Aardwolf

Name and taxonomy

The genus name Proteles joins two Greek words that together mean "complete in front". The name refers to the five toes on each front foot, against four on each hind foot. The species name cristata is Latin for "crested" and describes the mane. Scientists place the aardwolf in the hyena family, Hyaenidae, within the order Carnivora. It is the only living species in its subfamily, Protelinae.

Zoologists once gave it a family of its own, Protelidae, because they thought it merely mimicked the striped hyena. A 2021 genetic study found that eastern and southern aardwolves differ enough to count as two species. The American Society of Mammalogists now treats the eastern form, Proteles septentrionalis, as a separate species. Other authorities keep one species and are unsure whether even the two subspecies are valid.

Evolution and relatives

The hyena family has only four living species: the spotted hyena, the brown hyena, the striped hyena and the aardwolf. A 2006 molecular analysis placed the aardwolf at the base of that family tree. It split from the other hyenas early, but fossils and genes disagree on the date by about 10 million years. The aardwolf looks like a small striped hyena, and the two share part of their range in northeast Africa. Some biologists have asked whether this likeness is a rare case of mimicry among mammals. No firm evidence supports that idea.

Like other hyenas, the aardwolf has front legs longer than its hind legs, which gives it a sloping back. Its skull has the hyena shape in miniature, but the teeth behind the canines have shrunk to pegs. That change probably marks a lineage that gave up bone and meat for insects long ago.

Appearance

The coat is yellowish or buff, with black vertical stripes on the body. One or two diagonal stripes cross the shoulders and the hindquarters, and more stripes ring the legs. Below the knee each leg is black, and the bushy tail ends in a black tip. A long mane of coarse hair runs along the neck and back to the tail. The animal raises this mane when it feels threatened, so that it looks bigger than it is. The ears are large and pointed, much like those of the striped hyena.

The head and body measure 55 to 80 centimetres, and the tail adds another 20 to 30 cm. An adult stands 40 to 50 cm at the shoulder. Weight ranges from 8 to 14 kilograms, and a heavy animal may reach 15 kg. Southern animals tend to be a little smaller than eastern ones. The cheek teeth are reduced to small pegs, because termites need no chewing. The canine teeth remain, but the aardwolf uses them for fighting rather than for feeding. Older animals often lose teeth, which matters little on a diet of soft insects. Males and females look alike in colour and size.

Habitat and range

Aardwolves live on open, dry plains and in bush country across eastern and southern Africa. They avoid mountains, dense forest and true desert. They are most common where yearly rainfall falls between 100 and 600 millimetres. Because they depend on harvester termites, they occur only where those termites live. Those termites thrive on heavily grazed grassland, so the aardwolf also does well on farmland.

The species forms two separate populations. One lives in southern Africa, from Angola and Zambia south to the Cape. The other runs from central Tanzania north through Kenya, Ethiopia and Somalia to Sudan and Egypt. Wet miombo woodland lies between the two populations, and no aardwolves live in it. GBIF holds records from 16 countries, most of them from South Africa.

A pair and its latest cubs hold a territory of 1 to 4 square kilometres. Territories in South Africa can be larger, up to 8 square kilometres, where termite mounds are sparse. A territory holds up to ten dens, most of them old springhare or aardvark burrows. The pair uses one or two dens at a time and moves on after about six weeks.

Diet and feeding

The aardwolf eats termites, chiefly of the genera Trinervitermes and Hodotermes. It licks them off the ground with a broad, sticky tongue rather than digging into the mound. The tongue is tough enough to bear the bites of soldier termites. A single animal can take 250,000 to 300,000 termites in one night. It finds a colony by sound, and by the scent that the soldiers release. It swallows a good deal of sand with the termites, which helps grind the food in the stomach.

The aardwolf never destroys a mound or eats a whole colony. It remembers where nests lie and returns every few months. Trinervitermes termites are scarce in the cold of midwinter and at the start of the rains. Southern aardwolves then switch to Hodotermes, a harvester termite that forages in the afternoon. This switch explains why aardwolves sometimes feed by day in winter.

They also take other insects and larvae, and very rarely a small mammal or bird. Contrary to a common belief, aardwolves do not eat carrion. An animal seen at a carcass is picking beetles and maggots off it. They refuse meat unless it is minced or cooked for them. A foraging aardwolf covers about 1 kilometre an hour, or 8 to 12 km on a summer night.

Behaviour and social life

Aardwolves are shy, and they spend the day underground. In summer they leave the den about an hour after sunset and stay out for 8 to 9 hours. In winter they are active for only 3 to 4 hours, often in the late afternoon. They forage alone, because their termite patches are too small to share.

