John--I'm the same way, but my brother loves the hiking side of things and covers an amazing amount of ground (and takes lots of fine photos). He is useful in that he always checks out small tributary streams for trout and duly reports to yours truly.
Snakes have been mentioned several times in this thread, and I would simply point out that on a personal basis, at least, I'm more likely to encounter a poisonous one in my yard than in the Park. This morning, while getting up some trash under a Stayman apple on the lower part of the property (three acres with some woods, a big garden, and lots of grape and scuppernong vines, fruit trees, blueberry bushes, raspberry and thornless blackberry vines, etc.) I noticed movement. Sure enough, it was a cooperhead of 26-28 inches. It' either the fifth or sixth one I've killed on the place, with one of them being scary (pulling weeds by hand and saw movement right at my hand).
As I've said, they don't overly concern me, and this particular one won't concern anyone, except possibly the buzzrds, henceforth.