Anti-snake behaviour in a facultative cooperative breeder, the Cape ground squirrel

Abstract

Predator harassment is an anti-predator behaviour that may increase an individual’s risk of predation, as individuals approach, threaten and harass a potential predator, yet this behaviour is still not well understood. The Cape ground squirrel (Xerus inauris) is a highly social facultative cooperative breeder from southern Africa that harasses several species of venomous snakes. We examined whether harassment was part of alloparental care by comparing harassment behaviours among different age and sex classes in Cape ground squirrel social groups. We also assessed how individuals adjusted their behaviour dependent on levels of risk by examining the Cape ground squirrel’s harassment behaviour among non-venomous, and two species of venomous snakes. We found adult females with emerged juvenile offspring took the most risk, harassing for longer durations and at higher intensities than other group members, suggesting that snake harassment was a maternal behaviour. Females with juvenile offspring only harassed the highest risk elapid snake but increased vigilance and inspection with increasing snake risk suggesting that the Cape ground squirrel can discriminate between different types of snake predators.