There is a interesting topic on HuntingPa.com about peeing in a bottle while hunting, and whether or not human urine spooks deer. The common denominator by the majority of responses says "NO it doesnt spook deer and quite the contrary" What about spooking predators?
Last weekend when I showed up to hunt at a spot, I realized I had to take a severe dump. I ended up driving a mile up the road to dump in the woods.