Red light will not bother them. Like you are thinking, use a small flashlight and get some sort of red lense cover. I have picked up a few over the past couple of years, the head mounted LED combo with 1 red LED, 1 White LED and three bright LED for tracking downed animals. Also have taken a magnum flashlight and use the red lense in it, Kind of heavy but fun for using when I have the kids. I also use a 1Million candle power with red lense to spotlight pigs and look at Deer in my yard at night.

Good luck.