1) Afraid 2) Scared 1) Frightened 2) Given a scare 3) Halloween television episode 4) Scared a bit 5) Scared off 6) Slang for frightened, nervy 
Spooked is slang for frightened, nervy.
One explanation for the sudden departure of a putative lifer, just as you arrive to see it. Often due to nearby raptors but more commonly novice birders twittering loudly near a hide or pointing and waving their excited little arms out through the hide’s viewing flaps.