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You are here: Home > Wildlife > Mammals > Black-backed jackal
WILDLIFE: MAMMALS: BLACK-BACKED JACKAL
Class: Mammals
Order: Carnivores
Family: Canids
Genus and species: Canis
mesomelas
Common name:
English: Black-backed/silver-
backed jackal
Swahili: Bweha nyukundu/shaba
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Identification
Body: coat rufous except in the back, which shows a well-defined and contrasted strip of black hair with white tips, giving a silvery aspect at a certain distance. The black strip covers the back from the neck, where it is broader, to the tail. Underparts are whitish. Tail bushy, rufous and with a dark tip. Height at shoulder: 38-48 cm. Length: 90-105 cm. Tail: 32-35 cm. Weight: 10 kg. Males are slightly larger and with a brighter coat. Pups are uniformly coloured, lead grey to dark brown, with belly paler.
Head: shape and look resembling a fox. Sandy tinges in muzzle and cheeks. Ears long and pointed, rufous in colour. Yellow eyes.
Distribution and ecology
The most common of Kenyan jackals, distributed in suitable habitats throughout the country. Inhabits savannah, open plains, scrubland, open forest and semi-desert regions. Occupies mainly the intermediate habitat between the plains, preferred by the golden jackal, and deciduous forests, which are the haunt of the side-striped jackal.
Food
A very opportunistic and versatile omnivore, does not follow preference patterns but rather adapts its diet to the available food sources which require least effort. Contrary to what an occasional observer might believe, the jackal is mostly a killer and not a carrion eater. Its usual kills include tiny bites of invertebrates such as scarabs, grasshoppers, crickets, termites, centipedes, spiders, and scorpions; small mammals like rodents and hares; eggs and ground-nesting birds like Guinea fowls and francolins; or reptiles such as lizards and snakes. Yet, it does not either refuse some vegetal food like fruits and berries. Family parties sometimes hunt as a team, a technique that allows them to stalk larger prey, like small antelopes and gazelle fawns: duikers, dik-diks, Thomson's gazelles, or even topi calves. They can also attack small cattle, but it is infrequent in Kenya.
Jackals also feed on carrion. They are promptly attracted by prey of larger carnivores, especially lions. While the big cats eat, jackals remain at a distance together with vultures and hyenas, waiting for the chance to snatch some piece of meat. When antelopes are in the calving season, jackals prowl amidst the herds to eat the foetal sacs.
If the prey is big, the jackal may grab the carcass with its jaws to carry it to the den, but whenever possible it will use a different system to avoid losing the prey to hyenas: swallowing food and carrying it inside the stomach to the den, where it will regurgitate for feeding the pups. It usually buries the excess food someplace inside its territory, storing it for consumption within the next 24 hours. Quite often, these small loots are unearthed by hyenas.
Behaviour
Mostly nocturnal, but can be frequently seen at dawn and dusk. It is said to be very cunning and clever. Though it is sometimes solitary, it is most commonly found in pairs that last for life. It is territorial; each pair dominates a permanent territory, the size of which may vary according to the population density, which is a direct consequence of food availability. The two pair members defend the territory and mark it out with urine, dung and their physical presence.
In addition to territorial defense, cooperation between both pair members is expressed in caring for the pups and, most of all, in hunting. Team stalking allows them to successfully undertake the killing of large prey, like gazelle fawns. While one of them attracts the mother's attention, the other one grabs the calf by biting its neck. Male and female always share the food. If one pair member dies or disappears, the territory will be unavoidably invaded by another pair, which will throw the survivor out and kill the pups.
The jackal lives in dens excavated in the ground. They are usually old termite mounds or holes burrowed by other species. However, occasionally it is the female jackal that perforates the den in soft earth, a 1-2 m tunnel with a single entrance. The family switches place periodically within their territory. When the pups are small, the female moves them every other week.
It is a noisy animal, capable of vocalizing a complex repertoire of calls used mainly for territorial marking and for strengthening family bonds. For the latter purpose, the pair and the pups gather in a characteristic howling chorus. The most usual call is a sharp yell followed by short yaps. Another frequent voice is a plaintive howl, used when they locate cheetah or a lion pride with their fresh kill. The jackal only replies to calls of its own family members. Grooming plays an essential role in family bonding.
More numerous parties are frequently seen. This situation corresponds to the so-called "helpers", youngs of a previous litter that remain with their parents when these give birth to new offspring. This occurs quite often and depending on circumstances: if there is only one survivor from the previous litter, nearly always it will act as a helper for the next offspring. These older siblings take care of the pups while parents go out for food, or otherwise they cooperate in foraging. This helper function is very beneficial for the species. On the one hand, the survival rate of pups is much higher in families with helpers, since youngs find a better protection. In addition, the fact that parents can go out to hunt as a team increases the possibilities of killing larger prey. On the other hand, when helpers protect their younger siblings, they are actually caring for the survival of their own genes, and at the same time they are learning the basic skills of parenting.
As pups grow up, they become less sociable and more aggressive. They start then to keep at a distance, establishing dominance relationships between siblings and between parents and offspring of the same sex. This may finally determine who stays and who leaves the parental den: dominants are more independent and show a trend towards leaving, but in case environmental conditions are unfavourable, they will force their lower rank siblings to withdraw.
The jackal's main predator is the leopard. Pups are also threatened by great eagles and python snakes. Their longevity is 8-10 years.
Reproduction
The jackal procreates during the dry season, from July to October. After a 2-month gestation, the female gives birth to 3-4 pups, maximum 6. Pups are delivered inside the den, where they will remain until 2-3 weeks later. During this period, the mother stays with them for most of the time, while the male and helpers go out for food that they will regurgitate when back in the den. At 3 months, pups acquire the adult coloration and break their dependence of the den, sleeping outside under cover. At 6 months they have learned the basic hunting techniques, though they still obtain most of their food from their parents and older siblings. At 8 months they are old enough to leave the family and to establish a territory of their own.
Related species
Golden or common jackal (Canis aureus, bweha wa mbugua): uniform coat, dark yellow or rufous grey. Back slightly darker, that fuses with the flank's colour. Tail rufous with a dark tip. Ears rufous. Height at shoulder: 43-46 cm. In Kenya it has been recorded locally in Laikipia, Naivasha, Loita Plains, Sotik and Mount Suswa. Inhabits mainly open plains. Nocturnal and occasionally diurnal. Kills large prey by biting flanks and belly, in a similar way to hunting dogs.
Side-striped jackal (Canis adustus, bweha miraba): uniform coat tawny grey, except for a diffuse pale stripe in flanks. Ears dark brown. The only Kenyan jackal with tail of tip white. Height at shoulder: 46 cm. Nocturnal, possibly more than the other two species, but occasionally recorded by day. In Kenya it is much less common than the black-backed. Inhabits plains and open woodlands, even mountain.
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Wildlife