Have you seen any scarecrows (稻草人)? In the countryside of our country, some villagers like to set up some scarecrows in the fields in order to prevent birds from harming their crops. They think that this can play a role in driving away birds. In fact, not only farmers love to use scarecrows, but also some airports have installed scarecrows in such a developed technology today, which plays a very good role in driving away birds. Some people will say that birds are not fools, and they will come back to eat after a long time. So do the birds really feel scared? Can scarecrows really play a role in driving away birds? Not very — unless you're willing to put some extra(额外)effort into them.
While traditional scarecrows who couldn't move do work against "pest birds" (eg. crows and blackbirds), the effect is almost always temporary (暂时的). Over time, the birds get used to scarecrows who couldn't move and reuse their destructive (破坏性的)habits.
However, a few tricks can up your scarecrow's game. Researchers have learned that those with realistic facial features(特征)and brightly colored clothes are better at driving away birds. Also, moving a scarecrow around every few days often helps. According to several studies, flailing(大幅波动) scarecrows get the very best results.