It almost seems as if you only had the choice between bird droppings everywhere or a nearly uninhabitable balcony with nets or spikes.
If the pigeons first settle, they can hardly be expelled.
BirdBoggle operates quitly and does not require any external power supply. With a tripod, BirdBoggle is set up quickly and keeps birds away from the environment. Alternatively, a clamp is available with which BirdBoggle can be attached to a table top or to a railing.