 kg. Bushpigs have a compact body with short legs, rounded back, and elongated snout. The coatis extremely variable in color, from blond, pale red, or russet up to a dark brown or near-black shade. The color may vary with sex, age, region, or individual, and this significant variation in body color has led to the description of many variant races. It generally has a paler head with white face markings. Body hairs are long and sparse but elongated from the forehead to the tail, forming a white or grayish dorsal crest. It has a long tufted tail. Newborns are dark brown in color with longitudinal stripes or rows of paler spots. Adult males display bony ridges and calluses on the muzzle. Females have six pairs of mammae. There are clear distinctions between subspecies based, for example, on color and average male skull length, but there are also indications that intergradation may occur locally between subspecies. Dental formulais13/3,C1/1,P 4/3, M 3/3 (x2) = 42. The upper tusks are very small (average 7-6 cm), but the lower tusks are sizeable (9-16. 5 cm) and razor sharp. Chromosome numberis 34. The life span is 20 years.

Habitat. The Bushpig is ecologically separated from the Red River Hog (FP. porcus ). Within areas of co-occurrence (like the Albertine Rift), the Bushpig lives at higher elevations and the Red River Hog in lowland forests. Elsewhere, the two species are separated by ecological barriers such as the Congo River. Bushpigs occur in a wide range of forested and woodland habitats, from sea level to montane forest (up to 4000 m on Mount Kilimanjaro), with a marked preference for valley bottoms with soft soils and dense vegetation. There are striking differences in habitat among subspecies, with, for example, the hassama race primarily occurring in upland forest areas and the somaliensis race favoring riverine forests.

Food and Feeding. This species is omnivorous and highly adaptable. It is probably a major seed disperser. Bushpigs consume roots, tubers, bulbs, corn, fungi,fruit, eggs, invertebrates, birds, small mammals, and carrion. In Uganda, Bushpigs were seen following groups of monkeys as they forage and feeding on discarded fruits. They make extensive use of their snouts to root for larvae, worms, and underground plant parts. Locally, Bushpig rooting can leave large areas plowed up and cleared of standing vegetation. In cultivated areas, sounders can do serious damage to crops in a short time.

Breeding. Sexual maturity is reached at 18-21 months. Breeding may take place yearround, but most young are recorded at the end of the dry season or beginning of the wet season. The gestation period is 120-127 days. Just before giving birth, females retire to a sheltered nest or hollow. Most common litter size is 3—4, with a maximum of ten. Newborns weigh 700-800 g. They are weaned at 2—4 months.

Activity patterns. Bushpigs are predominantly nocturnal, resting under heavy thickets of vegetation during the day. Nests for raising young or during rainy seasons are built in the cooler parts of their range. In the southern Cape, South Africa, they tend to be more diurnal during the colder months, suggesting that temperature regulation is a significant factor influencing the rhythm of activity. Mud wallowing and rubbing against trees are also regular activities. Population density is regulated by a wide range of predators including humans, Lions (Panthera leo), Leopards (P. pardus), Spotted Hyenas (Crocuta crocuta), pythons, and eagles. Courageous and dangerous when cornered, both boars and sows defend piglets cooperatively and aggressively. Fighting behavior includes frontal and lateral postures with dorsal crest erected, snout-boxing, and forehead shoving. Bushpigs run fast and swim easily. Their senses of smell and hearing are very good, but eyesight only fair.

Movements, Home range and Social organization. In South Africa, groups occupy spatially exclusive home ranges of 3-10 km? with daily movements of 0-5-6 km. Population densities are 0-3-10-1 ind/km?. They live in family sounders of 6-12 individuals, led by a dominant male, with one or more females and their young. Unlike other wild pigs, adult males play an active role in rearing and defending the young. Other males are aggressively chased off and territorial encounters are characterized by ritualized displays and scent marking. Males disperse from the natal group and old males may be solitary, whereas females remain on their natal home range.

Status and Conservation. Classified as Least Concern on The IUCN Red List as the species is relatively widespread and common and there are no major threats believed to be resulting in a significant population decline. Though the Bushpig is still relatively widespread, its distribution is patchy in certain regions. It is reported to be increasingly rare outside of protected areas, and widely hunted either for subsistence or for commercial bushmeat trade at local, mostly urban markets. It is also hunted as an agricultural pest, or because it is a vector of livestock diseases like African swine fever, nagana (a form of trypanosomiasis), and sleeping sickness. Clearing of forested areas and conversion to cropland have benefited this species in some areas.

Bibliography. de Beaux (1924), Cooper & Melton (1988), Duckworth (1992), Estes (1991), Ghiglieri et al. (1982), Grubb (1993), Kingdon (1997), Laurance et al. (2006), Melton et al. (1989), Nielsen (2006), Nummelin (1990), Seydack (1991, 2008), Skinner et al. (1976), Sowls & Phelps (1968), Stuart (1985), Vercammen et al. (1993).

Figures

On following pages 2 Moluccan Babırusa (Babyrousa babyrussa) 3 Tog an Babırusa (Babyrousa rogeanensıs) 4 Common Warthog (Phacochoorus alncanus) 5 Desert Warthog (Phacochoerus aethıopıcus) 6 Forest Hog (Hylochoerus maınenzhagenı) Bushpıg (Pommochoeıus Iarvalusl 8 Red Rıver Hog (Poramochoerus porcas)

Subspecies and Distribution. P. l. hassamaHeuglin, 1863 — EAfrica, withspecimensknownfromEthiopia, SSudan, EDRCongo, Uganda, Rwanda, Burundi, Kenya, andTanzania. P. l. koiropotamusDesmoulins, 1831 — lowerCongoRiver (leftbank), Angola, SDRCongo, Zambia, Malawi, Mozambique, Zimbabwe, Botswana, Swaziland, andSouthAfrica. P. l. somaliensis de Beaux, 1924 — Tana, Juba, and Shebelle rivers in NE Kenya and Somalia . The species is also present in Madagascar and the Comoro Is, but their taxonomic situation thereis still unresolved.