Black-backed jackal

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Black-backed jackal
Temporal range: Pliocene - Recent
2012-bb-jackal-1.jpg
Cape jackal (C. m. mesomelas) feeding on a springbok carcass, Etosha National Park, Namibia.
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Canidae
Genus: Canis
Species: C. mesomelas
Binomial name
Canis mesomelas
(Schreber, 1775)
Subspecies

2 ssp., see text

Black-backed Jackal area.png
Black-backed jackal range

The black-backed jackal (Canis mesomelas) is a canid native to two areas of the Africa, separated by roughly 900 km. One region includes the southernmost tip of the continent, including South Africa, Namibia, Botswana, and Zimbabwe. The other area is along the eastern coastline, including Kenya, Somalia, Djibouti and Ethiopia. It is listed by the IUCN as least concern, due to its widespread range and adaptability, although it is still persecuted as a livestock predator and rabies vector.[1]

Compared to other members of the genus Canis, the black-backed jackal is a very ancient species, and has changed little since the Pleistocene,[2] being the most basal canine alongside the closely related side-striped jackal.[3] It is a fox-like canid[4] with a reddish coat and a black saddle that extends from the shoulders to the base of the tail.[5] It is a monogamous animal, whose young may remain with the family to help raise new generations of pups.[6] The black-backed jackal is not a fussy eater, and will feed on small to medium sized animals, as well as plant matter and human refuse.[7]

Etymology[edit]

In English, the species is known by several different names, including saddle-backed, grey, silver, red, and golden jackal (not to be confused with Canis aureus). The Latin mesomelas is a compound consisting of meso (middle) and melas (black).[5]

Local and indigenous names[edit]

Taxonomy and evolution[edit]

Comparison between the skulls of the basal black-backed jackal and advanced grey wolf.

The earliest fossil carnivores that can be linked with some certainty to canids are the Eocene Miacids, which lived some 38 to 56 million years ago. The Miacids later diverged into caniforms and feliforms, with the former line leading to such genera as the coyote-sized Mesocyon of the Oligocene (38 to 24 million years ago), the fox-like Leptocyon and the wolf-like Tomarctus which inhabited North America some 10 million years ago.[8] The black-backed jackal has occupied eastern and southern Africa for at least 2-3 million years, as shown by fossil deposits in Kenya, Tanzania and South Africa. Specimens from fossil sites in Transvaal are almost identical to their modern counterparts, but have slightly different nasal bones.[5] As no fossils have been found north of Ethiopia, it is likely that the species has always been sub-Saharan in distribution.[7] The black-backed jackal is relatively unspecialised, and can thrive in a wide variety of habitats, including deserts, as its kidneys are well adapted for water deprivation. It is however more adapted to a carnivorous diet than the other jackals, as shown by its well-developed carnassial shear and the longer cutting blade of the premolars.[4]

Juliet Clutton-Brock classed the black-backed jackal as being closely related to the side-striped jackal, based on cranial and dental characters.[9] Studies on allozyme divergence within the Canidae indicate that the black-backed jackal has a great degree of genetic distance between it and other members of the genus Canis.[10] Further studies on the species' mitochondrial DNA show a large sequence divergence between black-backed jackals and other sympatric "jackal" species, having diverged 2.3–4.5 million years ago.[11] Its genome indicates that, along with the side-striped jackal, it forms a basal clade behind the African wild dog and dhole, both of which are more closely related to the remaining members of the genus Canis than the two jackal species are, despite being placed in the genera Lycaon and Cuon respectively.[3](Fig. 10)





Side-striped jackal



Black-backed jackal








Golden jackal





Dog



Grey wolf




Coyote





Ethiopian wolf




Dhole





African wild dog






Subspecies[edit]

As of 2005,[12] two subspecies are recognised by MSW3. These subspecies are geographically separated by a gap which extends northwards from Zambia to Tanzania:[5]

Physical description[edit]

The black-backed jackal is a fox-like canid[4] with a slender body, long legs and large ears.[5] It is similar to the closely related side-striped jackal and unrelated golden jackal, though its skull and dentition are more robust and the incicors much sharper.[4] It weighs 6–13 kg (13–29 lb),[4] stands 38–48 cm (15–19 in) at the shoulder and measures 67.3–81.2 cm (26.5–32.0 in) in body length.[5]

The base colour is reddish brown to tan, which is particularly pronounced on the flanks and legs. A black saddle intermixed with silvery hair extends from the shoulders to the base of the tail.[5] A long black stripe extending along the flanks separates the saddle from the rest of the body, and can be used to differentiate individuals.[4] The tail is bushy and tipped with black. The lips, throat, chest and inner surface of the limbs are white.[5] The winter coat is a much deeper reddish brown.[4] Albino specimens occasionally occur.[4] The hair of the face measures 10–15 mm in length, and lengthens to 30–40 mm on the rump. The guard hairs of the back are 60 mm on the shoulder, decreasing to 40 mm at the base of the tail. The hairs of the tail are the longest, measuring 70 mm in length.[7]

Behaviour[edit]

East African jackal (C. m. schmidti) pups, Tanzania.

