- Predators: Blue jays are preyed upon by a variety of animals, including hawks, owls, and snakes. They are particularly wary of these predators when they are nesting and raising young.
- Humans: Blue jays can be quite wary of humans, especially if they have had negative experiences with them in the past. For example, if a human has ever tried to catch or harm a blue jay, the bird may become afraid of all humans.
- Loud noises: Blue jays are sensitive to loud noises, and may be startled or frightened by them. This can include noises such as gunshots, fireworks, or even loud music.
- Sudden movements: Blue jays can also be afraid of sudden movements. For example, if they see a person or animal moving quickly, they may be startled or frightened and fly away.