Gerenuk

The gerenuk, or the giraffe gazelle or the Waller’s gazelle, is one of the most recognizable antelopes in Africa because of its customary long neck and legs and lyre-like curved horns only seen in males. First described by naturalist Victor Brooke in 1879, its name comes from garanuug, which means “giraffe-necked” in Somali.

Description

Height: Male: 35–41.5 in (89–105 cm); Female: 31–39 in (80–100 cm)

Weight: Male: 68-115 lb (31-52 kg); Female: 62–99 lb (28–45 kg)

Face: The gerenuk has a small head, with tufts of fur running from its ears to eyes, also surrounding its mouth.

Tail: It is very prominent, 10–14 in (25–35 cm) length, ending in a black tuft.

Body and Coloration: They can be discerned quickly by their long neck and legs. Their coats are smooth and glossy, made up of short hair.

These antelopes exhibit sexual dimorphism. The males have a robust build and muscular necks, alongside big, curved horns (10-17.5 inches) that are absent in females.

They have a buff or yellowish-beige dorsal region, distinguished by a reddish-brown back. The ventral part, particularly the areas around their tail, eye rings, lips, and throat patch, appear white, and the underbelly and legs are cream. Female gerenuks have a dark patch on their crown.

Range and Distribution

This species’ domain covers the eastern part of Africa, known as the Horn of Africa. It includes the Serengeti plain of north-eastern Tanzania, southern Djibouti, Kenya, Ethiopia, Eritrea, and southern Somalia.

Habitat

It can survive in most environments containing succulent plants, preferring places with moderately woody foliage like dry flat thornbushes and thickets, avoiding either dense vegetation or very open habitats.

Diet

Unlike most other antelopes, gerenuks are browsers and foragers, feeding on plants and not grass. This is because they stand on their hind legs to eat, getting access to plants that would generally be out-of-reach.  Their diet includes tender leaves of prickly flora and trees, shoots, herbs, flowers, and fruits. They do not drink freestanding water, as they get all the moisture they need from succulent plants.

Lifespan

They live for 8-10 years, with females surviving longer than males.

Behavior

• The gerenuk is diurnal, i.e., it is active throughout the day. However, at noon, they will often rest in the shade.
• They live in small groups of up to 10 members consisting of either females or juvenile males, though young males will stay with adult females in some cases.

• Adult males are solitary and aggressively territorial, marking their territories with secretions and driving out others who enter their areas.
• Sometimes the gerenuk could be seen standing in the rain, perhaps to cool its body.
• It utilizes a wide range of vocal communications, including buzzing when alarmed, whistling to show annoyance, and bleating loudly to signify danger.The females bleat softly to communicate with their young.

Predators

Most of Africa’s big cats like lions, leopards, and cheetahs, as well as cape hunting dogs, hyenas, servals, honey badgers, caracals, and eagles, pose a threat to these antelopes.

Adaptations

• Their long neck helps them access out-of-reach foliage and increases their standing height to over 6 ft (2m).
• With the help of their impressive hind legs and specially modified vertebrae, they can stand upright for long periods. This lets them use their forefeet to tug at upper branches.
• Not being very fast, they rely on their coloring that camouflages well with their surroundings, helping theem seek shelter from predators in thick bushes.
• The large horns on the males help them to fight off other males.  
• The gerenuk has a pointed snout and a long upper lip and tongue, which allows them to access difficult-to-reach foliage.

Mating and Reproduction

They are polygynous, having a complex mating ritual. If the female responds positively while encountering a potential mate, the male will mark her thighs with the secretions from the pre-orbital glands found in their eyes. He will then follow her around until she is ready to mate.

They breed year-round, sometimes preferring the rainy season.

Life Cycle

The gestation period of the fawn is 6-7 months. After being weaned for 12-18 months, the babies become independent. They reach sexual maturity at around 1-2 years.

Conservation Status

The IUCN lists the gerenuk as “NT” or “Near Threatened”. Its population appears to be decreasing due to activities like hunting as game and other human interference.

Interesting Facts

• The mother is highly cautious of her fawn’s security, keeping it hidden in the bush and even cleaning or eating up its waste so that the predators cannot trace them.  
• They have surprisingly benefitted from the clearing of land for livestock as this has allowed more thornbush to grow for their consumption.