The African wild dog (Lycaon pictus), also known as African hunting dog, African painted dog, painted hunting dog, or painted wolf, is a canid native to Sub-Saharan Africa. It is the largest of its family in Africa, and the only extant member of the genus Lycaon, which is distinguished from Canis by its fewer toes and its dentition, which is highly specialised for a hypercarnivorous diet. It is classified as endangered by the IUCN, as it has disappeared from much of its original range. The current population has been estimated at roughly 39 subpopulations containing 6,600 adults, only 1,400 of which are fully grown. The decline of these populations is ongoing, due to habitat fragmentation, human persecution, and disease outbreaks.
The African wild dog is a highly social animal, living in packs with separate dominance hierarchies for males and females. Uniquely among social carnivores, it is the females rather than the males that scatter from the natal pack once sexually mature, and the young are allowed to feed first on carcasses. The species is a specialised diurnal hunter of antelopes, which it catches by chasing them to exhaustion. Like other canids, it regurgitates food for its young, but this action is also extended to adults, to the point of being the bedrock of African wild dog social life. It has few natural predators, though lions are a major source of mortality, and spotted hyenas are frequent kleptoparasites.
Although not as prominent in African folklore or culture as other African carnivores, it has been respected in several hunter-gatherer societies, particularly those of the predynastic Egyptians and the San people.
Video African wild dog
Early accounts and naming
The earliest possible written reference to the species comes from Oppian, who wrote of the thoa, a hybrid between the wolf and leopard, which resembles the former in shape and the latter in colour. Solinus's Collectanea rerum memorabilium from the 3rd century AD describes a multicoloured wolf-like animal with a mane native to Ethiopia.
The species was first described scientifically in 1820 by Coenraad Temminck, after having examined a specimen taken from the coast of Mozambique. He named the animal Hyaena picta, erroneously classifying it as a species of hyena. It was later recognised as a canid by Joshua Brookes in 1827, and renamed Lycaon tricolor. The root word of Lycaon is the Greek ??????? (lykaios), meaning "wolf-like". The specific epithet pictus (Latin for "painted"), which derived from the original picta, was later returned to it, in conformity with the International Rules on Taxonomic Nomenclature.
The English language has several names for Lycaon pictus, including painted lycaon, African wild dog, Cape hunting dog, and painted dog or painted wolf. The latter name is being promoted by some conservationists as a way of rebranding the species, as "wild dog" has several negative connotations that could be detrimental to its image. Nevertheless, the name "African wild dog" is still widely used.
Maps African wild dog
Taxonomy and evolution
The oldest Lycaon pictus fossil dates back 200,000 years ago and was found in HaYonim Cave, Israel. The evolution of the African wild dog is poorly understood due to the scarcity of fossil finds. Some authors consider the extinct Canis subgenus named Xenocyon as ancestral of both genus Lycaon and genus Cuon, which lived throughout Eurasia and Africa from the Early Pleistocene to the early Middle Pleistocene. Others propose that Xenocyon should be reclassified as Lycaon. The species Canis (Xenocyon) falconeri shared the African wild dog's absent first metacarpal (dewclaw), though its dentition was still relatively unspecialised. This connection was rejected by one author because C. (X.) falconeri's missing metacarpal was a poor indication of phylogenetic closeness to the African wild dog, and the dentition was too different to imply ancestry. Another ancestral candidate is the Plio-Pleistocene L. sekowei of South Africa, on the basis of distinct accessory cusps on its premolars and anterior accessory cuspids on its lower premolars. These adaptions are found only in Lycaon among living canids, which shows the same adaptations to a hypercarnivorous diet. L. sekowei had not yet lost the first metacarpal absent in L. pictus, and was more robust than the modern species, having 10% larger teeth.
Paleontologist George G. Simpson placed L. pictus in the subfamily Simocyoninae, along with Cuon alpinus and Speothos venaticus, on the basis of all three species having similarly trenchant carnassials. This grouping was disputed by Juliet Clutton-Brock, who argued that, other than dentition, there were too few similarities between the three species to warrant classifying them in a single subfamily. The species' molecular genetics indicate that it is closely related to genus Canis. Phylogenetic studies place L. pictus and Cuon alpinus into a clade of "wolf-like canids" alongside the extant members of Canis, including C. simensis, C. aureus, C. latrans, C. lupus and the more basal C. adustus and C. mesomelas.
