Colours of Wildlife: Bushpig
Created | Updated Nov 5, 2017
Bushpig
Willem is a wildlife artist based in South Africa. He says "My aim is simply to express the beauty and wonder that is in Nature, and to heighten people's appreciation of plants, animals and the wilderness. Not everything I paint is African! Though I've never been there, I'm also fascinated by Asia and I've done paintings of Asian rhinos and birds as well. I may in future do some of European, Australian and American species too. I'm fascinated by wild things from all over the world! I mainly paint in watercolours. . . but actually many media including 'digital' paintings with the computer!"
I have a real character for you this time! It is a Bushpig, Potamochoerus larvatus. It is one of only a few wild pig species living in Africa – the warthog and the giant forest hog are two others. It's scientific name means 'masked river pig'. Bushpigs live in forests and woodlands in southern and eastern Africa; in equatorial central and west Africa they're replaced by the Red River Hog, which I will also feature here soon. Like the river hog, and as indicated by its scientific name, it enjoys the fringes of rivers and wooded valleys.
Porks of Prehistory
As I've already written, but might as well write again, pigs go back a long way. Their earliest ancestors appear to have lived in Asia, between 40 and 50 million years ago. These gave rise to two groups: pigs proper, which spread throughout Asia and to Europe and Africa also, and the peccaries, which spread to North America and only fairly recently invaded South America. The peccaries indeed look very pig-like, to the extent that people who don't know the difference will call them pigs. The differences exist in their feet and in their teeth. No true pigs are originally indigenous to the Americas; pigs now living there, even if wild, are all descendants of pigs brought in by Europeans.
Pigs proper are rather conservative in shape: they have big bodies on fairly short legs; four toes or 'trotters' on each foot, each tipped by a small hoof; large heads on very short, thick necks; large ears, rather small eyes, and often prominent tusks. The tusks in their upper jaws curve upwards, whereas those of peccaries project downwards. In both peccaries and in pigs, the upper and lower tusks grind against each other when the mouth is closed, 'whetting' them so that they're perpetually sharp. This is why pigs are such dangerous animals – when threatened! Pigs are also largely omnivorous, able to take in plant as well as animal food. Thus they have generalized teeth and stomachs, unlike the highly specialized grinding teeth and four-chambered stomachs that the more herbivorous antelopes, deer and other ruminants have. But pigs have their own unique adaptation: the nasal disk, which underlies their characteristic flat snouts. Peccaries have this too, to show that they are indeed close relatives and also indicating that even the very primitive pig-and-peccary ancestors living around fifty million years ago, must also already have had it. This is a circular, cartilaginous disk that swivels on a joint on the tip of the snout bones of the skull. This firm disk is what pigs use to dig into the soil with as they root about. The snout is very sensitive, and they locate buried food by touch as well as by scent. The latter sense is amazingly well-developed in modern pigs, which is why pigs can be used to sniff out truffles – or drugs!
Though a huge diversity of ancient pigs are known, the existing modern pig groups are of fairly recent origin, having diversified especially in Africa over the last five million years. The warthog, for instance, is a fairly recent form. Pigs on the African savannah reached an incredible size, some having rivalled buffaloes or even hippos! Sadly, these giant porkers are now all extinct, the largest remaining one being the still very impressive giant forest hog. Some old Asian pigs were also gigantic, and there was even a group of pigs that had horns – a single bony horn in the middle of the forehead, like an actual unicorn, along with smaller horns above the eyes, thus technically making it a Tricorn Pig. A variety of forest- and savannah-dwelling pigs also lived in Europe in warmer ages of the past. The single surviving wild boar species, still present throughout most of Eurasia, is the ancestor of domestic pigs. In southeast Asia, several other pig species occur, including the extremely weird Babirusas of Sulawesi, which I'll hopefully treat here in time. These, in spite of their weirdness and primitive appearance, are also nevertheless quite modern pigs, not so distantly related to the others.
Fine Swine of the Forests
Bushpigs are pretty much generalized, conservative pigs, compared with whom the Warthog is actually highly specialized. They're very similar to the Eurasian wild boar, which also occurs in Africa north of the Sahara. There are actually some feral pigs in South Africa, but a good look will distinguish the bushpig from them. Bushpigs are actually quite variable in appearance: their body colour can be grey, brown, a rich, reddish brown or even nearly black. But they're always covered in rather long, coarse hair, with that of their cheeks, necks and the midline of their backs being the longest. These 'beards' and 'manes' also tend to be whitish. Bushpigs have large, pointy ears, sometimes (but not always) carrying a fringe of long hairs at the tips. They have short upper tusks, not curving outward like those of the warthogs, but more directly upwards. Distinctively, they have upward-pointing bony ridges, similar to the warthog's 'warts', just above the upper tusks, as you can see in my painting. They're amazingly variable in size too, ranging from 55 cm/22" to 80 cm/32" at the shoulder, and a bodyweight of 45 kg/100 lbs to 150 kg/330 lbs.
