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African wild dog |
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He is a wild animal |
Origin |
Africa | |
Translation |
Francis Vandersteen |
| The possession of this animal is not authorized |
| The scientific name "Lycaon pictus" is derived from the Greek for "wolf" and the Latin for "painted". It is the only canid species without dewclaws on its forelegs. It is the largest African canid and the second-largest wild canid in the world, behind the gray wolf. Adults generally weigh between 18 and 36 kilograms. A tall, lean animal, it measures around 75 cm at the shoulder, with a head and body length of 75-141 cm plus a tail of 30-45 cm. Southern African animals are generally larger than those from East or West Africa. There is little sexual dimorphism, but judging by skeletal dimensions, males are generally 3-7% larger. It has a dental formula of 3.1.4.2 - 3.1.4.3 for a total of 42 teeth. The premolars are relatively large compared with those of other canids, enabling it to consume a large amount of bone, just like the hyena. The heel of the carnassial lower M1 is notched with a single cusp, which improves the shearing capacity of the teeth and therefore the speed at which prey can be consumed. This characteristic is called trenchant heel and is shared with two other canids: the Asian dhole and the South American bush dog. The African wild dog can breed at any time of year, although peaks mate between March and June during the second half of the rainy season. The copulatory link characteristic of mating in most canids has been reported to be absent or very short (less than a minute) in the African wild dog, perhaps an adaptation to the prevalence of large predators in its environment. Adult females have 12 to 14 teats. Litters may contain 2 to 19 pups, although 10 is the most common. The time between births is usually 12 to 14 months, but can be as short as six months if all the previous young die. The typical gestation period is between 60 and 80 days. Puppies are usually born in dens dug and abandoned by other animals, such as aardvarks. Weaning takes place at around 10-11 weeks, although all-male packs without adult females have been successfully observed raising pups as early as 5 weeks of age. After three months, the pups leave the den and start running with the pack. At eight to 11 months of age, they can kill a small prey, but depend on the pack to kill most of their food. They do not become competent hunters until they are 12-14 months old. Wild dogs reach sexual maturity at 12-18 months. Females separate from their birth pack at 14-30 months and join other packs that lack sexually mature females. Males generally do not leave the pack in which they were born. This is unusual among social mammals, among which the basic pack tends to be made up of related females. Among African wild dogs, females compete for access to the males who will help raise their offspring. In a typical pack, males outnumber females two to one, and only the dominant female can usually raise pups. This atypical situation may have evolved to ensure that packs don't overwhelm each other by trying to raise too many litters at once. The species is also unusual in that some members of the pack, including the males, may be left to guard the pups while the others, including the mothers, join the hunting party. The practice of leaving adults behind to guard pups can reduce hunting efficiency in smaller packs. Packs are separated into male and female hierarchies. If one of the alphas were to die, it was thought that the pack had already split, but this was disproved (albeit on a small scale) by Mutual of Omaha's Wild Kingdom, in which six dogs had previously been held in captivity (only five they arrived at the island, one died of anesthesia) lost both their alphas, to what were presumed to be crocodiles, but the pack of three remained glued together and a new male and female pair were made. The oldest will have alpha status over the others, so a mother will retain alpha status over her daughters and sisters. In the case of males, the father and dominant brother of the others will be eminent. Without a father or brother, one of the others may become the new dominant breeder. African wild dogs defer to the young, killing, letting them eat first; this can lead to the youngest male taking over a vacant alpha position without bloodshed. When two of these groups split up, they can form a group if they are not linked. Dominance is established without bloodshed, as most dogs in a group tend to be related to each other in one way or another. When this is not the case, they form a hierarchy based on submission rather than dominance. Submission and non-aggression are strongly emphasized; even over food, they'll beg vigorously rather than fight. This behavior may be due to their way of making large litters of dependent pups in which the loss of a single person to injury would mean that the hunting group might not be able to supply all the pack members. Unrelated wild dogs sometimes join packs, but this is usually temporary. Instead, unrelated wild dogs will occasionally attempt hostile takeovers. The African wild dog lives and hunts in large packs. Like most members of the canine family, it is a cursorial hunter, meaning it pursues its prey in a long, open chase. These chases can occur at speeds of up to 66 km / h for 10 to 60 minutes, and over long distances (at around 50 km / h for 5.6 km). Almost 80% of