The characteristic sound of the impala rutting season can not be mistaken in the African bushveld and this ancient ritual of activity peaks during the month of May.
The busy sound of the impala males aggressively snarling, growling, roaring and snorting to establish their individual dominance resonates through the air at this time, with little respite.
Impalas are gregarious by nature, choosing to live out their lives in associated groups, called herds. Herd sizes can vary from a few individuals to as many as 100. Herds are usually made up of a grouping of bachelors or a grouping of breeding females and their young with a few adult males in attendance.
The seasonal collective oestrogen cycles of the adult females stimulate the breeding interest of the adult males. The competition between the males to determine an order of dominance and establishment of mating rights is what we observe as the annual rut. Besides all the noise and fuss from the males during the rut, the breeding herds are attracted to the valuable resources of food, water and shelter that the territorial males secure. Home ranges of breeding herds therefore overlap with a number of male territories.
Male territoriality is paramount during the rut. At this time territorial males defend their space vigorously against other intruding males, the only exception being around water points which are considered neutral territory, and so a level of tolerance is displayed at these facilities. Impalas are water dependant species, meaning that their digestive and dietary requirements are such that they need to drink water on a daily basis. In the APNR, studies show that impalas seldom move more than 2.5 kms away from water.
In terms of feeding, impalas are classified as mixed feeders, they have the ability to both browse and graze, depending on seasonal availability of food. This feeding adaptability makes them successful competitors for available resources. It ensures good fecundity and recruitment within the population.
by John Llewellyn.