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African wild dog

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African Wild Dog[1]
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Carnivora
Family:
Canidae
Subfamily:
Caninae
Genus:
Lycaon

Brookes, 1827
Species:
L. pictus
Binomial name
Lycaon pictus
(Temminck, 1820)
African Wild Dog range

The African Wild Dog (Lycaon pictus) is a carnivorous mammal of the Canidae family, found only in Africa, especially in scrub savanna and other lightly wooded areas. It is also called the African hunting dog, the Cape hunting dog, the spotted dog, or the painted wolf in English, Wildehond in Afrikaans, and Mbwa mwilu in Swahili. It is the only species in the genus Lycaon.

Anatomy and reproduction

The African Wild Dog has a pelage with an irregular pattern of black, yellow, and white, distinctive for each individual. The scientific name "Lycaon pictus" is derived from the Greek for "wolf" and the Latin for "painted". It is the only canid species to lack Dewclaws on the forelimbs.

Adults typically weigh 17-36 kilograms (37-79 pounds).[3] A tall, lean animal, it stands about 30 inches (75 cm) at the shoulder, with a head and body length averaging about 40 inches (100 cm) and a tail of 12 to 18 inches (30-45 cm). Animals in southern Africa are generally larger than those in eastern or western Africa.

There is little sexual dimorphism, though judging by skeletal dimensions, males are usually 3-7% larger. It has a dental formula of

Dentition
3.1.4.2
3.1.4.3

for a total of 42 teeth. The premolars are relatively large compared to other canids, allowing it to consume a large quantity of bone, much like hyenas.[4] The heel of the lower carnassial M1 is

d with a single cusp, which enhances the shearing capacity of teeth and thus the speed at which prey can be consumed. This feature is called trenchant heel and is shared with two other canids: the Asian Dhole and the South American Bush Dog.

A study established that the African Wild Dog had a Bite Force Quotient of 142, the highest of any extant mammal of the order Carnivora.[5] The BFQ is essentially the strength of bite as measured against the animal's mass.

The African Wild Dog reproduces at any time of year, although mating peaks between March and June during the second half of the rainy season. Litters can contain 2-19 pups, though 10 is the most usual number.[6]The time between births is usually 12-14 months, though it can also be as short as 6 months if all of the previous young die. The typical gestation period is approximately 70 days.[3] Pups are usually born in an abandoned den dug by other animals such as those of the Aardvark. Weaning takes place at about 10 weeks. After 3 months, the den is abandoned and the pups begin to run with the pack. At the age of 8-11 months they can kill small prey, but they are not proficient until about 12-14 months, at which time they can fend for themselves. Pups reach sexual maturity at the age of 12-18 months.

Females will disperse from their birth pack at 14-30 months of age and join other packs that lack sexually mature females. Males typically do not leave the pack they were born to.[7] This is the opposite situation to that in most other social mammals, where a group of related females forms the core of the pack or similar group. In the African Wild Dog, the females compete for access to males that will help to rear their offspring. In a typical pack, males outnumber females by a factor of two to one, and only the dominant female is usually able to rear pups. This unusual situation may have evolved to ensure that packs do not over-extend themselves by attempting to rear too many litters at the same time.[8] The species is also unusual in that other members of the pack including males may be left to guard the pups whilst the mother joins the hunting group; the requirement to leave adults behind to guard the pups may decrease hunting efficiency in smaller packs.[9]

A captive breeding and translocation program at Mkomazi Game Reserve, the first of its kind in East Africa, was founded in 1995 to provide dogs for a multinational effort to stabilize their numbers and to reintroduce the species to its traditional homeland. The dogs are allocated to four breeding compounds to maximize genetic diversity. An extensive veterinary program has been set up to improve their immunity to disease.

Social Structure

African Wild Dogs have an unusual way of deciding dominance. In packs, there are separate male and female hierarchies that will split up if either of the alphas die. In the female group, the oldest will have alpha status over the others, or if the mother of the others will retain her alpha status over her daughters. For the males, in contrast the youngest male or the father of the other males will be dominant. When two such loner separate-gender groups meet, if unrelated they can form a pack together. Dominance is established without blood-shed, as most dogs within a group tend to be related to one another in some way, and even when not this can occur.

