GAME RESERVES

Thomson’s gazelle

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Thomson’s gazelles are found in numbers exceeding 550,000 in Africa and are recognized as the most common type of gazelle in East Africa. This gazelle is the most common in East Africa. Thomson’s gazelle (Scientific name: Eudorcas thomsonii) is one of the best-known gazelles. Thomson’s gazelle is the smallest, daintiest and fastest of all gazelles. It is the fifth-fastest land animal, after the cheetah (its main predator), pronghorn, springbok, and wildebeest. The Thomson’s gazelle can reach speeds of 50–55 miles per hour (80–90 km/h).

The Origin of the Name

Thomson’s gazelle is named after the Scottish explorer Joseph Thomson; the first recorded use of the name dates to 1897. Another common name for the gazelle is “tommy”. In east Africa two groups are identified: Serengeti Thomson’s gazelle ranges from the Serengeti to the Kenya Rift Valley. And eastern Thomson’s gazelle ranges from east of the Rift Valley in Kenya and Tanzania, southward to Arusha District (Tanzania) and then southwestward to Lake Eyasi, Wembere River, and Shinyanga.

Physical Distinguishing Characteristics

Thomson’s Gazelles have slender legs and a short, black tail which is constantly in motion swinging back and forth like a window blade wiper. They have large ears and eyes and a narrow muzzle. Their heads are small and they have a lightweight body which enables them to run fast and make sharp turns. To make up for their vulnerability out on the plains, gazelles have an excellent sense of hearing which makes them exceptionally alert to sounds. They also have excellent smell and sight which is their main source of communicating with each other.

Male gazelles are called ‘bucks’ and female gazelles are called ‘does’.

Thomson’s Gazelles have a thin black stripe on their face which runs down from the eye, a dark marking on their nose and a pale patch on their forehead. Males have long pointed horns which are marked with around 20 rings and are curved backwards with the tips curving forwards. Females have either no horns at all or small, short, slim horns.

Thomson’s Gazelles are 70 – 90 centimetres in length and 60 – 90 centimetres tall. They weigh around 12 – 85 kilograms (26 – 187 pounds). Male Thomson’s Gazelles are slightly larger than females. These attractive gazelles have a light brown coat and white underparts. They can be distinguished from the Grant ’s gazelle by their dark stripe which extends across their flanks. Their rump is white which extends to just underneath their tale.

Similarity to Grant’s gazelle

Thomson’s gazelle is related to Grant’s gazelle. The Grant’s gazelle is a species of gazelle distributed from northern Tanzania to South Sudan and Ethiopia, and from the Kenyan coast to Lake Victoria. Its Swahili name is swala granti. It was named for a 19th-century Scottish explorer, Lt Col Grant. Like most gazelles, they are a migratory species but are especially fond of open grass plains, and although they frequent bushy savannas, they avoid areas of high grass.

Grant’s gazelle shows high genetic variation among its populations, though there is no geographic isolation. The differentiation of the species may have evolved during repeated expansion and contraction of arid habitats during the late Pleistocene era in which populations were possibly isolated.

Fun Facts of Grant’s gazelle

  1. Grant’s live in herds of 10 to 200 individuals depending upon food availability.
  2. Adult males are seen as the largest gazelle concerning body weight.
  3. Grant’s have the ability to vary their body temperature in order to conserve water. Raising the body temperature during the day when it’s the hottest causes the animal to sweat less, thus losing less precious water.
  4. Bucks maintain territories of about 500 to 2000 meters in diameter. They are territorial, marking their space with urine and feces. The highest-ranking males will maintain the most “attractive” territories (those with the most vegetation or areas nearest the main water sources, etc.).
  5. Taking advantage of its ability to go long periods without water, Grants often extend their range into regions where they don’t have to compete with herbivores that have to eat regularly.
  6. Some herds are known to migrate in the opposite direction of the main migration since it is not necessary for them to follow the rains.

Thomson’s gazelle Habitat

Thomson’s Gazelles are found on dry, grassy plains in Sudan, Tanzania and the serengeti areas of Kenya. They prefer grasslands and shrubby steppes with heavily grazed, trampled grass. The gazelles can remain on pastures long after larger herbivores have left.

Thomson’s gazelle lives in Africa’s savannas and grassland habitats, particularly the Serengeti region of Kenya and Tanzania. It has narrow habitat preferences, preferring short grassland with dry, sturdy foundation. It does, however, migrate into tall grassland and dense woodland.