Social and territorial behaviours[edit]

The black-backed jackal is a monogamous and territorial animal, whose social organisation greatly resembles that of the golden jackal. However, unlike the latter species, the assistance of elder offspring in helping raise the pups of their parents has a greater bearing on pup survival rates.[6] The basic social unit is a monogamous mated pair which defends its territory through laying faeces and urine on range boundaries. Scent marking is usually done in tandem, and the pair will aggressively expel intruders. Such encounters are normally prevented, as the pair will vocalise to advertise its presence in a given area. It is a highly vocal species, particularly in Southern Africa.[4] Sounds made by the species include yelling, yelping, woofing, whining, growling and cackling.[6] It communicates with group members and advertises its presence via a high-pitched whining howl, and expresses alarm through an explosive cry followed by shorter high-pitched yelps. This sound is particularly frantic when mobbing a leopard. In areas where the black-backed jackal is sympatric with the golden jackal, the species does not howl, instead relying more on yelps. In contrast, black-backed jackals in Southern Africa howl much like golden jackals.[4] When trapped, it cackles like a fox.[6]

Reproduction and development[edit]

The mating season takes place from late May to August, with a gestation period of 60 days. Pups are born from July to October. Summer births are thought to be timed to coincide with population peaks of vlei rats and four-striped grass mice, while winter births are timed for ungulate calving seasons.[7] Litters consist of 1-9 pups, which are born blind. For the first three weeks of their lives, the pups are kept under constant surveillance by their mother, while the father and elder offspring provide food.[6] The pups open their eyes after 8-10 days and emerge from the den at the age of three weeks. They are weaned at 8-9 weeks, and can hunt by themselves at the age of six months. Sexual maturity is attained at 11 months, though few black-backed jackals reproduce in their first year.[4] Unlike golden jackals, which have comparatively amicable intrapack relationships, black-backed jackal pups become increasingly quarrelsome as they age, and establish more rigid dominance hierarchies. Dominant pups will appropriate food, and become independent at an earlier age.[6] The grown pups may disperse at one year of age, though some will remain in their natal territories to assist their parents in raising the next generation of pups. The average lifespan in the wild is seven years, though captive specimens can live twice as long.[4]

Ecology[edit]

Habitat[edit]

The species generally shows a preference for open areas with little dense vegetation, though it occupies a wide range of habitats, from arid coastal deserts to areas with more than 2000 mm of rainfall. It also occurs in farmlands, savannas, open savanna mosaics and alpine areas.[4]

Diet[edit]

Cape jackal (C. m. mesomelas) feeding on a brown fur seal pup, Namibia.

Black-backed jackals are omnivores, which feed on invertebrates, such as beetles, grasshoppers, crickets, termites, millipedes, spiders and scorpions. They will also feed on mammals, such as rodents, hares and young antelopes up to the size of topi calves. They will also feed on carrion, lizards, and snakes.[5] A pair of black-backed jackals in the Kalahari desert was observed to kill and devour a kori bustard and, on a separate occasion, a black mamba via prolonged harassment of the snake and crushing of the snake's head.[13] Black-backed jackals will occasionally feed on fruits and berries.[6] In coastal areas, they will feed on beached marine mammals, seals, fish and mussels.[7] A single jackal is capable of killing a healthy adult impala.[14] Adult dik dik and Thomson's gazelles seem to be the upper limit of their killing capacity, though they will target larger species if they are sick, with one pair having been observed to harass a crippled bull rhinoceros. They typically kill tall prey by biting at the legs and loins, and will frequently go for the throat.[4] In Serengeti woodlands, they feed heavily on African Grass Rats. In East Africa, during the dry season, they hunt the young of gazelles, impalas, topi, tsessebe and warthogs.[6] In South Africa, black-backed jackals frequently prey on antelopes (primarily impala and springbok and occasionally duiker, reedbuck and steenbok), carrion, hares, hoofed livestock, insects, and rodents. They will also prey on small carnivores, such as mongooses, polecats and wildcats. On the coastline of the Namib Desert, jackals feed primarily feed on marine birds (mainly Cape and white-breasted cormorants and jackass penguins), marine mammals (including Cape fur seals), fish, and insects.[5] Like most canids, the black-backed jackal caches surplus food.[6]

Enemies and competitors[edit]

