The Shadow falls silent, watching the sky for a time before his eyes close. There is little sign to betray it, but after a short while she just may realize that he has in fact dozed off. He is a very light sleeper, but after nights of waking repeatedly from disturbing dreams, this is some much-needed rest.
The moment she grows restless, that motion wakes him, and he shifts soundlessly from sleep into alertness, then carefully sits up and stretches. A brief nap has left him ready for whatever further hiking she'd like, and the return flight after. He is used to catching his sleep in bits and pieces.