The tsessebe is a large antelope, with a shoulder height of some 1.2 m. They measure between 150 to 230 cm in length; with males being slightly larger than females. Both sexes grow horns, which are between 30 and 40 cm long. Females usually have slightly shorter horns, while those of the male are generally between 37 and 40 cm.
Although this antelope only weighs between 10 and 12 kg at birth, the common tsessebe grows to a fairly sturdy specimen. Bulls weigh around 135 to 140 kg and cows reach an average weight of about 120 kg.
These grazers opt for open savannahs, grasslands, plains and lightly wooded areas. Occasionally, they can also be found in rolling hills or on flats that are less than 1 500 metres above sea level.
Tsessebe are common in South Africa, as well as in countries slightly further north – including Angola, Botswana, Namibia, Swaziland, Zambia and Zimbabwe. In South Africa, the Kruger National Park is one of the best places to spot them.
Diet - Herbivores
The common tsessebe is a grazer, and feeds on the juicy grasses and leaves of its natural habitat. They prefer fresh growth and can, therefore, often be found in areas that have been burnt and are experiencing a period of renewal. It usually feeds out of the heat of the day, taking a break between about 09h00 and 16h00. They need clean, fresh water, and will travel for up to 5 km a day to a good water source.
Tsessebes are gregarious, sociable animals that enjoy being part of a herd. However, males and females form their own separate herds. Young males join a bachelor herd, which can comprise of some 30 individuals. More mature bulls will be part of another herd, also of a few dozen bulls, but not including the bachelors. Females will form a herd of between 6 and 10 cows, as well as their calves. These are territorial antelope, and have a variety of ways to establish their dominance and their territory. These techniques include parading in front of the cows with their noses high in the air, ground horning (striking at the ground with their horns), swiping one another with shoulders, grunting, defecating in a crouch stance, high-stepping and mud-packing (throwing mud at other males using the horns). Other than this, there are not particularly aggressive encounters.
Another territorial tactic that they use is the bathing of their foreheads and horns in an oily secretion that comes out of a gland near their eyes. To get this secretion from the gland to their horns and face, they insert a grassy stem into the preorbital glands, coating it in the oil. Then, they wave the grassy stems around, which causes the oil to fall onto their foreheads and horns.
Other behaviour that continues to befuddle researchers (in terms of their purpose) includes their ability to sleep with their mouth flat on the ground and their horns sticking straight up into the air, and the males’ tendency to stand in parallel lines and bob their heads backwards and forwards with closed eyes.
Males go through a season during which they will compete for females, known as a rut. This usually lasts from the middle of February to March, which coincides with the oestrus cycle of the cows. The bulls form a lek (a congregation) in the area in which the females will come looking for a mate.
The lek provides added protection from predators (due to the increased numbers of strong males) and gives the females more variety from which to choose. The dominant males stay in the centre of the lek, giving the cows an indication of who can provide stronger genes. To get to the centre, they have to compete with the other males, establishing their strength and dominance. During her day (or a little longer) of oestrus, she will mate many times to ensure insemination.
After mating, the female is pregnant for 7 to 8 months, after which one calf is born. She can continue to produce one calf every year. They give birth around September or October. The calves are part of the cow’s herd. Young bulls will leave and become part of a bachelor herd when they reach sexual maturity (at around 2 years of age).
The cow carries her unborn calf for between 7 and 8 months.
The common tsessebe can live for about 15 years in the wild.
The population numbers of the tsessebe used to be very healthy, but there has been a sharp decline in the last century as a result of habitat destruction and bush encroachment, as well as hunting for meat. In some areas, they are killed by farmers who want the grazing space for their cattle. This leaves human beings as its primary threat. However, young and weak antelope may also fall prey to hyenas, lions and other predators.