In areas where the black-backed jackal is sympatric with the larger side-striped jackal, the former species aggressively drives out the latter from grassland habitats into woodlands. This is unique among carnivores, as it is more common for larger species to displace smaller ones.[15] Black-backed jackal pups are vulnerable to golden jackals,[7] ratels, and spotted and brown hyenas. Adults have few natural predators, save for leopards, caracals, African wild dogs, and martial eagles.[4]

Diseases and parasites[edit]

Black-backed jackals can carry diseases such as rabies, canine parvovirus, canine distemper, canine adenovirus, Ehrlichia canis and African horse sickness. Jackals in Etosha National Park may carry anthrax. Black-backed jackals are major rabies vectors, and have been associated with epidemics, which appear to cycle every four to eight years. Jackals in Zimbabwe are able to maintain rabies independently of other species. Although oral vaccinations are effective in jackals, the long-term control of rabies continues to be a problem in areas where stray dogs are not given the same immunisation.[5]

Jackals may also carry trematodes such as Athesmia, cestodes such as Dipylidium caninum, Echinococcus granulosus, Joyeuxialla echinorhyncoides, J. pasqualei, Mesocestoides lineatus, Taenia erythraea, T. hydatigena, T. jackhalsi, T. multiceps, T. pungutchui, and T. serialis. Nematodes carried by black-backed jackals include Ancylostoma braziliense, A. caninum, A. martinaglia, A. somaliense, A. tubaeforme, and Physaloptera praeputialis, and protozoans such as Babesia canis, Ehrlichia canis, Hepatozoon canis, Rickettsia canis, Sarcocytis spp., Toxoplasma gondii, and Trypanosoma congolense. Mites may cause sarcoptic mange. Tick species include Amblyomma hebraeum, A. marmoreum, A. nymphs, A. variegatum, Boophilus decoloratus, Haemaphysalis leachii, H. silacea, H. spinulosa, Hyelomma spp., Ixodes pilosus, I. rubicundus, Rhipicephalus appendiculatus, R. evertsi, R. sanguineus, and R. simus. Flea species include Ctenocephalides cornatus, Echidnophaga gallinacea, and Synosternus caffer.[5]

Relationships with humans[edit]

In folklore[edit]

Black-backed jackals feature prominently in the folklore of the Khoikhoi, where it is often paired with the lion, whom it frequently outsmarts or betrays with its superior intelligence. One story explains that the black-backed jackal gained its dark saddle when it offered to carry the sun on its back.[16] An alternative account comes from the ǃKung people, whose folklore tells that the jackal received the burn on its back as a punishment for its scavenging habits.[17]

Livestock predation[edit]

Black-backed jackals will occasionally hunt domestic animals, including dogs, cats, pigs, goats, sheep, and poultry, with sheep tending to predominate. They rarely target cattle, though cows giving birth may be attacked. Jackals can be a serious problem for sheep farmers, particularly during the lambing season. Sheep losses to black-backed jackals in a 440 km study area in KwaZulu-Natal consisted of 0.05% of the sheep population. Of 395 sheep killed in a sheep farming area in KwaZulu-Natal, 13% were killed by jackals. Jackals usually kill sheep via a throat bite, and will begin feeding by opening the flank and consuming the flesh and skin of the flank, heart, liver, some ribs, haunch of hind leg, and sometimes the stomach and its contents. In older lambs, the main portions eaten are usually heart and liver. Usually only one lamb per night is killed in any one place, but sometimes two and occasionally three may be killed.[5] The oral history of the Khoikhoi indicates they have been a nuisance to pastoralists long before European settlement. South Africa has been using fencing systems to protect sheep from jackals since the 1890s, though such measures have mixed success, as the best fencing is expensive, and jackals can easily infiltrate cheap wire fences.[18]

Hunting[edit]

Main article: Jackal coursing
Black-backed jackal pelt

Due to livestock losses to jackals, many hunting clubs were opened in South Africa in the 1850s. Black-backed jackals have never been successfully eradicated in hunting areas, despite strenuous attempts to do so with dogs, poison and gas.[7] Black-backed jackal coursing was first introduced to the Cape Colony in the 1820s by Lord Charles Somerset who, as well as an avid fox hunter, sought a more effective method of managing jackal populations, as shooting proved ineffective.[18] Coursing jackals also became a popular pastime in the Boer Republics.[19] In the western Cape in the early 1900s, dogs bred by crossing foxhounds, lurchers and borzoi were used.[18]

Spring traps with metal jaws were also effective, though poisoning by strychnine became more common by the late 19th century. Strychnine poisoning was initially problematic, as the solution had a bitter taste, and could only work if swallowed. Consequently, many jackals learned to regurgitate poisoned baits, thus inciting wildlife managers to use the less detectable crystal strychnine rather than liquid. The poison was usually placed within sheep carcasses or in balls of fat, with great care being taken to avoid leaving any human scent on them. Black-backed jackals were not a popular quarry in the 19th century, and are rarely mentioned in hunter's literature. By the turn of the century, jackals became increasingly popular quarry as they encroached upon human habitations after sheep farming and veld burning diminished their natural food sources. Although poisoning had been effective in the late 19th century, its success rate in eliminating jackals waned in the 20th century, as jackals seemed to be learning to distinguish poisoned foods.[18]

