Hyena
The hyena is Africa's most common large carnivore.
Over the years hyenas and humans have come into close contact in Africa
and, in earlier times, in Asia and in Europe, often leading to mutual
predation. In ancient Egypt hyenas were domesticated, fattened and
eaten, and in turn humans have on occasion become food for hyenas.
Reputed to be cowardly and timid, the hyena can be bold and dangerous,
attacking animals and humans.
Physical Characteristic
Of the three species of hyena in Africa, only the spotted hyena and
the shy and much rarer, striped hyena (Hyaena hyaena) are found in
East Africa. The smaller, and even shyer brown hyena (Hyaena brunnea)
occurs only in southern Africa. Different from most other animals,
female spotted hyenas are dominant over the males and outweigh them
by about 3 pounds.
It is difficult to distinguish male and female hyenas by observation
in the field. They are not hermaphrodites (having both male and
female sexual organs), nor can they change their sex at will, as
many people believe. Although the external female genitalia have
a superficial similarity to those of the male, they are nonetheless
female organs and only the females bear and nurse young. Why the
female hyena developed in this manner is not known, but it may have
been necessary for them to appear large and strong to protect their
young from males, as hyenas have cannibalistic tendencies.
Habitat
Spotted hyenas are found in grasslands, woodlands,
savannas, subdeserts, forest edges and mountains.
Behavior
Spotted hyenas are organized into territorial clans
of related individuals that defend their home ranges against intruding
clans. The center of clan activity is the den, where the cubs are
raised and individuals meet. The den is usually situated on high ground
in the central part of the territory. Its above-ground entrances are
connected to a series of underground tunnels.
Hyenas mark and patrol their territories by depositing a strong-smelling
substance produced by the anal glands on stalks of grass along the
boundaries. "Latrines," places where members of a clan
deposit their droppings, also mark territories. The high mineral
content of the bones hyenas consume make their droppings a highly
visible, chalky white. Hyenas are social animals that communicate
with one other through specific calls, postures and signals. They
quickly make their various intentions known to other members of
the clan, or to outsiders. When a hyena's tail is carried straight,
for example, it signals attack. When it is held up and forward over
the back, the hyena is extremely excited. In contrast, it hangs
down when the hyena is standing or walking leisurely. If frightened,
the hyena tucks its tail between the legs and flat against the belly
and usually skulks away.
Diet
The spotted hyena is a skillful hunter but also
a scavenger. Truly an opportunistic feeder, it selects the easiest
and most attractive food it may ignore fresh carrion and bones if
there is, for example, an abundance of vulnerable wildebeest calves.
It consumes animals of various types and sizes (including domestic
stock and even other hyenas), carrion, bones, vegetable matter and
other animals' droppings. The powerful jaws and digestive tract of
the hyena allow it to process and obtain nutrients from skin and bones.
The only parts of prey not fully digested are hair, horns and hooves;
these are regurgitated in the form of pellets. As hyenas hunt mostly
at night and devour all parts, little evidence remains of their actual
meals. Although they eat a lot of dry bones, they need little water.
Caring for the Young
Hyenas usually bear litters of two to four cubs,
which, unlike the other two species, are born with their eyes open.
Cubs begin to eat meat from kills near the den at about 5 months,
but they are suckled for as long as 12 to 18 months, an unusually
long time for carnivores. This is probably a necessity, as most kills
are made far from the den, and hyenas, unlike jackals and hunting
dogs, do not bring back food and regurgitate it for their young. At
about 1 year, cubs begin to follow their mothers on their hunting
and scavenging forays. Until then, they are left behind at the den
with a babysitting adult.
Predators
Lions (who will attack them at every opportunity),
hunting dogs and strange hyenas are among the species that prey on
hyenas.
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