Aardwolf and Hyenas: Hyaenidae

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AARDWOLF AND HYENAS: Hyaenidae

SPOTTED HYENA (Crocuta crocuta:): SPECIES ACCOUNTS
AARDWOLF (Proteles cristatus): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

The spotted hyena (hi-EE-nah) is the largest of three species that include the striped and brown hyenas. Hyenas weigh about 57 to 190 pounds (26 to 86 kilograms). The aardwolf (ARD-wolf), included in the Hyaenidae family, weighs about 20 to 30 pounds (9 to 14 kilograms). All hyaenids (members of the Hyaenidae family), except the spotted hyena, have long, shaggy coats. A mane of hair down the back can be erected to make the animals look larger. All have a bushy tail and a sloping back. Anal gland secretions are used for marking territories. Spotted hyena females have genitals resembling those of males.

GEOGRAPHIC RANGE

Hyenas and aardwolves are found in the Middle East (including Turkey, Israel, and Saudi Arabia), Pakistan, India, and in Africa south of the Sahara Desert (except the rainforests of The Democratic Republic of the Congo).

HABITAT

Hyenas and aardwolves occupy grasslands, bush country (wild, uncultivated land), and open woodlands. They dig burrows (holes) underground or live in burrows abandoned by other animals.

DIET

The striped and brown hyenas are mainly scavengers, feeding off the leftover kills of other animals. They also eat hares (relatives of rabbits), rodents, reptiles, vegetables, and fruits. Brown hyenas along the Namib Desert eat South African fur seal pups and other sea organisms. The spotted hyena mostly hunts its own prey, such as gazelles, antelopes, wildebeests, and zebras. Aardwolves feed almost exclusively on termites.

BEHAVIOR AND REPRODUCTION

Spotted and brown hyenas live in groups called clans, dominated by a female. Striped hyenas are solitary, but small family groups may share a den. Females of spotted and brown hyenas stay with the clan for life. Male spotted hyenas are driven from the clan upon puberty, while male brown hyenas may choose to stay with the clan or leave. Hyenas scent mark territories by depositing anal secretions on grass stalks. Aardwolves are solitary, although, like hyenas, they communicate through scent marking. Hyaenids are active at night or at dawn and dusk.

Spotted and striped hyenas breed year round, while brown hyenas are seasonal breeders. Litter size varies, with one to two cubs for the spotted hyena, up to four for the striped hyena, and as many as six for the brown hyena. Brown and striped hyenas wean their young at about one year, while the spotted hyena nurses for up to a year and a half. Aardwolves may be seasonal or nonseasonal breeders, giving birth to two to four cubs, who leave home by age one.

HYAENIDS AND PEOPLE

Some African cultures believe hyenas possess magical powers. Others consider hyenas as pests for preying on domestic livestock. The brown hyena is a popular exhibit animal in zoos. In Africa, garbage is left out for the spotted and striped hyenas to eat. Aardwolves are useful to humans for eating termites.

PULLING RANK

Among spotted hyenas, rank is passed on by mothers to their female offspring. In the communal den, a dominant female's cub learns from her mother which clan members she can push around. A dominant female will attack a subordinate female, which encourages her offspring to do the same. After repeated aggressive displays by her mother, the cub starts bullying the offspring of subordinate females. The dominant female participates in the bullying.

CONSERVATION STATUS

The World Conservation Union (IUCN) lists the brown and striped hyenas as not currently threatened, but may become threatened because of, among other things, accidental killing from the poison-spraying of pests. The spotted hyena also may become threatened because of killing by humans and habitat loss or degradation as a result of land clearing for agriculture and livestock. The aardwolf is not a threatened species.

SPOTTED HYENA (Crocuta crocuta:): SPECIES ACCOUNTS

Physical characteristics: Spotted hyenas range in color from sandy to brown, with black or dark brown spots. The short, bushy tail is black. The sloping back, caused by front legs that are longer than the hind legs, allows for long-distance pursuit of prey. The massive jaws can crush bones, teeth, hooves, and horns. The neck and back are covered with a short mane of hair that can be raised to make the hyena seem larger.

Females are larger than males. In southern Africa, females weigh up to 190 pounds (85 kilograms) and males up to 135 pounds (60 kilograms). Eastern African hyenas are lighter, with females weighing about 125 pounds (55 kilograms) and males about 110 pounds (49 kilograms). The female's genital organ resembles that of the male

because of overproduction of testosterone, the male hormone responsible for the development of the penis. The female mates and gives birth through her pseudopenis (SUE-doh-pee-nis).

Geographic range: Spotted hyenas are found in Africa in countries such as Chad, Sudan, Angola, Zambia, and Zimbabwe.

Habitat: Spotted hyenas prefer grasslands inhabited by their herbivorous (plant-eating) prey, such as antelopes and wildebeests. They also occupy woodlands and semi-deserts.

Diet: Spotted hyenas mostly hunt rather than scavenge food. They prey on animals several times their size, including gazelles, antelopes, wildebeests, and zebras. They also eat the young of giraffes, hippotamuses, and rhinoceroses, as well as reptiles, domestic livestock, and human garbage. They tear pieces of flesh from prey, killing it in a few minutes. They eat very fast, consuming flesh, skin, teeth, bones, horns, and even hooves. A hyena can eat 33 pounds (15 kilograms) of meat per feeding, throwing up indigestible food as pellets.

