Anti-predator strategies of immature Thomson's gazelles: hiding and the prone response

Abstract

The use of hiding and the prone response as anti-predator strategies by immature Thomson's gazelles, Gazella thomsoni, was investigated. Hiding, a behaviour restricted almost entirely to fawns, decreased the probability that infants would be found by cheetahs, Acinonyx jubatus, at a time when their ability to outrun predators was poor. The period of transition from hiding to active appeared to be a time of high mortality; although no increase in the ability of fawns to outrun predators with age could be detected, older fawns still spent more time out of hiding, increasing the probability that they would be spotted by predators. Once chased, dropping down out of sight and adopting the prone response was associated with a decreased probability of capture. Fawns that dropped down further from approaching cheetahs were less likely to be found than those that dropped down when the predator was closer. Since fawns that dropped down had mothers that detected approaching predators further away and more vigilant mothers detected approaching cheetahs at greater distances, increased maternal vigilance had a direct payoff in terms of increased infant survivorship.