24/06/2025
The Mountain Nyala was the last large ungulate
to be discovered in Africa. They are found only in
Ethiopia, south of the Rift Valley.
Once widely distributed in the southeast highlands of
Ethiopia, their range and population have suffered
a dramatic decline over the last several decades due
to habitat loss as a result of agricultural expansion
and killing. There are approximately 3,700 nyala
remaining in the Bale Mountains, 30 – 40 percent of which are found in the park alone. This is the
majority of the population with only very small
pockets found in nearby mountain ranges.
Though more prominent in males, mountain nyala
have unique white spots and stripes on their sides.
Males typically weigh between 180 and 320kg,
while females weigh between 150 and 200kg.
When mature, males have a mane of erectile hairs
along the spine.
Mountain nyala are usually seen in small family
groups of females with calves. Calves can be born
throughout the year but there is a peak in births
between December and March. The calves accompany
their mothers for up to two years. At about two years
old, females conceive and after a gestation of about
nine months, they give birth to a single calf. At the
same age, juvenile males develop their secondary
sexual characteristics – horns, a dark spinal mane,
and the behavior that brings them into conflict with
adult males. They usually leave their family group
to join ‘bachelor’ groups of other males. They form
a dominance hierarchy, maintained between younger
males by tussles and in the older males by ritualized,
strutting displays. When displaying, their perceived
size increases with their erectile hairs. The displays
can end in a fierce, brief clash of horns if neither
male backs down. With age, male nyala become
solitary.
The species has a wide ecological zone that ranges
from 1,800m to 3,750m. Size, colour and feeding
habits vary slightly with altitudinal difference.
Females are mainly grazers when grass is available
in the wet season and become browsers in the dry
season. Males are mostly browsers throughout
the year. Their main foods are St. John’s wort,
African or wild wormwood (Artemesia afra),
Gallium semensis, Hagenia abyssinica, Cape
Gold (Helichrysum splendidum), Discopodium
spp. and Thistle (Carduus spp). Because grass is
not available in the dry season, the mountain nyala
move to the woodland regardless of altitudinal
difference, in search of food. They rely on the
woodland for sustenance, and it is therefore critical
for the mountain nyala’s survival.