Behavior and reproduction: Hyenas live in clans of as many as eighty members, ruled by a dominant female. Daughters inherit their mothers' status. Males are submissive to all females and to the dominant female's offspring. Young males are expelled from their homes between ages two to four. They join other clans, starting at the lowest rank. Sons of dominant females may be allowed to stay longer and are more likely to become dominant males in the clan they join. Female members occupy the same territory, defending it against intruders, sometimes to the death.

Spotted hyenas are either nocturnal (active at night) or crepuscular (active at dusk and dawn). They hunt alone, although they will join forces to catch large prey. They chase down their prey, running 25 to 31 miles (40 to 50 kilometers) per hour and covering a distance of up to 3 miles (5 kilometers). They target young, old, and sick animals.

The spotted hyena is also called the "laughing hyena" because of its high, cackling laugh. It laughs when it is being chased or attacked or to show submission. Hyenas whoop to call clan members to defend territory or to hunt. Greetings involve sniffing each other's genital areas. They scent-mark territories with anal secretions and feces.

Adults get together only to mate, which may be at any time of the year. A long pregnancy (up to four months) results in well-developed cubs, usually one or two, born with teeth and able to walk. Cubs are kept in a small den inaccessible to adults and predators. When female cubs come out to nurse, they compete for their mother's milk, sometimes resulting in the death of the sibling who cannot nurse. Within the den, cubs may kill littermates during fights for dominance. After two to four weeks, the mother takes her young to a communal den, where cubs of all ages are raised together. Mothers do not nurse each other's young. Cubs learn to recognize clan members and establish social rankings. They are weaned from their mothers' milk at about fourteen to eighteen months. Males do not share in parenting.

Spotted hyenas and people: Some African cultures believe hyenas possess magical powers. Humans kill hyenas for preying on domestic livestock.

Conservation status: The IUCN lists the spotted hyena as Lower Risk/Conservation Dependent (could become threatened) due to killing by humans and habitat loss or degradation as a result of land clearing for agriculture and livestock. ∎

AARDWOLF (Proteles cristatus): SPECIES ACCOUNTS

Physical characteristics: The aardwolf is yellowish white to reddish brown, with several black stripes along the body and legs. A dark mane running from the back of the head down to the tail can be erected to make the aardwolf seem bigger. A sloping back results from hind legs that are longer than the forelegs. The teeth are very small and widely spaced. The spatula-shaped tongue and sticky saliva are adapted for licking up termites. Sharp canine teeth are designed for fighting enemies. Both sexes are about the same size, about 20 pounds (9 kilograms) in southern Africa and up to 30 pounds (14 kilograms) in East Africa.

Geographic range: Aardwolves are found in Africa, including South Africa, Botswana, Zambia, Kenya, and Somalia.

Habitat: Aardwolves prefer grassland, open country, and rocky areas, where they live in burrows they have dug up or taken from aardvarks or springhares.

Diet: Aardwolves feed primarily on two varieties of termites that forage on the ground surface. They can eat about 200,000 termites a night. They also eat other insects, small birds, eggs, mice, and carrion (dead or decaying animal flesh).

Behavior and reproduction: Aardwolves are solitary, feeding at night when their favorite termites emerge. When these termites become inactive in winter, aardwolves switch to another termite species that are active in the late afternoon. When scared or threatened, aardwolves roar and growl. They scent mark territories by depositing anal secretions on grasses. Aardwolves within the same territory erect their back hair until they recognize each other. Mothers and young sniff each other's noses to establish identity. Aardwolves generally mate with just one partner, although a dominant male may mate with the partner of a subordinate male. The litter consists of two to four cubs. Males babysit the young, guarding the den against predators when the mothers feed. The young leave home by one year of age.

Aardwolves and people: Aardwolves may be hunted as a food source. They sometimes are poisoned when pesticides are sprayed to control locusts in some areas.

Conservation status: Aardwolves are not a threatened species. ∎

FOR MORE INFORMATION

Books:

Angier, Natalie. "Hyenas' Hormone Flow Puts Females in Charge." In The Science Times Book of Mammals. New York: The Lyons Press, 1999.

Estes, Richard D. The Behavior Guide to African Mammals: Including Hoofed Mammals, Carnivores, Primates. Berkeley, CA: The University of California Press, 1991.

Ewer, R. F. The Carnivores. Ithaca, NY: Comstock Publishing Associates, 1998.

Mills, Gus, Heribert Hofer, and IUCN/SSC Hyaena Specialist Group. Status Survey and Conservation Action Plan: Hyaenas. Gland, Switzerland, and Cambridge, U.K.: IUCN, 1998.

Morgan, Sally. Hyenas. Austin, TX: Raintree Steck-Vaughn Publishers, 2003.

Nowak, Ronald M. "Striped and Brown Hyenas." Walker's Mammals of the World Online 5.1. Baltimore: Johns Hopkins University Press, 1997. http://www.press.jhu.edu/books/walkers_mammals_of_the_world/carnivora/carnivora.hyaenidae.hyaena.html (accessed on June 21, 2004).