Are domestic chickens born with predator recognition? Validation of a sound playback experiment.

Predation risk can influence behavioral decisions of animals in various ways. Prey animals have the opportunity to choose antipredation behaviors and escape strategies only by quickly and accurately identifying predators. As precocial birds, domestic chickens (Gallus gallus domesticus) have no adaptation period after hatching and must immediately survive under predation risk. They possess a strong ability to identify threats through vocalizations. To explore whether domestic chickens have innate predator recognition ability and whether the antipredation behavior of breeding chickens is stronger than that of non-breeding chickens. We tested the antipredation behaviors of three types of flocks (non-breeding chickens; hen with chicks; isolated chicks) of domestic chickens in response to sparrowhawk (Accipiter nisus) calls using playback experiments, while Oriental turtle dove (Streptopelia orientalis) calls were used as a control. We found that breeding hens are significantly more vigilant than non-breeding chickens. We also found that although isolated chicks can exhibit antipredator behavior, they cannot accurately identify the calls of predators and non-predators. Therefore, it can be concluded that domestic chickens exhibit varying degrees of vigilance towards predator calls at different stages of their life history. Reproductive costs can lead to increased vigilance in domestic chickens. The accurate identification of predators by domestic chickens is not innate, but gradually formed over time.