Based on the responses so far, I was starting to think along the same lines myself. It seems very unlikely to me that lightning would hit the camera directly, most probably it would hit the tree first and then arc over to it. So if I enclose the camera and cable in plastic and then run an earth cable up the opposite side of the tree as atropine is considering, it should direct the lightning safely to ground while keeping it far from the camera, right? In case it helps I'm planning on placing the camera about 15 feet up, and the tree is much taller than that. It's a wireless cam with built-in antenna, so no data cables to worry about.
VTS_Man and Rooney care to weigh in on this idea?
Thanks to each of you for your thoughts so far, I'm learning a lot already.