They have a submission based hierarchy, instead of a dominance based one. Submission and nonaggression is emphasised heavily, even over food they will beg energetically instead of fight. This is likely because of their manner of raising huge litters of dependant pups, so if one individual is injured the entire pack would not be able to provide as much.[10]

Unrelated African Wild Dogs sometimes join up in packs, but this is usually temporary. Occasionally, instead unrelated cape dogs will attempt hostile takeovers of packs.[11]

Hunting & Diet

Dogs with a carcass

The African Wild Dog hunts in packs. Like most members of the dog family, it is a cursorial hunter, meaning that it pursues its prey in a long, open chase. Nearly 80% of all hunts end in a kill. Members of a pack vocalize to help coordinate their movements. Its voice is characterized by an unusual chirping or squeaking sound, similar to a bird.

After a successful hunt, hunters regurgitate meat for those that remained at the den during the hunt, such as the dominant female and the pups. They will also feed other pack members, such as the sick, injured, or very old that cannot keep up.

The African Wild Dog's main prey varies among populations but always centers around medium-sized ungulates, such as the Impala. While the vast majority of its diet is made up of mammal prey, it sometimes hunts large birds, especially Ostriches.[8]

A few packs will also include large animals in their prey, such as wildebeests and zebras. Hunting larger prey requires a closely coordinated attack, beginning with a rapid charge to stampede the herd. One African Wild Dog then grabs the victim's tail, while another attacks the upper lip, and the remainder disembowel the animal while it is immobilised. This behaviour is also used on other large dangerous prey, such as the warthog, the African Buffalo, giraffe calves, and large antelope—even the one-ton Giant Eland.The dogs often eat their prey while it is still alive. This disemboweling was a reason to regard the African Wild Dog as repulsive, but recent studies have shown that prey of the African Wild Dog die quicker than prey of the lion and the leopard, which kill their prey by grabbing the throat and suffocating the animal.

Remarkably, this large-animal hunting tactic appears to be a learned behavior, passed on from generation to generation within specific hunting packs, rather than an instinctive behaviour found commonly within the species. Some studies have also shown that other information, such as the location of watering holes, may be passed on in a similar fashion.

Distribution and threats

The home range of packs varies enormously, depending on the size of the pack and the nature of the terrain. Their preferred habitat is deciduous forests because of large prey herd size, lack of competition from other carnivores, and better sites for denning.[12] In the Serengeti, the average range has been estimated at 1,500 square kilometres (580 square miles), although individual ranges overlap extensively.[8]

There were once about 500,000 African Wild Dogs in 39 countries, and packs of 100 or more were not uncommon. Now there are only about 3,000-5,500 in fewer than 25 countries.[2] They are primarily found in eastern and southern Africa, mostly in the two remaining large populations associated with the Selous Game Reserve in Tanzania and the population centered in northern Botswana and eastern Namibia. Smaller but apparently secure populations of several hundred individuals are found in Zimbabwe, South Africa (Kruger National Park), and in the Ruaha/Rungwa/Kisigo complex of Tanzania. Isolated populations persist in Zambia, Kenya, and Mozambique.

The African Wild Dog is endangered by habitat loss and hunting. It uses very large territories (and so can persist only in large wildlife protected areas), and it is strongly affected by competition with larger carnivores that rely on the same prey base, particularly the lion and the Spotted Hyena. Lions often will kill as many wild dogs as they can but do not eat them. It is also killed by livestock herders and game hunters, though it is typically no more (perhaps less) persecuted than other carnivores that pose more threat to livestock. Most of Africa's national parks are too small for a pack of wild dogs, so the packs expand to the unprotected areas, which tend to be ranch or farm land. Ranchers and farmers protect their domestic animals by killing the wild dogs. Like other carnivores, the African Wild Dog is sometimes affected by outbreaks of viral diseases such as rabies, distemper, and parvovirus. Although these diseases are not more pathogenic or virulent for wild dogs, the small size of most wild dog populations makes them vulnerable to local extinction due to diseases or other problems.[2]

The Painted Dog Conservation (PDC) effort, based in Hwange National Park, western Zimbabwe, works with local communities to create new strategies for conserving the wild dog and its habitat.

