Scary for birds, scary for humans.
A scarecrow, or hay man, is a mannequin in the shape of a human used to scare crows and sparrows. Scarecrows are usually made of straw and dressed with old clothes. Unfortunately, crows soon become familiar and scarecrows cease to be of any use whatever. While modern times have declined the use of this decoy, it is still seen in some farms serving their original purpose or as fall decorations. The fact that some people find them scary is because the adding of an evil-looking jack-o-lantern placed as a head, the vague Christ-like look or the feeling that they look like corpses propped up, someone imprisoned or hiding, becoming the perfect nightmare fuel during Halloween.
Can be made at home with the right materials.