The [P 020 / Thomson's gazelle], commonly referred to as Tommy, is the second most numerous [G 22 / herbivore] in the Serengeti region. Its current population is estimated at 500,000. The Tommy is a species of antelope and belongs to the same family as the wildebeest.
Its hair is short and sandy brown with a large jet-black band which extends horizontally on the sides and vertically on the flanks. The underside and rump are white. The black band serves as a alarm signal to other gazelles. The muscles in the sides vibrate when the animal senses danger. The coloration of the Tommy serves as camouflage and recognition, in the same way stripes serve the zebra.
Despite their excellent camouflage, speed and keen sensory perception, Tommies fall victim more frequently than any other herbivore on the plains. They are the primary prey of wild dogs and [V 002 / cheetahs] which take a heavy toll on the plains. When they migrate to the west in the dry season, the cheetahs follow. Lions and [P 007 / leopards] prey on gazelles during the dry season. [I 008 / Jackals], eagles and some species of vulture prey heavily on newborn fawns.
Like the wildebeest, gazelles mate in breeding territories staked out and defended by territorial males. Unlike the wildebeest, the gazelle breeds twice a year, has less distinct peak birth periods and gives birth in isolation. The pregnant female will give birth in a sheltered spot away from the herd. Once the mother has cleaned the newborn and eaten all evidence of birth, she rejoins the female herd leaving the newborn for several hours before returning.
Instinctively, newborn fawns are docile and usually remain
quiet and motionless for the first couple days because any movement would give away their presence to predators. The instinct to flee when it is threaten is not yet developed and even if it were, its legs a too fragile to permit fast movement. This is in marked contrast to wildebeest calves which run with their mothers within the first 10 minutes.
This small species of antelope, named for the first European to explore the region, is about three feet tall and weighs 35 to 65 pounds. The Thomson's gazelle is about half the size of the other species of gazelle in the region, the Grant's gazelle.
