Mobbing by Florida scrub jays: behaviour, sexual asymmetry, role of helpers and ontogeny

摘要: Abstract Behavioural patterns used in mobbing predators by the cooperatively breeding Florida scrub jay, Aphelocoma c. coerulescens , are described from films, field observations and experiments. The roles of individual group members ontogeny fledglings were investigated experimentally releasing a 1·6-m snake presence jays. Jays at least nine action one variable vocalization mobbing. Male breeders mobbed most intensely, female helpers with lesser approximately equal intensity, least. Fledglings began 47 days post-hatch gradually acquired adult-like behaviour 3 months age. Coordinated flying ability may be necessary before begin to mob. Mobbing often ignored adults that had not yet seen predator. A comparison jay other congeners indicates several aspects related social system birds.