Hyena

Hyenas (or hyaenas) are African and Asian dog-like carnivores in the family Hyaenidae, order Carnivora, which also includes the dogs, cats, seals, and bears. Hyenas are very powerfully built animals with a stout head, a short snout, short ears, and powerful jaws with strong teeth, useful for crushing bones to get at the nutrients contained inside. The neck of the hyena is rather elongate, and the hind legs are somewhat smaller and lower than the forelegs. The four-toed paws have nonretractable claws, used for digging their burrows, or for gripping the ground while tearing away at the carcass of a dead animal. The fur is coarse and mostly comprised of guard hairs, and some species have a relatively long mantle on the back of the neck, which can be erected as an aggressive display.

Hyenas commonly feed on carrion, and on the remains of the kills of larger predators. Hyenas find the kills of others by using their keen sense of smell, and by observing the movements of large predators and scavenging birds, such as vultures. Spotted hyenas are particularly capable predators, often hunting in packs, and can take down prey that is considerably larger than themselves, even as large as domestic cattle. Striped hyenas have been reported to scavenge human bodies that are not buried deeply enough. When wild food is scarce, the larger spotted hyena will sometimes attack and kill people.

Hyenas are social animals, living in groups and hunting and scavenging in packs. Mature female hyenas can give birth once each year, to a litter of three or four brown cubs.

Hyenas tend to be nocturnal prowling animals, usually resting near their rocky lairs or burrow openings during the day. However, they are sometimes active during the day, although not when it is intensely hot. As they move about, especially at night, hyenas commonly make diverse noises such as barking and hysterical laughing, which are unsettling to many people.

Many people consider hyenas to be ugly and offensive creatures, because of their outward appearance—a crooked-legged stance, strange face, raucous noises, rough pelage, apparent cowardice, smelliness, and scavenging habits. Hyenas are commonly considered to be pests, because they sometimes kill livestock, they occasionally attack people, and because they are just generally disliked. For these reasons, hyenas are often killed by shooting or poisoning. However, hyenas play an important role as scavengers and cullers-of-the-weak in their ecosystem. Hyenas should be respected for their provision of this valuable service, as well as for their intrinsic value as wild animals.

Pack of hyenas feeding on a zebra. Photograph by Leonard Lee Rue, III. Photo Researchers, Inc. Reproduced by permission.

The spotted or laughing hyena (Crocuta crocuta) is the largest species of hyena, occurring in open habitats throughout sub-Saharan Africa. Adults of this species typically weigh 130-180 lb (59-82 kg), and have a gray-red coat with numerous dark brown spots. The spotted hyena does not have a mane on the back of its neck. This animal is said to have the strongest jaws and teeth in proportion to its size of any animal; it can crack the largest bones of even cow-sized animals to get at the nutritious marrow inside. The spotted hyena lives in large, territory-holding groups. These animals are sometimes solitary hunters, but they usually hunt in packs.

The spotted hyena was long thought to mostly eat carrion, but closer study of the habits of this nocturnal predator has shown that it is an efficient hunter. Spotted hyenas are often seen waiting, in accompaniment with vultures and jackals, while lions eat their fill of a recently killed animal. However, in many of these cases it is likely that the hyenas actually did the killing at night, but were then quickly chased off the carcass by the lions. In these situations, the hyenas must patiently wait until the lions finished their scavenging of the hyena kill, before the actual hunter can eat.

Interestingly, in many places spotted hyenas and lions have developed a deep, mutual enmity for each other. Lions can be quite intolerant of nearby hyenas, and will often chase and sometimes kill these animals, although they do not eat them. There are also cases in which groups of hyenas have cornered individual or pairs of lions, forcing them to climb a tree for refuge, and sometimes killing the large cats. Reciprocal, lethal rivalry of this sort is rare among wild animals, but considering the feeding relationships of these particular species, it is not too surprising that this unusual behavior has developed.

It is virtually impossible to determine the sex of a spotted hyena, because the external genitalia of the female mimic those of the male, and are virtually identical in form. A traditional myth about this animal described how any hyena could act as a male or female (that is, as a hermaphrodite), and this was why these animals laugh so raucously.

The striped hyena (Hyaena hyaena) ranges from central Africa to southwestern Asia and Asia Minor. It weighs about 59-119 lb (27-54 kg), and has a gray coat with darker stripes and a dark mane. The brown hyena (Hyaena brunnea) is a closely related, similar-sized species with a rather long, heavy, uniformly brown coat and mane. The brown hyena occurs in southern Africa. This species is becoming quite rare because it is being exterminated by farmers, who erroneously believe that the brown hyena preys on livestock.

Both of these species are considerably smaller and less powerful than the spotted hyena, and they are not very social animals, foraging as individuals or in groups of two. The striped and brown hyenas are nocturnal, and feed mostly on carrion, crushing the bones to obtain nourishment from even the most picked-over carcass. They also occasionally prey upon small mammals. The aardwolf (Proteles cristatus) is an uncommon, hyena-like animal of the grasslands and savannas of southern and eastern Africa. This species is much smaller and less powerful than the true hyenas. The jaws and teeth of the aardwolf are relatively small and quite unlike the bone-crushing apparatus of the hyenas, but useful in feeding on small, soft prey such as the insects that are the main food of this animal. The fur of the aardwolf is relatively long and yellow-gray, with dark stripes, an erectile mane, and a bushy, black-tipped tail. The aardwolf lives in burrows that it usually excavates itself, a trait that is likely the origin of its common name, which is derived from the Afrikaans words for "earth wolf." The aardwolf largely feeds nocturnally on termites and the larvae of other insects, although it sometimes feeds on carrion, and may occasionally prey on small animals. If cornered by a threatening predator, the aardwolf emits a foul-smelling scent from its anal glands as a means of self-defense.