all wild dog hunts end in a kill. By comparison, the success rate for lions, often considered apex predators, is only 30%. Schaller found that 9 out of 10 wild dog hunts in the Serengeti ended in death. Members of a group vocalize to help coordinate their movements. Its voice is characterized by an unusual chirping or squeaking sound, similar to that of a bird. Wild dogs frequently kill larger prey by disemboweling them, a technique that is quick but has given this species a negative and ferocious reputation. For this reason, even some early "conservationists", such as Carl Akeley, took pride in killing whole packs of wild dogs. After a successful hunt, hunters will regurgitate meat for those who remained in the den during the hunt, including the dominant female, puppies, the sick or injured, the old and infirm, and those who stayed to guard the puppies. The wild dog's main prey varies between populations, but is always centered on medium to large ungulates, such as impala, Thomson's gazelle, springbok, kudu, toad and wildebeest. The most frequent single prey species depends on the season and local availability. For example, in the Serengeti in the 1970s, wildebeest (mostly calves) were the most frequently caught species (57%) from January to June, but Thomson's gazelle were the most frequent (79%) the rest of the year. In the Selous Game Reserve, the most frequent prey is the impala. While the vast majority of its diet consists of mammal prey, it occasionally hunts large birds, particularly ostriches. Other predators, such as lions, sometimes steal the prey that wild dogs catch. Some packs also include large animals among their prey, including zebras and warthogs; some Serengeti packs have specialized in hunting zebras in preference to other prey. The frequency and success rate of zebra and warthog hunting varies considerably between packs. To hunt larger prey, wild dogs use a closely coordinated attack, starting with a quick charge to bring down the herd. One wild dog then grabs the victim's tail, while another attacks the upper lip or nose, and the rest attempt to disembowel the animal. Male wild dogs generally perform the task of grabbing warthogs by the nose. This behavior is also used on other large, dangerous prey, such as African buffalo, giraffe calves and large antelope, even the giant one-ton elk. Studies indicate that this large-animal hunting tactic may be a learned behavior, transmitted from generation to generation in specific hunting packs, rather than an instinctive one. Some studies have also shown that other information, such as the location of drinking troughs, can be transmitted in the same way. The range of original packs varies according to pack size and terrain. In the Serengeti, the average dog density (before the local extinction of the species) was one dog per 208 km2, while in the Selous Nature Reserve, the average density was one dog every 25 km2. However, population density in the Serengeti until 1970 was as high as one dog per 35 km2 before dropping to one in 200 km2 by 1977. Their preferred habitat in the Serengeti is deciduous forest, due to the large prey herds, lack of competition from other carnivores and better calving sites. In the Serengeti, the average range has been estimated at 1,500 square kilometers, although individual ranges overlap widely. In the past, around 500,000 African wild dogs existed in 39 countries, and packs of 100 or more were not uncommon. This range once included Egypt and parts of the Sahara Desert. Now, only around 3,000-5,500 are found in less than 25 countries, or perhaps only 14 countries. They are found mainly in eastern and southern Africa, mainly in the two remaining large populations associated with Tanzania's Selous Wildlife Reserve and the population centered in northern Botswana and eastern Namibia. Smaller but apparently secure populations of several hundred individuals are found in Zimbabwe (Hwange National Park), South Africa (Kruger National Park) and Tanzania's Ruaha / Rungwa / Kisigo complex. Isolated populations persist in Zambia, Kenya and Mozambique. The African wild dog is an endangered species due to habitat loss and poaching. It uses very large territories (so can only persist in large protected areas) and is heavily affected by competition with large carnivores that depend on the same prey base, particularly the lion and spotted hyena. While adult wild dogs can generally out-compete large predators, lions often kill as many wild dogs and cubs on the brood site as possible, but don't eat them. Head-to-head, the hyena is much more powerful than the wild dog, but large numbers of wild dogs can successfully hunt a small number of hyenas because of their teamwork. It is also killed by livestock farmers and game hunters, although it is generally no more (perhaps less) persecuted than other carnivores that pose a greater threat to livestock. Most of Africa's national parks are too small for a pack of wild dogs, so packs thrive in unprotected areas, which tend to be ranches or farmland. Ranchers and farmers protect their domestic animals by killing wild dogs. Like other carnivores, the African wild dog is occasionally affected by epidemics of viral diseases such as rabies, distemper and parvovirus. Although these diseases are no more pathogenic or virulent for wild dogs, the small size of most wild dog populations makes them vulnerable to local extinction due to disease or other problems. |
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