The Tswana people often made hats and cloaks out of black-backed jackal skins. Between 1914 and 1917, 282,134 jackal pelts (nearly 50,000 a year) were produced in South Africa. Demand for pelts grew during the First World War, and were primarily sold in Cape Town and Port Elizabeth. Jackals in their winter fur were in great demand, though animals killed by poison were less valued, as their fur would shed.[18]

References[edit]

  1. ^ a b Loveridge & Nel (2008). Canis mesomelas. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 11 May 2008. Database entry includes justification for why this species is of least concern
  2. ^ Kingdon, J. (1977), East African Mammals: An Atlas of Evolution in Africa, Volume 3, Part A: Carnivores, University of Chicago Press, p. 31
  3. ^ a b Lindblad-Toh, K.; Wade, CM; Mikkelsen, TS; Karlsson, EK; Jaffe, DB; Kamal, M; Clamp, M; Chang, JL et al. (2005). "Genome sequence, comparative analysis and haplotype structure of the domestic dog". Nature 438 (7069): 803–819. doi:10.1038/nature04338. PMID 16341006. 
  4. ^ a b c d e f g h i j k l m n o Kingdon, J. & Hoffman, M. (2013), Mammals of Africa Volume V, Bloomsbury : London, pp. 39-45, ISBN 1408189968
  5. ^ a b c d e f g h i j k l m n Walton, L. R. & Joly, D. O. (2003), Canis mesomelas, Mammalian Species, No. 715, pp. 1-9
  6. ^ a b c d e f g h i Estes, R. (1992). The behavior guide to African mammals: including hoofed mammals, carnivores, primates. University of California Press. pp. 404-408. ISBN 0-520-08085-8.
  7. ^ a b c d e f g h Loveridge, A.J. & Nel, J.A.J. 2004. Black-backed jackal Canis mesomelas. In Sillero-Zubiri, C., Hoffman, M. & MacDonald, D. W., ed., Canids: Foxes, Wolves, Jackals and Dogs - 2004 Status Survey and Conservation Action Plan, pp. 161-166. IUCN/SSC Canid Specialist Group, ISBN 2-8317-0786-2
  8. ^ Brewer, Douglas J.; Terence, Sir Clark; Phillips, Adrian (March 2002). DOGS IN ANTIQUITY Anubis to Cerberus: The Origins of the Domestic Dog. Aris & Phillips. ISBN 978-0-85668-704-4. 
  9. ^ Clutton-Brock, J., Corbet, G.G., and Hills, M. (1976), "A review of the family Canidae, with a classification by numerical methods", Bull. Brit. Mus. Nat. Hist. 29, 148.
  10. ^ Wayne, R. K. & O'Brien, S. J. (1987), Allozyme divergence within the Canidae, Systematic Zoology 36: 339–355
  11. ^ Wayne, R. K. et al. (1989), Genetic and morphologic divergence among sympatric canids, Journal of Heredity 80:447–454
  12. ^ Wozencraft, W. C. (2005). "Order Carnivora". In Wilson, D. E.; Reeder, D. M. Mammal Species of the World (3rd ed.). Johns Hopkins University Press. pp. 532–628. ISBN 978-0-8018-8221-0. OCLC 62265494. 
  13. ^ Owens, M. & Owens, D. (1984), Cry of the Kalahari, Boston: Houghton Mifflin, pp. 54-5, 62-3
  14. ^ Kamler, J. F. et al., Single black-backed jackal (Canis mesomelas) kills adult impala (Aepyceros melampus), African Journal of Ecology, 29 Sep 2009
  15. ^ Loveridge, A.J. & Macdonald, D.W. (2002) Habitat ecology of two sympatric species of jackals in Zimbabwe. Journal of Mammalogy, 83: 599-607.
  16. ^ Bleek, W. H. I. (1864), Reynard the fox in South Africa: or, Hottentot fables and tales, Trübner and co., pp. 67-
  17. ^ Biesele, M. (1972), The black-backed jackal and the brown hyena : a !Kung Bushman folktale, Botswana notes and records 4:133-134.
  18. ^ a b c d e Beinart, W. (2003), The rise of conservation in South Africa: settlers, livestock, and the environment 1770-1950, Oxford University Press, ISBN 0-19-926151-2
  19. ^ Cornish, C. J. et al. (1902), (The living animals of the world; a popular natural history with one thousand illustrations Volume 1: Mammals, New York, Dodd, Mead and Company, pp. 92

External links[edit]