Subspecies
As of 2005, five subspecies are recognised by MSW3:
Nevertheless, although the species is genetically diverse, these subspecific designations are not universally accepted. It was once thought that East African and Southern African L. pictus populations were genetically distinct, based on a small number of samples. More recent studies with a larger number of samples showed that there has been extensive intermixing between East African and Southern African populations in the past. Some unique nuclear and mitochondrial alleles are found in Southern African and north-eastern African populations, with a transition zone encompassing Botswana, Zimbabwe and south-eastern Tanzania between the two. The West African L. pictus population may possess a unique haplotype, thus possibly constituting a truly distinct subspecies.
Physical description
The African wild dog is the bulkiest and most solidly built of African canids. The species stands 60-75 cm (24-30 in) in shoulder height, and weighs 20-25 kg (44-55 lb) in East Africa and up to 30 kg (66 lb) in southern Africa. Females are generally 3-7% smaller than males. Compared to members of the genus Canis, the African wild dog is comparatively lean and tall, with outsized ears and lacking dewclaws. The middle two toepads are usually fused. Its dentition also differs from that of Canis by the degeneration of the last lower molar, the narrowness of the canines, and proportionately large premolars, which are the largest relative to body size of any carnivore other than hyenas. The heel of the lower carnassial M1 is crested with a single blade-like cusp, which enhances the shearing capacity of the teeth and thus the speed at which prey can be consumed. This feature, termed "trenchant heel", is shared with two other canids: the Asian dhole and the South American bush dog. The skull is relatively shorter and broader than that of other canids.
The fur of the African wild dog differs significantly from that of other canids, consisting entirely of stiff bristle-hairs with no underfur. It gradually loses its fur as it ages, with older specimens being almost naked. Colour variation is extreme, and may serve in visual identification, as African wild dogs can recognise each other at distances of 50-100 metres. There is some geographic variation in coat colour, with north-east African specimens tending to be predominantly black with small white and yellow patches, while southern African ones are more brightly coloured, sporting a mix of brown, black and white coats. Much of the species' coat patterning occurs on the trunk and legs. There is little variation in facial markings, with the muzzle being black, gradually shading into brown on the cheeks and forehead. A black line extends up the forehead, turning blackish-brown on the back of the ears. A few specimens sport a brown teardrop shaped mark below the eyes. The back of the head and neck are either brown or yellow. A white patch occasionally occurs behind the forelegs, with some specimens having completely white forelegs, chests and throats. The tail is usually white at the tip, black in the middle and brown at the base. Some specimens lack the white tip entirely, or may have black fur below the white tip. These coat patterns are asymmetrical, with the left side of the body often having different markings from that of the right.
Behaviour
Social and reproductive behaviour
The African wild dog has very strong social bonds, stronger than those of sympatric lions and spotted hyenas; thus, solitary living and hunting are extremely rare in the species. It lives in permanent packs consisting of 2-27 adults and yearling pups. The average pack size in Kruger National Park and the Masai Mara is 4-5 adults, while packs in Moremi and Selous contain an average of 8-9. However, larger packs have been observed, and temporary aggregations of hundreds of individuals may have gathered in response to the seasonal migration of vast springbok herds in Southern Africa. Males and females have separate dominance hierarchies, with the latter usually being led by the oldest female. Males may be led by the oldest male, but these can be supplanted by younger specimens; thus, some packs may contain elderly former male pack leaders. The dominant pair typically monopolises breeding. The species differs from most other social species by the fact that males remain in the natal pack, while females disperse (a pattern also found in primates like gorillas, chimpanzees and red colobuses). Furthermore, males in any given pack tend to outnumber females 3:1. Dispersing females will join other packs and evict some of the resident females related to the other pack members, thus preventing inbreeding and allowing the evicted individuals to find new packs of their own and breed. Males rarely disperse, and when they do, they are invariably rejected by other packs already containing males. Although arguably the most social canid, the species lacks the elaborate facial expressions and body language found in the grey wolf, likely because of the African wild dog's less hierarchical social structure. Furthermore, while elaborate facial expressions are important for wolves in re-establishing bonds after long periods of separation from their family groups, they are not as necessary to African wild dogs, which remain together for much longer periods.
