Thomson's Gazelle

Thomson's Gazelle, often called 'Tommie,' is one of the most abundant and recognizable small antelopes of the East African plains. It is renowned for its speed, agility, and the distinctive stotting (pronking) behavior used to evade predators. Living in vast herds across the Serengeti-Mara ecosystem, it plays a key role as prey for many of Africa's large carnivores and is a symbol of the African savanna.

East Africa, primarily Kenya and Tanzania, especially the Serengeti-Mara ecosystem

Found primarily in Kenya and Tanzania, concentrated in the Serengeti National Park, Ngorongoro Conservation Area, and Maasai Mara National Reserve, with populations extending into surrounding plains and conservancies.

Altitude and depth

Typically found at elevations of 900-2000 meters in the East African plains and highlands.

Seasonal movements

Undertakes seasonal migrations following the rains, moving with wildebeest and zebra herds between short-grass plains in the wet season and taller grasslands or woodlands in the dry season.

Open short-grass plains, savanna, and semi-arid grasslands with scattered bushes; favors areas with short grass for grazing and good visibility to detect predators.

Adaptations to its environment

Highly efficient water conservation allows survival with minimal drinking water, relying on moisture from vegetation; exceptional speed (up to 80-90 km/h) and stotting behavior help evade predators; keen eyesight and hearing aid in early predator detection.

Least Concern (LC) according to IUCN, though some regional populations have declined due to habitat loss and competition with livestock; overall the species remains abundant across its range.

Estimated population

Estimated total population of around 500,000-550,000 individuals, with a generally stable to slightly declining trend outside protected areas.

Habitat loss from agricultural expansion, competition with livestock for grazing land, poaching for bushmeat, and predation pressure exacerbated by human encroachment into wildlife corridors.

Diseases and parasites

Susceptible to parasitic infections including ticks and gastrointestinal worms, as well as diseases such as foot-and-mouth disease that can affect populations in contact with livestock.

Protected within major reserves including Serengeti National Park, Maasai Mara National Reserve, and Ngorongoro Conservation Area; conservancies around these parks help maintain migration corridors and reduce human-wildlife conflict.

Recommended actions

Maintain and expand wildlife corridors connecting protected areas, reduce livestock encroachment on grazing lands, strengthen anti-poaching patrols, and support community-based conservation initiatives.

Tan to reddish-brown upperparts with a distinctive black horizontal stripe along the flanks, contrasting white underparts and rump patch; face marked with black and white stripes running from eyes to nose.

Size

Shoulder height of 55-70 cm; body length approximately 80-120 cm.

Weight

Males typically weigh 20-35 kg, females slightly lighter at 15-25 kg.

Distinctive features

Distinguished from the similar Grant's Gazelle by its smaller size, prominent black side stripe, and shorter, more lyre-shaped horns present mainly in males.

Differences between males and females

Males are larger and possess long, ridged, lyre-shaped horns (25-43 cm), while females have much shorter, thinner, sometimes absent horns.

Highly social, forming herds that can range from small family groups of females and young to large aggregations of hundreds or thousands during migration; males establish and defend territories during breeding season.

When it is active

Primarily diurnal, with peak activity during early morning and late afternoon to avoid the heat of midday.

Diet

Herbivorous grazer, primarily feeding on short grasses; will also browse on herbs, shoots, and foliage when grass is scarce, especially during dry seasons.

Communication

Communicates through visual signals like stotting and tail flicking, scent marking via preorbital glands to mark territory, and vocalizations including snorts and bleats especially between mothers and fawns.

Interactions with other species

Major prey species for cheetahs, lions, leopards, hyenas, and wild dogs; often found grazing alongside wildebeest and zebra, benefiting from shared predator vigilance during mixed-species herding.

Role in its ecosystem

Serves as a critical prey base supporting East Africa's large carnivore populations and contributes to grassland ecosystem dynamics through grazing pressure that maintains short-grass plains favored by many other herbivores.

Breeding can occur year-round but peaks with rainy seasons; gestation lasts about 5-6 months, typically resulting in a single fawn; females can breed twice a year in favorable conditions.

Raising the young

Females hide newborn fawns in tall grass for the first few weeks, visiting periodically to nurse; fawns join the herd after developing sufficient strength and speed to keep up, usually within a few weeks.

Maturity and lifespan

Sexual maturity reached at around 1-2 years of age; lifespan in the wild is typically 10-15 years, slightly longer in captivity.

Classification

Mammalia > Artiodactyla > Bovidae > Eudorcas > Eudorcas thomsonii

Subspecies

Some authorities recognize Eudorcas thomsonii thomsonii (Serengeti-Mara population) and Eudorcas thomsonii nasalis (Loita Plains, Kenya), though subspecies validity is debated.

Scientific synonyms

Gazella thomsonii; Gazella (Eudorcas) thomsonii

Recent studies

Recent research has focused on migration patterns using GPS tracking within the Serengeti ecosystem and genetic studies examining population structure and hybridization risks with other gazelle species.

Genome and DNA

Diploid chromosome number reported as 2n=58; genetic studies have helped clarify taxonomic relationships within the Eudorcas genus and its divergence from Gazella.

Compared with similar species

Similar to Grant's Gazelle but smaller, with a shorter tail, more pronounced black side stripe, and different horn shape; often found in the same habitats but Thomson's Gazelles favor shorter grass areas.

Thomson's Gazelles can reach speeds of up to 80-90 km/h in short bursts and are famous for 'stotting'—jumping stiff-legged into the air, possibly to signal fitness to predators. They are one of the primary prey species for cheetahs, the fastest land animal.

Where and how to see it

Best observed in the Serengeti National Park and Maasai Mara National Reserve, particularly during the Great Migration season (July-October) or the calving season (January-March) when large herds gather on the plains.

Risks to humans

No notable risk to humans; they are shy and avoid human contact, posing no direct threat.

Human uses

Historically hunted for bushmeat and hides by local communities; today primarily valued for ecotourism as a key species in East African wildlife safaris.

Myths and legends

In some East African cultures, gazelles symbolize grace, speed, and vigilance, often appearing in folklore as clever or swift characters that outwit predators.