Mountain Zebra

The mountain zebra, scientifically known as Equus zebra, is a fascinating creature that graces the mountainous terrains of Sub-Saharan Africa. Like their plain-dwelling cousins, they are conspicuously striped; however, their bands are characteristically more compact.

Apart from their unbarred belly, they also have a characteristic ‘dewlap’ hanging under their lower jaws. Their robust body and sturdy build helps them navigate the rugged terrains.

Subspecies

There are two known subspecies of the mountain zebra.

1. Cape mountain zebra (E. z. zebra)
2. Hartmann’s mountain zebra (E. z. hartmannae)

Description

Length: Body – 2.1 to 2.6 m (6 ft 11 inches to 8 ft 6 inches) Tail – 40 to 55 cm (16 to 22 inches)

Weight: 204 to 372 kg (450 to 820 lbs)

Body and coloration:

As with all zebra species, mountain zebras have black or dark brown stripes, but they are closely placed around the neck and torso and are absent from the belly. The dorsal stripe along the body forms a distinctive ‘gridiron’ pattern extending to the whisk near the tip. This dewlap is more pronounced in males and in Hartman’s Zebras.

However, the ground color differs in their subspecies. In the Cape Mountain Zebras, it is white, while in Hartmann’s Zebras’ the color is buff. Cape Mountain Zebras exhibit sexual dimorphism, characterized by larger females, whereas this distinction is not observed among the other subspecies.

Distribution

They are predominant in the deserts and semi-deserts of Africa. Specifically, the Cape Mountain Zebras are native inhabitants of the western and eastern Cape provinces of South Africa, while Hartmann’s Mountain Zebras are scattered throughout Namibia, Angola, and South Africa.

Habitat

Their name suggests that they reside in the slopes and plateaus of the mountainous regions of Sub-Saharan Africa.

• Cape mountain zebras stay at elevations of around 2000 meters but move to lower altitudes during winter. Since South Africa experiences regular precipitation trends and has a relatively constant food supply throughout the year, this subspecies does not have to shift habitats for survival.
• Hartmann’s mountain zebras live in a rocky transition zone at the edge of the Namib desert, where they often face patchy water supplies and thus have to migrate to sand flats for their livelihood.

Diet

They are herbivores that fundamentally nibble on grass but can also feed on twigs, leaves, buds, and natural products when required. The primary variety of grass consumed is the Themeda triandra. During summer, they additionally use mineral licks to obtain essential nutrients.

Behavior

• Mountain Zebras lead a diurnal lifestyle, grazing and resting from dawn to dusk.
• Though gregarious, they avoid forming large groups and prefer living in small breeding herds and bachelor groups.
• They maintain a social hierarchy where a dominant stallion leads each breeding herd with up to five mature mares. In newly established packs, the stallion tries to defend the territory and prevent the mares and foals from leaving. The bachelor males live in separate bachelor groups and put efforts into capturing young mares and establishing their own harems.
• The dominant stallion makes a variety of vocalizations, including high-pitched alarm calls or snorts to alert its herd members when a bachelor male tries to uproot him. When encountered by the herd stallion, the bachelor male produces long squeals. Some ferocious fighting, kicking, and biting are involved in the subsequent confrontation.
• The zebras mutually groom themselves by rubbing, nibbling, and scratching their bodies, an action significant in maintaining group cohesion. Most individuals also take a dust bath daily. Mutual grooming most commonly takes place between mares and their foals.
• Hartmann’s mountain zebras have a characteristically playful demeanor and often engage in challenge games like chasing, racing, and play-fighting.

Lifespan

In the wild, they can survive for 20 years or more. A Hartmann’s mountain zebra that was 29 years and six months old is the oldest known Mountain zebra kept in captivity.

Reproduction and Life Cycle

Mountain Zebras have a polygynous mating system in which a single dominant stallion mates with multiple mares in the breeding herd. Their breeding season lasts throughout the year, with the highest natality reported around December and January in Cape Mountain Zebras and around November to April in Hartmann’s Zebras.

The gestation period of both subspecies is about a year, and one foal is born at the end of each breeding season. Foals weigh about 25 kg at birth and have a total body length of 120 cm. Though the young are born well-developed, they remain close to their mothers for the next few weeks for protection from any imminent danger. 

The duration of lactation varies, with mares usually nursing their foals in phases of 1.5 to 2 minutes. For the first three months, the foals are nursed hourly during the day, after which the frequency of suckling gradually decreases. The weaning time depends upon the impending arrival of siblings but usually occurs in summer when the foals are about 13 to 37 months old. 

Predators

Lions, leopards, cheetahs, spotted hyenas, and African hunting dogs are some of their natural predators. Humans also hunt them for skin.

Adaptations

Cape Mountain Zebras are adapted for life on rugged terrain with their sturdy and faster-growing hooves. The striped pattern of Mountain Zebras helps them camouflage against the rugged terrain, and they appear indistinct to blood-sucking vectors like ticks and bot-flies (Klingel, 1990).

Hartmann’s Mountain Zebras have very hard and pointed hooves that make them expert climbers.

Conservation Status

This species belongs to the ‘Vulnerable’ category of the IUCN Red List of Endangered Species. Additionally, both subspecies are listed in CITES Appendix II.

Despite declining to 100 individuals in the 1930s, Cape Mountain zebra populations increased to 1200 by 1998, only after religious conservation efforts.

According to the IUCN Red Data List (2019), the global population size of Hartmann’s Mountain Zebra is about 33,265, while that of Cape Mountain Zebra is 1,714, leading to an aggregate of 34,979 mature Mountain Zebra.