You can quickly tell when you're in bushpig country. There will be ridges and mounds of freshly-upturned soil, as if someone's been going wild with a garden spade and fork. These pigs must do a good job at aerating the forest soil and enabling new seeds to germinate! They also are probably important for spreading seeds of forest trees around in their dung. Adult boars will sometimes do damage, lashing with their tusks at tree bark to conspicuously mark them as part of their territory. They also tend to deposit their dung at specific spots or latrines. Sows likely also stick to territories. It is important that they have access to water, and also to mud, since they enjoy wallowing. The mud cools them down and protects them against biting insects and ticks. Bushpigs are not very social the way many antelopes are; a typical unit would be a single adult boar and sow, and their recent offspring. Sometimes there can be an additional adult sow or two, subordinate to the dominant sow, and sometimes they join up into temporary larger groups of up to 40 animals. Males sometimes occur single, or may join into groups of bachelors. They move about mainly at night, and are most nocturnal in areas where they're most heavily hunted by humans. They're very pig-like in their food preferences: they eat bulbs, tubers, roots, mushrooms, fallen fruit, berries picked off bushes, and will gobble up small critters like worms, grubs, beetles, pupae and even small reptiles and amphibians. They've been documented as killing and eating bird chicks, and lambs. They don't actively hunt larger animals, but will avail themselves of carrion if they can find it before something else like a hyena does. They will follow monkeys and baboons, which may drop fruit that they can pick up and eat; or elephants, sometimes eating their dung, since a lot of the food an elephant eats passes straight through it with little digestion.
Like domestic pigs, bushpigs communicate with each other in grunts and squeals. They may roar loudly when fighting. Bushpig battles happen between contending adult males. Regular readers will probably note this theme as familiar: there will be shows before things come to blows. Before there is any physical contact, the two bushpig males will display to each other, lifting their long, furry manes to make them look bigger; wag their tails; champ their jaws; paw the ground; circle each other; or roll around, stirring up clouds of dust. Only if these displays cannot settle who looks the biggest and meanest, will they actually start to fight, and again first just bashing their heads or shoving each other around with their snouts. Those tusks, so short when seen from the outside, are razor-sharp and potentially lethal. Once the fight gets furious they'll stab and swipe at each other; though they have thickened skin around their faces, necks and chest region, they do sometimes mortally injure each other. But of course these tusks are also valuable against their main predators, leopards. Indeed, an adult pig is largely immune to predation, only the young piglets being vulnerable – if not properly attended to by the parents.
These pigs bear their litters at the start of the rainy season. Mating happens four months earlier. Even then, the belligerent behaviour of bushpigs comes to the fore! The male and female 'court' each other by snout-to-snout shoving matches, or bashing their foreheads together, prior to mating. The sow retires to a den which she digs and protects with surrounding and overhanging vegetation, mostly grass, where she delivers her litter of up to ten piglets. Like wild piglets, they are delightfully patterned with light stripes running along their bodies. The dominant boar is very protective of the piglets, and will lead them to feeding areas, and protect them against neighbouring boars or predators. They grow quickly, and are sexually mature by the age of 18 months. But they're usually chased out of their parents' group by the age of six months, at which stage they can form or join new groups.
In South Africa, there are some feral pigs, which is to say descendants of domestic pigs, a different species from the bushpig. Most feral populations are in the Western Cape, well away from the main haunts of the bushpigs further to the north. But there are a few hybrids between feral pigs and bushpigs in the country. Mainly, though, domestic or feral pigs are susceptible to an African swine fever against which the bushpig and the warthog are immune.
In agricultural regions, bushpigs are considered pests, and will uproot and eat just about any crop humans are trying to grow, not to mention garden ornamentals. They're especially fond of sugar cane, which has been widely planted in Kwazulu-Natal. They are therefore heavily hunted. A group of bushpigs, when startled, will scatter in all directions; a cornered bushpig will stand its ground and fight, swiping at attackers using its lower tusks. They swim very well (against myths of pigs not being able to do this) and may flee into rivers when threatened, with only their eyes, ears and snouts protruding. In spite of persecution, they have been able to increase their range and numbers in many regions. They're benefited much from humans wiping out their main predators, leopards. They are also extremely wary and clever, not at all easy to get rid of – but electrified fences may be the best way of keeping them out. They are presently not in any danger of extinction.
