RE: Using a light
Interesting non-reaction to flashlight ...
In the early morning, I keep the light on my path, take a few steps, turn the light off, stop and listen. A couple of weeks ago, I heard a deer close by and turned the light back on. She was about 5 yards away walking broadside and browsing. The light was on her body (not in her eyes) and she didn't react at all. I turned the light off and started to squat down. As I started to move, she bolted away.
I didn't make any sound (that my human ears could here anyway). My reasoning about the reaction is that deer see as well at night as during the day. They are nocturnal animals after all. Because there is no glare, it is possible that their vision is better at night than during the day. The light itself may not contrast the dark in the deer's view. Deer will respond to any movement whether it was made in the dark or in broad daylight. I feel strongly that if you walk with a flashlight it will be your "walking" that spooks the deer ... not the light itself.