Nanger granti
Grant's gazelle

Nanger granti is found only in eastern Africa, where they range up to 2,000 meters in altitude. ()

Grant’s gazelles migrate seasonally over a large part of their range preferring higher, well-drained areas during the rainy season, and moving to lower, grassy valleys during the dry season. They are not dependent on water and, consequently, they migrate in the opposite direction of water-dependent species such as Thomson’s gazelles, wildebeest, zebras, and topi. In doing so, Grant’s gazelles avoid competition and are able to survive on vegetation found in this semi-desert environment. However, N. granti remain throughout the year in areas where there is a plentiful supply of food. ()

Grant’s gazelle habitat consists of semi-desert, open savannas, and treeless plains. They avoid acacia forests unless they are traversed by well-traveled paths. ()

Grant's gazelles are large, pale gazelles with long horns and legs. They have a distinct rectangular, white shape on the hindquarters and a contrasting black stripe running down the thigh. Thomson’s gazelles (Eudorcas thomsonii), a closely related species, have some similar physical characteristics. They both possess white coloring on the hindquarters, but Grant’s gazelles have more white than Thompson’s gazelles. Nanger granti is paler and has bigger horns than Thompson's gazelles. ()

Males and females are dimorphic. Males are larger than females, and they have longer, thicker horns, ranging from 50 to 80 cm. The horns are ringed. In contrast to males, females have smaller horns (30 to 40 cm) that are thin and symmetrical. ()

The young are more darkly colored than adults. ()

Grant's gazelles have an average lifespan of around 12 years. ()

Grant’s gazelles are migratory and they move seasonally throughout their range, except in areas with year-round supplies of forage. They migrate in groups and some groups establish home ranges. Herds may segregate into separate groups of bachelor males and females with dominant males. Social rank in this species can be seen in the way males are organized when migrating. The less dominant, younger males are towards the front of the unit, whereas the more dominant males are in the back. This organization also results in equally matched opponents in fights, as it is more likely that nearby males will display dominance and fight one another. ()

Territorial males mark areas with a combination of feces and urine. This type of marking requires the gazelle to advertise his white rump. As a result of this advertisement, other N. granti either show interest or withdraw. ()

One way in which N. granti show dominance is through side-by-side strutting. In strutting alongside other territorial males a male may express his dominance by raising his neck and tilting his horns slightly. A second method by which Grant’s gazelles show dominance is through fighting. When two males approach each other to fight, they quickly move their heads downwards and towards one another as one tries to throw the other off balance. Fighting displays the contender’s neck muscles. ()

As a form of anti-predatory behavior, N. granti use alert posture, alarm snorts and stamping as signals of a predator in the vicinity. They avoid water holes, where predators are plentiful and prey are vulnerable. Females may resist when a fawn is captured by a predator, cooperating with other females to fiercely defend the abducted fawn. This defense often chases the predator away, leaving the fawn unharmed. ()

Nanger granti, along with many other ungulates, display an anti-parasitic behavior of selective defecation. Grant’s gazelles defecate in specific locations in order to keep the parasites associated with dung piles away from other members of the herd. Additionally, N. granti avoid foraging in locations where selective defecation has taken place. ()

Home Range

Throughout the year, N. granti range in an area of about 290 square km. ()

Grant's gazelles communicate through territorial markings made with urine and feces, sex pheromones, and visual displays. They communicate the presence of a predator by alert posture, alarm snorts, and stamping. ()

The dark coloration around the female’s anus serves as source of visual attraction between a fawn and its mother.

Nanger granti are primarily browsers, rather than grazers. A large part of their diet consists of leaves and stems. ()

Since N. granti live in an arid environment, water conservation and consumption is important for survival. While Thomson’s gazelles uses evaporative cooling as a method of decreasing body temperature, Grant's gazelles allow their body temperature to rise with air temperature, dissipating body heat to the surrounding air when temperatures fall. At night they may also eat leaves, which contain more water during the cooler, nighttime hours. ()

While many predators are threats to N. granti, cheetahs (Acinonyx jubatus), wild dogs (Lycaon pictus), and golden jackals (Canis aureus) are particularly fond of N. granti fawns. During the rainy season, when the ground is soft, cheetahs (Acinonyx jubatus) take advantage of the greatly reduced speed of these gazelles. ()

Nanger granti uses anti-predatory signals including alert posture and alert snorts. They avoid areas with a high density of predators and employ cooperative defense to protect vulnerable fawns. ()

Grant’s gazelles are prey for cheetahs (Acinonyx jubatus), wild dogs (Lycaon pictus), and golden jackals (Canis aureus). They are also important herbivores in the habitats in which they live. ()

Nanger granti inadvertently affects the population density of pouched mice (Saccostomus mearnsi) in eastern Africa by depleting the supply of food for these rodents. In areas where Grant’s gazelles are less common, S. mearnsi populations flourish. ()

There seems to be no negative impacts caused by N. granti.

The inadvertent control of the pouched mice (Saccostomus campestris) populations by N. granti is advantageous to humans. In addition to being agricultural pests, pouched mice may spread disease. Grant's gazelles are sometimes hunted for meat and trophies and they are sought by ecotourists. ()

According to the IUCN, a threat to N. granti is human habitat destruction. Habitat loss is leading to population decreases of Grant's gazelles.

A Ugandan tribe uses Grant’s gazelles as one of their four major totems. They are also respected as animals possessing great beauty. ()