I would think that if you ride the area you hunt often on an ATV that the deer would ignore it but also think deer say here they come, hide.
I hunt 1200 private acres in NE PA. There are 3 or 4 trails through the area. I ride it often in an ATV or a UTV. I ride up next to deer and bear often, sometimes less than 10 or 12 feet. Some animals do spook but they are a low percentage.
I think they believe it is just another vehicle and most exhibit little if any fear.
If I walk that same area I am not going to get close to any animal. They will be gone as soon as they detect me.
I should note that we have never hunted any animal from an ATV and never gave them a reason to fear an ATV.
