Although white rhino females can reach sexual maturity around the age of five, in the wild, neither sex will reproduce until they are “socially mature”. In the case of females, they will have their first calf when they are six and a half or seven years old. In the case of males, they will probably not breed until they establish their own territory, which could be around the age of 12 (although recent studies suggest some males sire offspring even before establishing a territory).
Until a male white rhino establishes his own territory, he is a beta male. Beta males are allowed to stay at other males’ territory as long as they behave subordinately to the territorial male. Territorial males are also called alpha males.
As subordinates, beta males will not scatter their dung when defecating at a midden (also called dung heaps), as that behaviour only corresponds to the alpha male. White rhinos defecate at middens, which are large piles of dung where different rhinos defecate. Middens play a role in social communication, as the odours of different animals are found in a small area. It is believed that by kicking the dung and scattering it over the midden and beyond, the alpha male spreads his odour acting as a signal of who is the territory owner in the area. Beta males will also not attempt to mate with the females in that territory, and will behave in a “not challenging” way (although standing his ground) when encountering the resident male.
Male territorial behaviour is one of the topics of our orphan rhino rehabilitation and release program. Rehabilitated rhinos are monitored one year after release to determine, amongst other questions, whether male rhinos are able to establish their own territories. However, it is crucial that before they achieve the alpha bull status, they know how to behave subordinately to territorial bulls, as a fight between adult males can be fatal. In other words, rehabilitated rhinos must know the “social rules” of their species and behave accordingly if they are to establish sustainable wild populations that contribute to the conservation of their kind.