Overall dynamic body acceleration as an indicator of dominance in homing pigeons

The benefits of dominance are well known and numerous, including first access to resources such as food, mates and nesting sites. Less well studied are the potential costs associated with being dominant. Here, the movement of two flocks of domestic homing pigeons (Columba livia), measured via accelerometry loggers, was recorded over a period of two weeks. Movement was then used to calculate each individuals daily overall dynamic body acceleration (ODBA, G), which can be used as a proxy for energy expenditure. The dominance hierarchy of the two flocks was determined via group-level antagonistic interactions, and demonstrated a significantly linear structure. The most dominant bird within each flock was found to move significantly more than conspecifics , on average, c.39% greater than the individual with the next highest degree of movement, indicating a possible cost to possessing the top rank within a hierarchy. Despite the dominance hierarchy being linear, mean daily total ODBA did not reflect a linear nature, with no pattern observed between rank and ODBA, once the top ranked individuals had been accounted for. This suggest that energy expenditure may be more reflective of a despotic hierarchy. These results show the potential for the future use of accelerometery as a tool to study the fusion of energetics and behaviour.