| 摘要 |
A bird scaring apparatus 10 comprises a plurality of loudspeakers 17, and a signal controller 22 that is arranged to cause the loudspeakers to generate a bird scaring sound at intervals, and is arranged to vary the sound with time by: (a) varying the loudness of the bird-scaring sound; and also (b) generating the sound with only a selection of the loudspeakers rather than all the loudspeakers and changing the selection of loudspeakers during the generation of the bird-scaring sound. The bird-scaring sound may be a distress call of the bird species that is to be scared. Varying the loudness of the sound ensures that birds at a variety of different distances from the apparatus will hear the bird-scaring sound at an appropriate volume. Changing the selection of loudspeakers gives the birds the impression that a predator is moving around. The combination of these ways to vary sound is therefore beneficial in scaring and dispersing birds in a humane fashion. |
