Average Mass: Rowland Ward: |
Track: 54mm (2 1/8") x 32mm (1 1/4 ") |
Distribution is Northern Tanzania, southern Somalia and Coastal districts of Kenya. Horns are small, almost parallel and with very little spread. Grant's are large, pale, fawn-colored gazelles with long legs. The males are larger and heavier and their horns longer than the females. The lyre-shaped horns are stout at the base, clearly ringed and measuring from 18 to 32 inches long. The width of the spaces between the horns and the angles of growth differ among the various types of Grant's gazelles. On the females black skin surrounds the teats, with white hair on the udder. This probably helps the young recognize the source of milk. When a fawn is older and moving about with its mother, the dark stripe on the white background may serve as a beacon for it to follow. Grant's gazelles are especially fond of open grass plains, and although they frequent bushy savannas, they avoid areas of high grass. Grant's gazelles may remain in areas where food is plentiful. Mature males establish territories they may hold as long as eight months. A male tries to detain the female herds of 10 to 25 individuals as they pass through these territories while they move about to feed. At the same time males chase off rival males and try to mate with females in estrus. Grant's gazelles have developed several ritualised postures. For example, the territorial male stretches and squats in an exaggerated manner while urinating and dropping dung. This apparently warns other males to stay away and reduces the number of confrontations. Younger males will fight, but as they grow older the ritualised displays often take the place of fights. When fighting does occur, it also is ritualised It starts with "pretend" grooming, repeated scratching of the neck and forehead with a hind foot and presenting side views of the body. If neither combatant is intimidated, they may confront one another and clash horns, trying to throw the other off-balance. The gazelles vary their diet according to the season. They eat herbs, foliage from shrubs, short grasses and shoots. Grant's gazelles are not restricted to certain habitats by a dependency on water, but obtain the moisture they need from their food. Grant's have unusually large salivary glands, possibly an adaptation for secreting fluid to cope with a relatively dry diet. They typically remain in the open during the heat of the day, suggesting an efficient system to retain the necessary fluid in their bodies. Breeding is seasonal, but not firmly fixed. Gestation is approximately 7 months, and the young are born in areas that provide some cover. The newborn fawn is carefully cleaned by the mother who eats the afterbirth. Once the fawn can stand up and has been suckled, it seeks a suitable hiding place. The mother watches carefully and evidently memorizes the position before moving away to graze. She returns to the fawn three to four times during the day to suckle it and clean the area. The lying-out period is quite long-two weeks or more. The fawn eats its first solid food at about 1 month, but is nursed for 6 months. Grant's become sexually mature at about 18 months. By that time the young males will have joined an all-male bachelor herd, but it will be some time before they become territory holders, if at all. Males from the bachelor herds challenge the territorial males, but only the strongest win territories, which they mark with combined deposits of dung and urine. All the major predators kill Grant's gazelle, but cheetahs and African hunting dogs are the most prevalent. In some areas jackals prey on the young. Because of its adaptation to semi-arid and sub desert ranges as well as its good meat and valuable skin, Grant's gazelle has been one of the species that scientists consider as a potential source of protein for humans. The only relatively long-lasting relationship in gazelle society is that of a mother and her most recent offspring. Grant's are gregarious and form the usual social groupings of small herds of females with their offspring, territorial males and all-male bachelor groups. Membership in these groups is temporary.
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