Aerial jousting and bill grappling in Indian Grey Hornbill (Ocyceros birostris)

The hornbills in the family Bucerotidae have two interesting, little-studied behaviors-aerial jousting and bill grappling. The number of observations of these interactions is few and interpretations vary greatly. The few observations, always reported as singular events, have been interpreted either as aggression, social interaction, pair bonding, or play. Following our study of the Indian Grey Hornbill (Ocyceros birostris), we suggest that the bill grappling and aerial jousting may best be explained in two different contexts of the life cycle-social play in the non-breeders and as a courtship ritual in the adult, breeding birds.