African wild dog populations in East Africa appear to have no fixed breeding season, whereas those in Southern Africa usually breed during the April-July period. During estrus, the female is closely accompanied by a single male, who keeps other members of the same sex at bay. The copulatory tie characteristic of mating in most canids has been reported to be absent or very brief (less than one minute) in L. pictus, possibly an adaptation to the prevalence of larger predators in its environment. The gestation period lasts 69-73 days, with the interval between each pregnancy being 12-14 months on average. The African wild dog produces more pups than any other canid, with litters containing around 6-16 pups, with an average of 10, thus indicating that a single female can produce enough young to form a new pack every year. Because the amount of food necessary to feed more than two litters would be impossible to acquire by the average pack, breeding is strictly limited to the dominant female, which may kill the pups of subordinates. After giving birth, the mother stays close to the pups in the den, while the rest of the pack hunts. She typically drives away pack members approaching the pups until the latter are old enough to eat solid food at 3-4 weeks of age. The pups leave the den at around the age of three weeks, and are suckled outside. The pups are weaned at the age of five weeks, at which point they are fed regurgitated meat by the other pack members. By seven weeks, the pups begin to take on an adult appearance, with noticeable lengthening in the legs, muzzle and ears. Once the pups reach the age of 8-10 weeks, the pack abandons the den, and the young follow the adults during hunts. The youngest pack members are permitted to eat first on kills, a privilege which ends once they become yearlings.
Sneeze communication and "voting"
African wild dog populations in the Okovango delta have been observed "rallying" before they set out to hunt. Not every rally results in a departure, but departure becomes more likely when more individual dogs "sneeze". These sneezes are characterized by a short sharp exhale through the nostrils. When members of dominant mating pairs sneeze first, the group is much more likely to depart. If a dominant dog initiates, approximately 3 sneezes guarantee departure. When less dominant dogs sneeze first, if enough others also sneeze (~10) then the group will go hunting. Researchers assert that wild dogs in Botswana, "use a specific vocalization (the sneeze) along with a variable quorum response mechanism in the decision-making process [to go hunting at a particular moment]".
Inbreeding avoidance
Because L. pictus largely exists in fragmented small populations, its existence is endangered. Inbreeding avoidance via mate selection is characteristic of the species and has important potential consequences for population persistence. Inbreeding is rare within natal packs. Inbreeding is likely avoided because it leads to the expression of recessive deleterious alleles. Computer-population simulations indicate that all populations continuing to avoid incestuous mating will become extinct within 100 years due to the unavailability of unrelated mates. Thus the impact of reduced numbers of suitable unrelated mates will likely have a severe demographic impact on the future viability of small wild dog populations.
Hunting and feeding behaviours
The African wild dog is a specialised pack hunter of common medium-sized antelopes. It and the cheetah are the only primarily diurnal African large predators. L. pictus hunts by approaching prey silently then chasing it in a pursuit clocking at up to 66 kilometres per hour (41 mph) for 10 to 60 minutes. The average chase typically only goes as far as 2 km, during which time the prey animal, if large, is repeatedly bitten on the legs, belly and anus until it stops running, while smaller prey is simply pulled down and torn apart. L. pictus hunting strategies differ according to prey, with wildebeest being rushed at in order to panic the herd and isolate a vulnerable individual, whereas territorial antelope species, which defend themselves by running in wide circles, are captured by cutting off their escape routes. Medium-sized prey is often killed in 2-5 minutes, whereas larger prey like wildebeest may take half an hour to pull down. Male wild dogs usually perform the task of grabbing dangerous prey, such as warthogs, by the nose. Small prey like rodents, hares and birds are hunted singly, with dangerous prey like cane rats and porcupines being killed with a quick and well-placed bite in order to avoid injury. Small prey is eaten entirely, while large animals are stripped of their meat and organs, with the skin, head, and skeleton left intact. The African wild dog is a fast eater, with a pack being able to consume a Thompson's gazelle in 15 minutes. In the wild, the species' consumption rate is of 1.2-5.9 kg per African wild dog a day, with one pack of 17-43 specimens in East Africa having been recorded to kill three animals per day on average. Unlike most social predators, it will regurgitate food for adult as well as young family members. Pups old enough to eat solid food are given first priority at kills, eating even before the dominant pair; subordinate adult dogs help feed and protect the pups. The African wild dog is a highly successful hunter. Hunting success varies with prey type, vegetation cover and pack size, but African hunting dogs tend to be very successful often with greater than 60% of their chases ending in a kill, sometimes up to 90%. This is much higher than lion (27-30%) and hyena (25-30%) success rates tend to be but African Wild dogs commonly lose their successful kills to these two large, African predators.
