Hunting is an activity that comes with a certain amount of risk, and hunters know that. Just hiking in the woods can be risky, even if you do everything right.
When something out of the ordinary happens while you're out in the woods, it can be enough to scare the pants off even the most seasoned of hunters.
Speaking from personal experience, there are fewer things as freaky as the scream of a cougar in the middle of the night when you're sound asleep.