
Physical Characteristics
The Thomson's Gazelles are the most common gazelles in East Africa
but not as widely distributed as the Grant's Gazelle. Though their numbers
have diminished in some areas, they have persisted on
ranches and farmlands long after other species have disappeared.
One of the most common gazelles in East Africa, the graceful
Thompson's gazelle has shared similarities to the similarly colored Grant's gazelle
and can distinguished from Grant's gazelle by the
dark stripe that runs from the shoulder to the flank and the white
patch on the rump, as well as its smaller size. Male Thompson's
Gazelles are
larger than females and have strongly ridged horns that curve
backwards, with the tips curving forward. Female Thompson's Gazelles have short,
smooth, pencil-slim horns, or none at all. The face is accented by a
black stripe running down from the eye, a dark marking on the nose
and a light patch on the forehead.
Habitation
Although more reliant on water than Grant's gazelle, the Thompson's
gazelle has
adapted to the open plains and grasslands of southern Kenya and
northern Tanzania.
Behavior and Habits
The strongest Thompson's Gazelle males set up territories in home ranges using
an exaggerated display posture and marking boundaries with scent
gland secretions. The females and their immature offspring form
groups of 5 to 50 that wander through male territories. The
groups change members and numbers from hour to hour, so no obvious
patterns of hierarchy or leadership emerge.
The relatively silent Thompson's Gazelles rely on visual awareness of one
another to stay in contact. Their distinctive coloring may help—they
can contract the skin so the black side stripe becomes more obvious.
They also stamp their front feet to signal when they are disturbed.
Thompson's Gazelles breed twice a year. Although births occur throughout the
year, they peak right after rainy seasons. After giving birth the
mother hides the newborn in the grass, returning several times a day
to nurse it. With their tawny coloring and ability to remain
motionless for long periods, the young are surprisingly invisible
when hidden in open country.
Nevertheless, predation on the young is heavy, and many predators
feed on nothing else during the calving peaks.
Diet
Thompson's Gazelles congregate with Grant's gazelle and with larger ungulates
such as wildebeest and zebra and even cattle, which trample and
graze on tall grass, making it easier for the Thompson's Gazelle to feed on
short grass. Although grasses make up about 90% of the Thompson's
Gazelle's diet
in dry season, it also eats seeds and browses on shrubs. When the
tiny new green shoots of grass begin to grow in areas that have been
burned, Thompson's Gazelles often gather in large numbers to feed.
Predators and Threats
Thompson's Gazelles are often found on ranches and farmlands after many animals
have left, subsisting on the short grasses exposed by the cattle.
There, they are often shot or snared for the pot.
Thought You Should Know
-
The Thomson gazelle is exceptionally alert to sounds and
movements, and its fine senses of hearing, sight and smell balance
its vulnerability on the open plains.
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Males vigorously defend their territories. If challenged, the
defending male and his rival clash horns, with the winner claiming
the territory.