Ecology
Habitat
The African wild dog is mostly found in savanna and arid zones, generally avoiding forested areas. This preference is likely linked to the animal's hunting habits, which require open areas that do not obstruct vision or impede pursuit. Nevertheless, it will travel through scrub, woodland and montane areas in pursuit of prey. Forest-dwelling populations of African wild dogs have been identified, including one in the Harenna Forest, a wet montane forest up to 2400m in altitude in the Bale Mountains of Ethiopia. There is at least one record of a pack being sighted on the summit of Mount Kilimanjaro. In Zimbabwe, the species has been recorded at altitudes of 1,800 metres. In Ethiopia, this species has been found at great altitudes; several live wild dog packs have been sighted at altitudes of from 1,900 meters to 2,800 meters, and a dead individual was found in June 1995 at 4,050 meters on the Sanetti Plateau.
Diet
In East Africa, its most common prey is Thomson's gazelle, while in Central and Southern Africa it targets impala, reedbuck, kob, lechwe, and springbok. Its diet is not restricted to these animals though, as it will also hunt wildebeest, warthog, oribi, duiker, waterbuck, Grant's gazelle, zebra, bushbuck, ostrich, African buffalo (especially calves), and smaller prey like dik-dik, hares, spring hares and cane rats. Certain packs in the Serengeti specialized in hunting zebras in preference to other prey. One pack was recorded to occasionally prey on bat-eared foxes, rolling on the carcasses before eating them. African wild dogs rarely scavenge, but have on occasion been observed to appropriate carcasses from spotted hyenas, leopards, cheetahs, and lions, as well as animals caught in snares.
Enemies and competitors
Lions dominate African wild dogs, and are a major source of mortality for both adults and pups. Population densities of African wild dogs are low in areas where lions are more abundant. One pack reintroduced into Etosha National Park was destroyed by lions. A population crash in lions in the Ngorongoro Crater during the 1960s resulted in an increase in African wild dog sightings, only for their numbers to decline once the lions recovered. However, there are a few reported cases of old and wounded lions falling prey to African wild dogs. On occasion, packs of wild dogs have been observed defending pack members attacked by single lions, sometimes successfully. One pack in the Okavango in March 2016 was photographed by safari guides waging "an incredible fight" against a lioness that attacked a subadult dog at an impala kill, which forced the lioness to retreat although the subadult dog died. Naturalists John McNutt and Lesley Bogg McNutt, founders of the Botswana Predator Conservation Trust, observed a pack of 4 wild dogs furiously defend an old adult male dog from a male lion that attacked it at a kill; the dog survived and rejoined the pack.
Spotted hyenas are important kleptoparasites, and will follow packs of African wild dogs in order to appropriate their kills. They will typically inspect areas where African wild dogs have rested and eat any food remains they find. When approaching African wild dogs at a kill, solitary hyenas will approach cautiously and attempt to take off with a piece of meat unnoticed, though they may be mobbed in the attempt. When operating in groups, spotted hyenas are more successful in pirating African wild dog kills, though the latter's greater tendency to assist each other puts them at an advantage against spotted hyenas, who rarely work in unison. Cases of African wild dogs scavenging from spotted hyenas are rare. Although African wild dog packs can easily repel solitary hyenas, on the whole, the relationship between the two species is a one-sided benefit for the hyenas, with African wild dog densities being negatively correlated with high hyena populations.
Range
African wild dogs once ranged from the desert and mountainous areas of much of sub-Saharan Africa, being absent in the driest desert regions and lowland forests. The species has been largely exterminated in North and West Africa, and has been greatly reduced in number in Central Africa and northeast Africa. The majority of the species' population now occurs in Southern Africa and southern East Africa.
Status
North Africa
The species is very rare in North Africa, and whatever populations remain may be of high conservation value, as they are likely to be genetically distinct from other L. pictus populations.