Thomson’s gazelle Diet

Thomson’s Gazelles are herbivores. Thomson’s Gazelles feed upon grass and other low vegetation. They will also browse on shrubs. Most of their required water comes from the vegetation they eat although they rely more on water than the Grant’s gazelle. Thomson’s Gazelles gather in large herds to feed, perhaps because of safety in numbers. They will also congregate with wildebeests, zebra and cattle as these larger animals will trample tall grasses making it much easier for the gazelle to eat the short grass.

Gazelles are mixed feeders. In the wet seasons, they eat mainly fresh grasses, but during the dry seasons, they eat more browse, particularly foliage from bushes, forbs, and clovers. Thomson’s gazelles are dependent on short grass. Their numbers are highly concentrated at the beginning of the rains since the grass grows quickly. They follow the larger herbivores, such as plains zebras and blue wildebeests as they mow down the tall grasses.

Thomson’s gazelle Behaviour

The gazelle is a main food item of many savanna predators such as lions, leopards, hyenas, hunting dogs and cheetahs. Thomson’s Gazelles are very fast little animals and can sometimes outrun their predators. During their initial flight from their attackers, a gazelle may sprint at up to 80 kilometres per hour (50 miles per hour) for around 15 – 20 minutes. These impressive sprinters also run in special ways to communicate with the rest of their herd and confuse their pursuer. As the gazelles race along in their escape, they perform sudden bounding leaps in high arcs. This behaviour is called ‘pronking’ or ‘stotting’ and it makes it more difficult for the gazelle to be brought down by their predator.

When a gazelle spots a stalking predator, it will pronk or stott to alert other gazelles to the danger and can also startle their predator. Another possibility for this behaviour is that it demonstrates their fitness in hope that the predator will give up the chase or that the predator should not bother trying to chase the obviously agile gazelle.

Thomson’s Gazelles are social animals and live in herds of over 200 individuals. Thomson’s Gazelles sometimes congregate with other hoofed animals such as zebra and other species of antelope. During migration, thousands of gazelles will travel together in search of water during the dry season. Their territories may overlap with other species of ungulates with no problems. However, some may be more territorial and defend their territories vigorously if challenged. The defending male will clash horns with his opponent, the winner then claims the territory.

Thomson’s Gazelles mark the boundaries of their territory with a small secretion from scent glands located beneath their eyes. They deposit the secretion onto a blade of grass around 20 feet apart daily.

Thomson’s gazelle Reproduction

Female gazelles usually give birth after the rainy season to a single young, known as a Fawn, after a gestation period of 5 – 6 months. After giving birth, for the first 3 weeks the mother hides the fawn in tall grass and returns twice daily to nurse it until it is old enough to join the herd.

Fawns have a tawny colouring which helps them stay camouflaged when hiding in open country. They can also stay very still for long periods of time. Although adult gazelles can out run a lion or cheetah, almost half of all fawns will be lost to predators before reaching adulthood. Female Thomson’s Gazelles can give birth twice a year which is unusual for ungulates. The life span of a Thomson’s gazelle is 10 – 15 years in the wild.

Thomson’s gazelles Life Span and Predators

In the wild, Thomson’s gazelles can live 10–15 years. Their major predators are cheetahs, which are able to attain higher speeds, but gazelles can outlast them in long chases and are able to make turns more speedily. This small antelope-gazelle can run extremely fast, from 80 km/h (50 mph), to 96 km/h (60 mph) and zigzag, a peculiarity which often saves it from predators. Sometimes, they are also chased by leopards, lions, and hyenas, but the gazelles are faster and more agile; these predators attack especially the young or infirm individuals. They can also be prey to crocodiles and pythons, and their fawns are sometimes the prey of eagles, african wild dogs, jackals, and baboons. A noticeable behaviour of Thomson’s gazelles is their bounding leap, known as stotting or pronking, used to startle predators and display strength.

Conservation Status

Although numbers in some areas of Africa have declined due to hunting and habitat loss, the Thomson’s gazelle is not threatened and is classed as ‘Least Concern’ by the IUCN.

The population estimate is around 550,000. The population had declined 60% from 1978 to 2005. Threats to Thomson’s gazelles are tourist impacts, habitat modification, fire management, and road development. Surveys have reported steep declines (60-70%) over periods of about 20 years dating from the late 1970s in several places, including the main strongholds for the species: Serengeti, Masai Mara, and Ngorongoro.