Litocranius walleri inhabits the dry brushy region of east Africa from the Serengeti plain of Tanzania north along the coast through Kenya, Ethiopia, Eritrea, and into southern Somalia. The species was once found in eastern Egypt and northeastern Sudan as well.

Biogeographic Regions: ethiopian (Native )

The long neck and long, thin legs of gerenuks are their defining features; these make them one of the world's most easily recognized antelopes. The coat is of a short, fine, glossy hair that is evenly distributed over the whole body. The pelage is a pale tawny brown with white along the breast, underbelly, and inner legs. There are small, dark patches of fur on the knees of the forelegs and at the end of the tail. The head is long and narrow with medium-sized ears, and the cheek teeth and masseter muscle are reduced. On the head there is a dark patch around the eyes that pales as it goes outward until it forms a white rim. Only males of this species have head ornamentation in the form of scimitar shaped horns ranging from 25 to 44 centimeters in length. Both sexes of L. walleri are of similar size but the males are more muscular than females causing them to outweigh them. Mass ranges from 29 to 58 kg, total body length from 140 to 160 cm, and tail length from 220 to 350 mm.

Range mass: 29 to 58 kg.

Range length: 140 to 160 cm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: ornamentation

• Terrestrial

The habitat that Litocranius walleri occupies varies from the treeless plains of Tanzania in the southern reaches of its range to the dry high deserts of Kenya. They are adaptable and do well in a variety of habitats, provided there is a good supply of succulent plants.

Range elevation: 0 to 3,000 m.

Habitat Regions: tropical ; terrestrial

Terrestrial Biomes: desert or dune ; savanna or grassland

Litocranius walleri is well adapted for obtaining forage from their arid habitats. Their long necks, long legs, and the ability to stand on their hind legs allows L. walleri to obtain tree leaves that are out of reach for most other antelope species. This permits gerenuks to be selective in the foods they eat and to be efficient browsers of herbaceous plants. Over 80 different species of plants have been found in a single individuals stomach. L. walleri does not drink free standing water, they instead rely on water taken in when they eat succulent plants.

Plant Foods: leaves; seeds, grains, and nuts

Primary Diet: herbivore (Folivore )

Although rare, gerenuk contribute to nutrient cycling in the ecosystems in which they live through their foraging activity. They also act as prey species for large predators.

Several anti-predator adaptations have evolved in Litocranius walleri for their survival both while they are juveniles and as adults. Young L. walleri remain motionless while hiding in the bushes and tall grasses not far from their mothers during the day when the mother is feeding. As adults they show an adaptation that is more common to forest dwelling antelopes than to desert-adapted ones, they freeze at the aproach of danger. They are preyed on by a diverse set of large predators found throughout their range.

Known Predators:

• cheetahs (Acinonyx jubatus)
• leopards (Panthera pardus)
• lions (Panthera leo)
• cape hunting dogs (Lycaon pictus)
• hyenas (Hyaeninae)
• servals (Leptailurus serval)
• ratel (Mellivora capensis)
• caracals (Caracal caracal)
• large eagles (Accipitridae)

Communication Channels: visual ; tactile ; acoustic ; chemical

Other Communication Modes: pheromones ; scent marks

Perception Channels: visual ; acoustic

The average life span of female Litocranius walleri is slightly longer than males. Their lifespan in the wild averages 10 - 12 years.

Typical lifespan

Status: wild: 10 to 12 years.

Average lifespan

Status: captivity: 13.0 years.

The mating ritual of Litocranius walleri is complex. When a male encounters a potential mate the female will raise her nose into the air and pull her ears close to the head as a sign of defensiveness, meanwhile the male displays his horns and neck in a sideways pose. If the female is receptive then the male will mark the female on the thigh with the contents of his preorbital gland and contiue to follow her around, a form of mate guarding. As the male follows the female he continually uses his forelegs to kick the female in her thigh region. When the female atempts to urinate the male performs the flehmen test or lip curl test in which he samples her urine. Once the female comes into estrous the male will notice the difference in the females urine and mating will begin. Males will attempt to mate with as many females as they can. (Macdonald, 1984)

Mating System: polygynous

Gerenuk females breed every one to two years, depending on the sex of their previous year's offspring. Males are dependent on their mothers for longer than are females. Reproduction and births occur throughout the year and may depend on the quality of available nutrition. Females give birth to usually one young after a gestation period of about 165 days.

Breeding season: Breeding occurs throughout the year.

Range number of offspring: 1 (low) .

Average number of offspring: 1.

Range gestation period: 6.77 to 7 months.

Range weaning age: 12 to 18 months.

Range age at sexual or reproductive maturity (female): 1 to 2 years.

Range age at sexual or reproductive maturity (male): 1 to 2 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); fertilization (Internal ); viviparous

Average number of offspring: 1.

Female Litocranius walleri usually give birth to one young, rarely two. The young are precocial and begin to walk within minutes of birth. The female continues to look after her young until she weans them. Young females get weaned when they reach one year of age but male offspring are not weaned until they reach at least one and a half years old and stay with their mothers until after they are two.

Parental Investment: altricial ; female parental care ; post-independence association with parents

Litocranius walleri is a game animal, even though its not very common, and as a game animal it is protected in most of its range in the form of tags or permits. There are many parks offering sanctuary for them within their range and many biologists and game managers studying them so they are not considered to be at significant risk currently.

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: near threatened

There are no adverse effects of L. walleri on humans.

Litocranius walleri has been a game animal in Africa for over 200 years. Although they are limited in supply for hunters and have a limited range, they continue to be hunted for trophies and for bush meat. In the expanding world of photosafaries and parks in Africa L. walleri will become a regular subject for this endeavor. Unfortunately L. walleri doesn't do well in captivity and has rarely been bred in zoos.

Positive Impacts: food ; ecotourism