There are various reasons for head bobbing. It can act as a greeting between swans or swans and familiar humans. Head bobbing can be a part of the mating ritual as both swans will dip their heads before mating. Additionally, swans will dip and bob their heads while bathing in order to wash their heads as well as when feeding to access the muck below. So, there are many reasons for the head bobbing. It is the context of when it is occurring that helps to explain its meaning. We hope this information is of benefit. The Regal Swan