Name controversy

A controversy began in the late 1990s when conservationists working to protect lycaon pictus said that their most common name, "African Wild Dog", was a source of confusion and prejudice. Conservationist Greg Rasmussen wrote in 1998:

"The name 'wild dog' developed during an era of persecution of all predators when the name applied to feral dogs, hyenas, jackals and the cape hunting dogs (Pringle, 1980). 'Painted' aside from being a direct translation of the specific epithet, accurately describes the unique varicoloured markings of each individual. Apart from being misleading, continued use of the name 'wild dog' does little more than further fuel negative attitude and prejudice which is detrimental to conservation efforts."[13]

Rasmussen is one of the founders of the Painted Hunting Dog Research Project. He advocates using the name "painted hunting dog".[14]

Subspecies

There are five recognized subspecies of this canid:[1]

  • Lycaon pictus pictus
  • Lycaon pictus lupinus
  • Lycaon pictus manguensis
  • Lycaon pictus sharicus
  • Lycaon pictus somalicus


Wild Dog research

Founded as the Botswana Wild Dog Research Project in 1989, the Botswana Predator Conservation Trust (BPCT) has expanded to cover all the large carnivore species in Botswana. It is one of the longest running large predator research projects in Africa and one of only a handful of its caliber worldwide. BPCT research on wild dogs has made it abundantly clear that the health and welfare of the entire predator population is a key indication of overall health of the ecosystem. The Government of Botswana, also acknowledging that appropriate and necessary resource management cannot be undertaken in the absence of accurate information about its natural resources, has entrusted BPCT with the task of leading northern Botswana’s conservation and research initiatives on all large carnivores and their associated habitats. The Okavango Delta, where most of BPCT’s research takes place, is a freshwater wetland of global importance. It is the largest Ramsar (International Convention on Wetlands) site on earth and was granted IUCN world heritage status by the World Conservation Union (IUCN).

Under the leadership of Dr JW "Tico" McNutt, a number of international graduate students, Botswana national students, and local staff make up a strong field team that works on African Wild Dogs (Lycaon pictus), leopards (Panthera pardus), cheetahs (Acinonyx jubatus), Spotted Hyenas (Crocuta crocuta), and lions (Panthera leo).


References

  1. ^ a b Wozencraft, W. C. (2005). "Order Carnivora". In Wilson, D. E.; Reeder, D. M. (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. ISBN 978-0-8018-8221-0. OCLC 62265494.
  2. ^ a b c Template:IUCN2008 Database entry includes justification for why this species is endangered
  3. ^ a b "BBC Wildfacts". Retrieved 2008-05-31.
  4. ^ "African wild dog (Lycaon pictus)". Lioncrusher's Domain. Retrieved 2007-06-08.
  5. ^ Wroe, Stephen & McHenry, Colin (2004-10-16). "Bite club: comparative bite force in big biting mammals and the prediction of predatory behaviour in fossil taxa" (PDF). Proc. R. Soc. B. 272: 619. doi:10.1098/rspb.2004.2986. {{cite journal}}: Check date values in: |date= (help)CS1 maint: multiple names: authors list (link)
  6. ^ Animal Info - African Wild Dog
  7. ^ "Animal Info - Wild Dog". Retrieved 2007-06-08.
  8. ^ a b c Malcolm, James (1984). Macdonald, D. (ed.). The Encyclopedia of Mammals. New York: Facts on File. p. 31. ISBN 0-87196-871-1.
  9. ^ Franck Courchamp, Gregory S. A. Rasmussen, and David W. Macdonald (2002). "Small pack size imposes a trade-off between hunting and pup-guarding in the painted hunting dog Lycaon pictus" (PDF). International Society for Behavioral Ecology.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  10. ^ Rebecca Postanowicz (2008). "African Wild Dogs".
  11. ^ Roger Burrows (2002). "Wild Dog Pack Formation".
  12. ^ Creel, Scott & Creel, Nancy (2002). Krebs, J. and Clutton-Brock, T. (ed.). The African Wild Dog: Behavior, Ecology, and Conservation. Princeton: Princeton University Press. p. 59. ISBN 0-69101-654-2.{{cite book}}: CS1 maint: multiple names: authors list (link)
  13. ^ The Name
  14. ^ Curse of the Devil's Dogs

Further reading

Wikispecies has information related to Lycaon.
Wikimedia Commons has media related to Lycaon pictus.
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