Masai Mara Animals - A guide for a Photographic Safari in the Masai Mara

Named after explorer Joseph Thomson -and often referred to as the "tommy"- this small gazelle keeps the unpleasing privilege of being the cheetah's favourite prey. One of the most well known gazelles, they live in Africa's savanna and grassland habitats, particularly the Serengeti region of Kenya and Tanzania. They eat low vegetation and grass, with most of their water needs coming from what they eat.

Thomson's gazelles are 60-90 cm tall and weigh 30-35 lbs. They have light brown coats with white underparts and a distinctive black stripe. Their horns are long and pointed with slight curvature. A noticeable behaviour of Thomson's gazelles is their bounding leap, known as stotting or pronking, used to startle predators and display strength. They often congregate with other hoofed mammals, or ungulates, such as wildebeests, zebras, and Grant's Gazelle, and usually live and migrate in herds with hundreds or thousands of other Thomson's gazelles.

The social structure of gazelles consists of several types of groups. Male gazelles are territorial throughout their adult lives, though not usually before 2-3 years of age. Also periods of territoriality will be interspersed with periods on non-territoriality. During the non-territorial periods males usually spend their time in bachelor groups or as part of a mixed herd. Likewise females will form migratory female groups that travel through the males' territory. As the female groups pass through, the territorial males will try to herd them to prevent them from leaving and to engage in coitus. Adult male bucks with adjoining territories will engage in combat several times a day, fighting with their horns to establish dominance and the boundaries of their territories. In this way, the accepted boundaries of the territory can change on a daily basis. If a lone male, a bachelor group, or in some cases even an adolescent male fawn of a female gazelle should be passing through a territorial male's region, the male will chase the offender out of his territory. Interestingly, this territoriality does not extend to males of other species. The territory of a Thomson's gazelle and several other types of ungulates may overlap with no problem whatsoever. Occasionally, a Thomson's gazelle and a zebra or other ungulate will even appear to enjoy one another's company with great sociability.

Female Thomson's gazelles give birth to single fawns after a 5-6 month gestational period. They are unusual among other ungulates in that they can give birth twice yearly, rather than just once.

In the wild, Thomson's gazelles can live up to 10-15 years, although they are preyed on by most African big cats and hyenas, and are the favorite food for cheetahs. Half of all the fawns born will be lost to predators before reaching adulthood. The cheetah and the Thomson's gazelle are the two fastest animals on land, with cheetahs able to attain higher speeds, but Thomson's gazelles able to outlast the cheetahs in long chases and able to make turns more speedily.