Vigilance and group size in springbok

Abstract

Wild springbok Antidorcos marsupalis, in the Ethosha National Park, were observed while feeding in groups of varying size, and the numbers of vigilant (neck erect, head up) animals recorded. The proportion of vigilant springbok declined as group size increased. However, an individual's feeding time apparently does not increase and may even decline in groups larger than about 25 animals. These findings are discussed In relation to anti-predator and other benefits resulting from grouping.