The role of companionship in the dispersal of white rhinoceroses (Ceratotherium simum)

Dispersal is a risky process, both through social pressures and the uncertainty in finding resources. The white rhinoceros is unusual among rhinoceros species in its incipient sociality, manifested through the formation of temporary or more persistent groups involving subadults of both sexes plus adult females without small calves. We describe the probing excursions made by subadult white rhinos out of their established home ranges which were invariably made with a companion. We suggest additional benefits of companionship in such dispersal movements, besides diluting predation risk, via (1) reducing the likelihood of being attacked by territorial males and (2) familiarization with a wider region of the environment, guided by the companion. This "buddy system" may be important in reducing the high costs potentially associated with dispersal.