Ever see one that had gotten his eye poked out by a branch from stumbling around in the dark?

Me neither.
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(here's the geeky answer)

They do need some light to be able to see. Their eyes are just much more sensitive than us day-dwellers. They have a membrane in the back of their eye called the tapetum that bounces light back through the retina, giving the tissue a second chance to register the light. That combined with a profuse number of rods that distinguish black and white images give them a very good ability to discern fine contrasts between shades of gray when it is too dark to see colors.