Toss up fire crackers??? I actually condition mine to startle ect when i whistle hard and sharp, as after do when in loft i then chase with broom flag ect not actually hurting but just so then they fly out or up on command, break to roll ect together, or watch for bop. oddly mostly they kit better if seperating too, so maybe they use same as when chickens do similar sound as alarm call when threat seen by one..