Kob
Although still numerous in western Uganda, the kob
is far less common now in other areas of East Africa. It was once
found in western Kenya and northern Tanzania but has not been seen
there in recent years. Kobs do still range across sub-Saharan Africa.
Physical Characteristic
The kob is similar in appearance to the impala, but the two species
are not related. The Ugandan kob generally is reddish-brown, but other
subspecies range from light brown to almost black. The underside of
the body is white, a white ring appears around each eye, and a white
patch or chevron appears on the throat; a black stripe runs down the
front of each foreleg. Horns occur only in males, and though lyre-shaped,
they are shorter, thicker and ringed almost to the tip.
Habitat
Kobs are ecologically restricted, preferring low-lying
flats or gently rolling country free of seasonal extremes and close
to permanent water. They compete for these lands with humans, who
need them for farming.
Behavior
The social structure of the kob is based on small herds
that come together into larger groups of up to 1,000 animals. These
large groups will contain 30 to 40 breeding males that hold territories.
Like many other antelope species, breeding only occurs within areas
controlled by an individual territorial male. But the kob, unlike
other antelopes, has taken the system a step further by establishing
permanent breeding grounds, some of which have been in continuous
use for at least 50 years.
Closely spaced breeding territories where almost all mating takes
place are called leks. Lekking grounds, usually located on a knoll
or elevated area near water, are roughly circular in shape and from
20 to 100 yards in diameter. Different males occupy these areas
throughout the year. Females move freely over the general area,
but when they are in heat they go directly to the breeding grounds
to mate.
Three or four of the innermost territories seem to be the most
sought after by the females, where activity is intense. Apparently
it is the concentrated deposits of hormone-rich urine that attracts
them, rather than a specific male. The holder of a territory is
constantly being challenged. If he loses his territory, either through
a fight or by leaving it to graze or drink, he joins a bachelor
herd of males. When he recovers his strength, he will try to regain
his territory.
Other aspects of the social organization are similar to those of
other medium-sized antelopes, in which there are also territorial
males, free-roaming herds of females with their young and herds
of bachelor males. If dry season forces a move, kobs may dispense
with this system and adopt one where males and females assemble
and move as one large body.
The pre- and postmating behavior of kobs is also different from
that of other antelopes. The male is not as rough with the female
and does not attempt to force her to stay within his territory-rather
he appears to try gently to convince her. He makes soft noises during
courtship play, repeatedly whistling through his nostrils after
mating. The sound carries across the breeding grounds and may be
echoed by the other territorial males.
Diet
Kobs often associate with larger animals such as
hippos, buffalos, topis and hartebeests. These animals help keep the
grass short, as the kob prefers. Like reedbucks and waterbucks, kobs
develop attachments to particular localities, returning to the same
grazing areas and watering places day after day, season after season.
Caring for the Young
The single newborn is suckled for 6 to 7 months
and at the time of weaning has reached half of adult size. Young males
begin to grow their horns at 5 months, and by 1 year the horns are
about as long as the ears. Kobs become sexually mature between 13
and 14 months, but a male will not be active in the breeding grounds
until he is 3 or 4 years old, when he has become strong enough to
vie for a territory.
Predators
During the first 7 months of life, the mortality
rate is high, with only about half of the kobs surviving predators
such as lions, leopards, spotted hyenas and hunting dogs. When threatened,
the solitary kob will lie flat and still or take to water to escape
its hunters.
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