Dispersal of close relatives within a breeding colony of European bee-eaters, Merops aptaster, was investigated by comparing the spatial separation of breeding relatives with that between the same individual and a control individual hatched nearby in the same year. One-year-old males breed closer to their brothers, but not to their parents, than do controls. The main benefit of breeding in proximity to relatives appears to be enhanced helping behavior: potential helpers are more likely to help and to help more quickly after nest failure when their own nest is close to that of the potential recipient of help. Breeding in proximity to relatives also appears to carry a cost because nest failure is spatially aggregated: this implies that individuals breeding close to relatives are less likely to have a relative available to help should their own breeding attempt fail. There was no evidence that the proximity of relatives enhanced nest establishment, defense against predators, or information transfer. © 1994 International Society for Behavioral Ecology.
