Researchers have found that shouting is more effective than speaking when trying to scare off seagulls. The study published Wednesday tested how 61 European herring gulls reacted to different sounds. They included a robin’s song, a man’s voice speaking and a man’s voice shouting. The gulls tended to walk away from the speaking voice but flew away from the shouting. This suggests they can differentiate between the acoustic properties of vocalizations. The experiment showed that you don’t need to lash out at the birds to frighten them. Further studies could explore reactions to female voices.