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Social Behavior
African wild dogs are highly social carnivores that live in packs. Differences in the degree of sociality between wild dogs and gray wolves (distant cousins of wild dogs) are reflected in a number of ways. One is in resting patterns in which wild dogs maintain physical contact or relatively short distances between individuals. Also, unlike wolves, they typically disperse in groups. Lone dogs and peripheral pack members are extremely rare. Pack living is obligatory. Compared to wolves, aggression is generally muted. A high degree of cooperation is key to survival and reproduction.
Pack formation in wild dogs is a social process that usually involves more than two individuals. Although this formation affects both individual fitness and population dynamics, and therefore is highly relevant to the conservation of this endangered species, little is known about the process in the wild and the proximate mechanisms that influence outcomes.
Typically same-sex
relatives emigrate and join opposite-sex groups. Our observations
in the field suggest that group compatibility can influence whether
stable reproductive units form. When opposite-sex groups join, they
undergo what has been termed a "trial courtship" that may
or may not result in the formation of a stable reproductive unit.
If a new pack does not stay together, it annuls. Any given instance
of pack annulment may be due to one or more causal factors that vary
both temporally and regionally. An analysis of resting patterns suggests
that spatial relationships mirror the relative strength of social
bonds and thus the degree of social integration between females and
males. In newly formed packs, same-sex associations were more common
in those that eventually annulled, suggesting that opposite-sex members
were incompatible.
Reproduction
A pack consists of any group of wild dogs with a potentially reproductive pair. Packs are typically composed of related females, related males, and pups. If a pack contains more than two adults, the reproductive pair consists of the dominant male and female. Usually only the dominant pair breeds and subordinate members help care for pups. The breeding female selects a den site, such as an abandon aardvark hole, and then contours the underground chamber prior to giving birth. The average litter size is about 8 pups. When pups are about three weeks old, they appear above ground pug-nosed with black and white coloration, and small ears that readily develop into oversized proportions. Yellow markings begin to appear at four weeks. Babysitters keep a close eye on them while other family members hunt and return to the den to regurgitate food. Pups are moved to different dens during the season. When pups are around 10–12 weeks old, packs resume their nomadic way of life. By the time the pups are about 4 months, they are already familiar with what is expected as pack members.
Hunting
Although wild dogs will sometimes hunt at night during certain phases of the moon, they usually rest during the heat of the day and hunt in the early morning and evening. The fact they are one of Africa's most successful hunters is due largely to their high degree of cooperation. When chasing down prey they can run up to 60 km/h. In more enclosed habitats, packs tend to split into hunting groups, with single dogs often taking down prey before leaving it to bring back other pack members to feed. Pups are the first to eat. Prey preferences vary regionally. Spotted hyenas sometimes follow wild dogs on hunts and try to steal their kill.
Vocalizations
Preceding a hunt, pack members typically rally in at least one greeting ceremony before setting off. It usually begins with a single dog running up to one or more dogs with head held shoulder height, mouth agape, and ears folded back, often while whimpering or whining. During a high-intensity ceremony many other different kinds of sounds are made, including squeals and high-pitched bird-like sounds called "twitters."
When filtering through thick bush pursuing prey, pack members often become separated and sometimes call to reunite. These short repetitive contact calls or "hoos" are low-pitched and delivered with the head held lower than the shoulders, frequently while running. In contrast, wolf contact howls are mostly long unbroken streams sent with the muzzle held high when standing still.
