Selous, Tanzania
The Selous Game Reserve is a unique and unusual safari environment in Southern Tanzania; a vast, thriving wildlife area of forests and woodlands around the lagoons, sandbanks and lakes of the Rufiji River.
The Selous is Africa's largest protected area uninhabited by man, where Tanzania's greatest population of elephants wanders in an area bigger than Switzerland! The Selous(pronounced “Seloo”) is considered important enough to be World Heritage Site, in which the lucky few can experience a safari in absolutely wild and unspoiled bush. The Reserve is named after Englishman, Frederick Courtney Selous - conservationist, hunter, explorer and author, whose adventure books on Africa became best sellers in Victorian England.
The park varies from rolling grassy woodlands and plains, to rocky outcrops cut by the Rufiji River - the lifeblood of the Reserve, whose waters attracts elephant herds, and are packed full of grunting hippopotami and yawning crocodile. The banks attract large herds of plains game depending on the season, dispersing after the rains and regrouping when the water sources concentrate.
The Selous contains about one third of all the wild dogs (often called painted dogs), in the world. Their need to roam vast areas and their formidable hunting skills have caused many to be shot by farmers, but here in Selous they have boundless woodlands and savannas in which to roam. The African Wild Dog is a medium-sized canine found only in Africa, especially in savannas and other lightly wooded areas. It is also called the Painted Dog, Painted Hunting Dog, African Hunting Dog, the Cape Hunting Dog, the Spotted Dog, the Ornate Wolf or the Painted Wolf in English, and Mbwa mwitu in Swahili.
Adults typically weigh 17-36 kilograms. 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 for a total of 42 teeth. The premolars are relatively large compared with those of other canids, allowing it to consume a large quantity of bone, much like hyenas.
The African Wild Dog reproduces at any time of year, although mating peaks between March and June. Litters can contain 2-19 pups, though 10 is the most usual number. The typical gestation period is approximately 70 days. 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.
In packs, there are separate male and female hierarchies that will split up if either of the alphas dies. In the female group, the oldest will have alpha status over the others, so a mother 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 bloodshed, as most dogs within a group tend to be related to one another in some way, and even when not this can occur.
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. Lions, the top predator, only 30%. 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, the very old that cannot keep up, or those who stayed back to watch the pups.
The African Wild Dog's main prey varies among populations but always centers around medium-sized ungulates, such as the impala, their favorite ,Springbok and young wildebeest. While the vast majority of its diet is made up of mammal prey, it sometimes hunts large birds, especially ostriches. Other predators, mainly lions, sometimes steal the prey that Wild Dogs catch. 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.
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. In the Serengeti, the average range has been estimated at 1,500 square kilometres (580 square miles), although individual ranges overlap extensively. 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. 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. 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 decreases hunting efficiency in smaller packs.
There were once approximately 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 18 countries. 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 human overpopulation, 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. Hyenas usually follow them to steal their kills. One on one the hyena is much more powerful than the Wild Dog but a large group of Wild Dogs can successfully chase off a small number of hyenas because of their teamwork. 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.
The alarming decrease of numbers and their social patterns, and possibilities to observe them in such limited habitats is what has made this animals become a sort of legend and top objective of wildlife lovers when visiting the Selous Game Reserve in Southern Tanzania.
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