Gemsbok

The gemsbok is the largest and best known of the four species of oryx, or straight-horned antelope. It is one of the best desert-adapted large mammals, capable of surviving in waterless wastelands where many animals would perish. It is second only to the addax in this regard.

Its metabolism is superbly adapted to conserve moisture. When subjected to hot weather, the gemsbok’s body temperature rises and after three or four hours of exposure it loses excess heat by radiation. In addition, its kidneys are capable of handling very brackish water.

The gemsbok has mechanisms to ensure that the temperature of the blood circulating to the brain can stay below that of the body temperature. When deprived of water, it doesn’t sweat, thus saving it from dehydrating.

The gemsbok doesn’t lose water due to a lack of evaporative cooling. Its urine is highly concentrated and feces are almost dry, so that water loss is minimal in that regard.

The gemsbok often grazes at night when plants have higher moisture content. It is usually inactive for most of the day. Gemsbok are highly nomadic in the desert, but where there are watering holes or a good supply of water-bearing vegetation, herds may remain year-round in smaller home ranges, within which bulls defend territories.

Newly born gemsbok hide themselves after birth, sometimes with encouragement from the mother in the form of a threatening butt. There the calf lies curled up and waits for the mother to come back to nurse it. The mother usually walks around the area in which the calf is concealed and calls it out.

The calf may then spend the night with the mother before being taken to its next hiding place – often as much as 1.5 miles from the previous one. Females with newborn calves are very wary and will not approach the hiding places if they are aware of the presence of observers.

After a period of about six weeks, the mother and the calf join the herd. Nursing of calves within a herd appears to be synchronized, as all the young suckle within a period of 5-10 minutes.

A young gemsbok’s horns grow extremely fast during the concealment period, and therefore it is easy to understand the myth that a gemsbok is born with horns. Females can mate again a few weeks after calving.