Function of meerkats' mobbing-like response to secondary predator cues: recruitment not teaching

Abstract

Early detection of predators greatly improves prey escape and survival chances. By investigating cues predators leave behind, such as fur, urine, faeces or feathers (secondary predator cues), prey may gain vital information about predators in the vicinity. Meerkats, Suricata suricatta , display an unusual mobbing-like response upon encountering secondary predator cues, not reported in any other species. The function of this behaviour is unclear because, unlike mobbing of a live predator, it cannot yield the primary benefit of driving the threat away. Here we examine two potential functions. First, we hypothesized that older group members may exhibit exaggerated mobbing-like responses towards secondary predator cues as a form of teaching to promote learning in naïve pups. Meerkats are known to teach pups hunting skills, but there is no evidence that any nonhuman species teaches across multiple contexts. Mobbing-like responses could also function to facilitate group member recruitment, stimulating information gathering and collective decision making by the group. Using experimental presentations of secondary predator cues in the presence and absence of pups, in combination with 20 years of data on natural encounters with secondary predator cues, we found that older group members' response frequency was lower when pups were present and that response intensity declined as the proportion of pups to total group member number increased. Conversely, the intensity of responses increased when a greater proportion of group members interacted with the cue and varied with predator cue type. The response frequency to natural encounters with secondary predator cues was greater in larger groups, and the distance travelled by the group decreased following an encounter with secondary predator cues. These results suggest that meerkats do not show exaggerated responses to secondary predator cues as a form of teaching. Mobbing-like responses more likely serve to increase recruitment of others to investigate the cue and inform defensive group behaviour. • Meerkats show an unusual mobbing-like response to secondary predator cues (SPCs). • We examined potential functions using cue presentations and long-term observations. • No evidence to support teaching via increased mobbing-like response in pup presence. • Large groups responded to SPCs more often; distance travelled fell after encounters. • Mobbing-like response facilitates recruitment and informs group defensive behaviour.