Strolling in the garden with my macaw, he can't fly but he is sure aware when a hawk hangs over our heads, so I know even if it is so high all I see is a speck.
Cool catch- you expect to see him in a tropical setting- but there he is with fir trees and field! That's pretty interesting that he can sense the predator even when you can't really see it. Must help in their natural habitat too.