The basic social unit is a mated pair with its most recent cubs. Pair bonds last 2 to 5 years. Both sexes defend the territory and mark its edges with scent. An intruder is chased for up to 400 metres or to the boundary. Fights are rare and happen mostly in the mating season. When two animals do fight, they drop to their wrists and bite at each other's necks. When food is short, the territorial system relaxes, and up to three pairs may share one range.

The aardwolf is neither fast nor a strong fighter. When a predator follows it, it may double back on its own tracks to confuse the trail. If cornered, it raises its mane and can release a foul liquid from its anal glands. Young animals leave home a month or two before the next litter is born.

Communication and senses

Scent is the main channel. Both sexes have anal glands that produce a black paste. They smear it on grass stalks and rocks in streaks about 5 millimetres long. Near termite mounds an animal marks about every 20 minutes. Along the boundary it marks every 50 metres, which can add up to 200 marks in a night. Extra glands on the front feet and the genital pad leave scent too. Pairs bury their droppings in shared middens, which they also mark.

Aardwolves are mostly silent. They call only when startled, stressed or fighting, with clucks, hoarse barks and a kind of roar. A raised mane and a fluffed tail send a visual warning. Cubs practise the tail fluff while they play with their siblings. Sharp hearing and night vision help the animal find termites in the dark.

Reproduction and life cycle

In South Africa mating takes place in late June and early July. Elsewhere the season shifts, so that cubs arrive in the rains when termites are active. A dominant male mates with his own partner and also with the females of weaker neighbours. He pastes scent inside rival territories as the breeding season nears. A female may accept the dominant male, and a litter can have more than one father. Mating itself lasts from 1 to 4.5 hours.

Gestation lasts about 90 days. The female gives birth to two to five cubs, and litters of two or three are the norm. Cubs are born with open eyes and weigh 200 to 350 grams. They stay in the den for the first six to eight weeks. The male guards the den for up to six hours a night while the female feeds.

At three months the cubs start to forage under supervision. Weaning is done by about four months, and the young forage alone from about seven months. They mature at about 18 months to two years of age. No one has measured lifespan in the wild. A captive female lived to about 20 years, and one at Frankfurt Zoo reached 18 years and 11 months.

Predators and threats

Adult aardwolves have no regular predator. Black-backed jackals take cubs when the male leaves the den unguarded. Lions, leopards and larger hyenas probably kill the odd adult, but such losses do not shape the population. Farm dogs trained to hunt jackals attack aardwolves by mistake. Vehicles kill some on roads, though the animals tend to avoid them.

People are the main threat. Some farmers believe the aardwolf kills lambs or poultry and shoot it on sight. Others know better but still kill it now and then for its fur. Insecticide sprayed against termites poisons the aardwolf through its food. Heavy spraying probably also empties a territory of termites and forces the pair to move.

Population and conservation

The IUCN Red List places the aardwolf in the Least Concern category. Numbers appear stable across most of the range. Even so, the animal is never common. Density seldom rises above one adult per square kilometre, even where termites are plentiful. Sightings are rare, because the animal is timid and comes out at night. Botswana lists the species on CITES Appendix III, which regulates trade from that country.

No park or programme exists only for the aardwolf. It gains protection inside reserves across its range, and it does well on grazed farmland. Education campaigns in South Africa tell farmers that the aardwolf eats termites, not stock. Zoos keep the southern form in about 15 collections worldwide. The eastern form is held in a single zoo, in Novosibirsk.

Relationship with humans

The aardwolf is a friend to the farmer. One animal eats up to 105,000,000 termites a year. Harvester termites strip the grass that cattle and sheep need, so the aardwolf protects grazing. It does no known harm to people or livestock. Still, its resemblance to a hyena and its night habits make it a target.

The Afrikaans name maanhaarjakkals, "mane jackal", shows how early settlers saw it. They counted it among the jackals and hyenas that raided the kraal. Its pelt has a small local trade. Zoos in Europe, North America, South Africa and the Gulf keep the southern form. It is unsuited to life as a pet, since it needs hundreds of thousands of live termites a night.

In culture and myth

The aardwolf plays a small part in African folklore compared with the hyena and the jackal. Southern African settlers named it the "earth wolf" for its burrows and its dog-like shape. The name misleads, because the animal is a hyena, not a wolf. Pastoral communities told of night raids on small stock and poultry, and they blamed the aardwolf. Safari guides have a nickname for it, the termite-mound ghost, for its silent moonlit foraging. Its hyena shape earned it the hyena's sinister reputation in some regions.

Modern spirit-animal websites make the aardwolf a symbol of cleverness, patience and finding food in unexpected places. These readings are recent inventions and are probably not rooted in any named tradition. One popular belief holds that the aardwolf eats carrion, which is false. Another says it kills lambs, which it cannot do with its peg-like teeth.