A Ugandan tribe uses Grant’s gazelles as one of their four major totems. They are also respected as animals possessing great beauty.
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.
Communication Channels: visual ; tactile ; acoustic ; chemical
Other Communication Modes: pheromones ; scent marks
Perception Channels: visual ; tactile ; acoustic ; chemical
According to the IUCN, a threat to N. granti is human habitat destruction. Habitat loss is leading to population decreases of Grant's gazelles.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
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.
Positive Impacts: food ; body parts are source of valuable material; ecotourism ; controls pest population
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.
Ecosystem Impact: disperses seeds; creates habitat
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.
Plant Foods: leaves; wood, bark, or stems
Primary Diet: herbivore (Folivore )
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.
Biogeographic Regions: ethiopian (Native )
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.
Range elevation: 2500 (high) m.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: desert or dune ; savanna or grassland
Grant's gazelles have an average lifespan of around 12 years.
Average lifespan
Status: wild: 12 years.
Average lifespan
Status: wild: 12 years.
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.
Range mass: 45 to 65 kg.
Range length: 140 to 166 cm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger; ornamentation
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.
Known Predators:
When a female gazelle is in estrus, her urine contains sex pheromones indicating her reproductive status to males. In order to detect these, males perform flehmen behavior. Males curl their lips and suck air into their vomeronasal organs to detect whether sex pheromones are present. This behavior is done by N. granti as well as G. thomsonii.
If pheromones are detected, the male actively pursues the female. Courting takes place, in which the male prances with his head held high and his tail held horizontally. This eventually leads to copulation. However, if no sex pheromones are detected, the male does not further pursue the female.
Mating System: polygynous
Grant's gazelles reach sexual maturity at three years of age for males and about one and half years for females. Timing of the mating season depends on location. For example, in southern Kenya and Tanzania, mating takes place throughout the year. In the Serengeti, mating takes place in all months except June, July, October, and November. The gestation period is about 27 weeks.
Breeding interval: Females typically give birth once per year.
Breeding season: Gran't gazelles can breed throughout the year but local climate affects the timing of reproduction.
Range number of offspring: 1 (low) .
Average number of offspring: 1.
Range gestation period: 6 to 6.63 months.
Average gestation period: 6.3 months.
Average weaning age: 6 months.
Average time to independence: 1.5 years.
Average age at sexual or reproductive maturity (female): 1.5 years.
Average age at sexual or reproductive maturity (male): 3 years.
Key Reproductive Features: seasonal breeding ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; induced ovulation ; viviparous
After birth, the fawn is completely cleaned of any fluids by the mother. The fawn then drinks its first meal of milk and seeks protection near its mother. If the mother is going out to graze, the fawn remains in a secure hiding place which is observable to the mother from where she is grazing. The mother-fawn relationship is the only persistent relationship in N. granti.
Parental Investment: altricial ; female parental care ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female); post-independence association with parents