West Africa
The species is faring poorly in most of West Africa, with the only potentially viable population occurring in Senegal's Niokolo-Koba National Park. African wild dogs are occasionally sighted in other parts of Senegal, as well as in Guinea and Mali.
Central Africa
The species is doing poorly in Central Africa, being extinct in Gabon, the Democratic Republic of Congo and the Republic of Congo. The only viable populations occur in the Central African Republic, Chad and especially in Cameroon.
East Africa
L. pictus's range in East Africa is patchy, having been eradicated in Uganda and much of Kenya. A small population occupies an area encompassing southern Ethiopia, South Sudan, northern Kenya, and probably northern Uganda. The species may still occur in small numbers in southern Somalia, and is almost certainly extinct in Rwanda, Burundi, and Eritrea. Nevertheless, it remains somewhat numerous in southern Tanzania, particularly in the Selous Game Reserve and Mikumi National Park, both of which are occupied by what could be Africa's largest L. pictus population.
Southern Africa
Southern Africa contains numerous viable L. pictus populations, one of which encompasses northern Botswana, northeastern Namibia and western Zimbabwe. In South Africa, around 400 specimens occur in the country's Kruger National Park. Zambia holds two large populations, one in Kafue National Park, and another in the Luangwa Valley. However, the species is rare in Malawi, and probably extinct in Angola and Mozambique.
In African cultures
Artistic depictions of African wild dogs are prominent on cosmetic palettes and other objects from Egypt's predynastic period, likely symbolising order over chaos, as well as the transition between the wild (represented by the African golden wolf) and the domestic (represented by the dog). Predynastic hunters may have also identified with the African wild dog, as the Hunters Palette shows them wearing the animals' tails on their belts. By the dynastic period, African wild dog illustrations became much less represented, and the animal's symbolic role was largely taken over by the wolf.
According to Enno Littmann, the people of Ethiopia's Tigray Region believed that injuring a wild dog with a spear would result in the animal dipping its tail in its wounds and flicking the blood at its assailant, causing instant death. For this reason, Tigrean shepherds would repel wild dog attacks with pebbles rather than with edged weapons.
The African wild dog also plays a prominent role in the mythology of Southern Africa's San people. In one story, the wild dog is indirectly linked to the origin of death, as the hare is cursed by the moon to be forever hunted by African wild dogs after the hare rebuffs the moon's promise to allow all living things to be reborn after death. Another story has the god Cagn taking revenge on the other gods by sending a group of men transformed into African wild dogs to attack them, though who won the battle is never revealed. The San of Botswana see the African wild dog as the ultimate hunter, and traditionally believe that shamans and medicine men can transform themselves into the wild dog. Some San hunters will smear African wild dog bodily fluids on their feet before a hunt, believing that doing so will give them the animal's boldness and agility. Nevertheless, the species does not figure prominently in San rock art, with the only notable example being a frieze in Mount Erongo showing a pack hunting two antelopes.
See also
- African Wild Dog Conservancy
- Botswana Wild Dog Research Project
- Harnas Wildlife Foundation
- Institute of Zoology
- Painted Dog Conservation
- Wildlife Conservation Network
References
Further reading
- Githiru et al. (2007). African wild dogs (Lycaon pictus) from NE Kenya: Recent records and conservation issues. Zoology Department Research Report. National Museum of Kenya.
- Van Lawick, H. & Goodall, J. (1971). Innocent Killers. Houghton Mifflin Company Boston
- Wozencraft, W. C. (November 2005). D. E. Wilson and D. M. Reeder (eds), Mammal Species of the World (3rd edition ed.) Johns Hopkins University Press. ISBN 0-8018-8221-4. Bucknell.edu
External links
- painteddog.org, Painted Dog Conservation Website
- painteddog.co.uk/, Painted Dog Conservation United Kingdom Website
- African Wild Dog Conservancy
- African Wild Dog Watch
- Wild Dog conservation in Zimbabwe
- Namibia Nature Foundation Wild Dog Project: Conservation of African wild dogs in Namibia
- African wild dogs: Wildlife summary at African Wildlife Foundation
- The Zambian Carnivore Programme
- Save the African wild dog
- Wildentrust.org
- Painted Dog Conservation (conservation organization)
- Photos, videos and information from ARKive
- ibream wild dog project
- African Wild Dog - Painted Dog Conservation at WCN Wildlife Conservation Network
Source of article : Wikipedia
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