Grant's Gazelle

Nanger granti

Description

The Grant’s gazelle is a large, pale-colored gazelle with long horns and legs. The hindquarters have a distinct rectangular white patch of fur that contrasts against a black stripe down the thigh. Males are typically larger than females with longer, thicker, ringed horns (50-80 cm). Females have smaller (30-40 cm), thin horns that are symmetrical.

Habitat

Grant’s gazelle can only be found in eastern Africa up to 2,000 m in altitude, preferring higher, well-drained areas during the rainy season and migrating to lower, grassy valleys during the dry season. This gazelle lives in semi-desert, open savannas, and treeless plains. Grant’s gazelles tend to avoid acacia forests.

Feeding Behavior and Diet

This species is mostly a browser, rather than a grazer. Much of the diet consists of leaves and stems. The Grant’s gazelle can survive on semi-desert vegetation. This species is not dependent on water and migrate in the opposite direction of water dependent species, reducing competition for vegetation.

Reproduction 

Mating season varies based on location; in southern Kenya and Tanzania, mating occurs throughout the year, while mating does not occur in June, July, October and November in the Serengeti.  During mating season, males perform a “flehmen” behavior to tell if a female is in estrus. This behavior involves curling the lips and sucking air into their voneronasal organs to detect if sex pheromones are present in the urine of a female. If pheromones are detected, the male courts the female by prancing with his head held high and tail held horizontally. Fawns are born 27 weeks after mating. Young have darker colored fur than the adults. Male Grant’s gazelles reach sexual maturity after 3 years while females reach sexual maturity after 1.5 years.

Months and Times of Activity

Grant’s gazelle herds migrate seasonally to higher, well-drained areas in the rainy season and lower, grassy valleys in the dry season. They are capable of migrating to areas where other migrating ungulates cannot because the Grant’s gazelle is not dependent on a water source. These gazelles may choose not to migrate if food is abundant in their area. During migration, social rank determines herd organization. Dominance is determined by fighting of the males, these fights are initiated by advertising their white rump. If the opponent does not withdraw from the initiation, the ales strut side-by-side, necks raised and horns tilted. During a fight, the males approach each other and try to throw the opponent off balance. Less dominant, younger males are located in the front of the herd while more dominant males are in the back.

Special Features, Stories, Relationships

•    The Thomson’s gazelle and Grant’s gazelle are closely related and look very similar, but the Grant’s gazelle has more white than the Thomson’s gazelle.
•    Grant’s gazelles avoid water holes because many predators gather to take advantage of vulnerable prey while drinking.
•    Grant’s gazelles defecate in specific locations to avoid parasites associated with dung piles and keep them far from the herd. They also avoid foraging where defecation has taken place.
•    If a predator takes a fawn, females will work together to fiercely defend the fawn and resist the predator.
•    To read legends featuring this animal go to; http://www.mythfolklore.net/3043mythfolklore/reading/africa/pages/11.htm
•    Children’s book featuring this animal: In The Country of Gazelles by Fritz R. Walther

References

Khankari, N. 2006. "Nanger granti" (On-line), Animal Diversity Web. Accessed November 04, 2014 at http://animaldiversity.ummz.umich.edu/accounts/Nanger_granti/