Vigilance Behaviour in African Ungulates: The Role of Predation Pressure

摘要: Impala Aepyceros melampus and wildebeest Connochaetes taurinus vigilance behaviour was concurrently monitored in two adjacent sites where re-introduction of large felids at one site gave rise to increased predation pressure. In the high site, rate looking proportion time spent by both species significantly greater than low site. Vigilance also showed an increase over following feIid re-introduction: there no re-introduced feIids were absent. The relationship between herd size, position presence juveniles compared for conditions. Herd size a negative correlation regardless Mothers with always most vigilant members central animals least watchful interplay pressure, is discussed. It suggested that pressure principal influence on ungulates even very risk appears contribute vigilance. Impalas spared devoted little vigilance, suggesting it played minor role intraspecific interactions finding food.