noun
scarecrow; bird rattle; clapper
A device placed in fields to scare away birds, ranging from a traditional scarecrow to a noise-making clapper or rattle.
田んぼに鳥おどしを立てた。
We set up a scarecrow in the rice field.
風で鳥おどしがカタカタと鳴った。
The bird rattle clattered in the wind.
かかし is the common word for a human-shaped scarecrow, while 鳥おどし includes various bird-scaring devices, not necessarily human-shaped.
Compound of 鳥 (bird) and おどし (scaring), the nominalized form of おどす (to scare).