I was sitting in a ground blind this past weekend with deer around me(6 feet to 25 yards) and I was having a smoke just enjoying the sites and sounds of a spring fed creek...deer were nervous but coulda been the smell of blood from the buck we arrowed a few hours ealier in the same spot.The sound of me squeezing a water bottle bothered them more.I think it depends on where and the pressure deer have been under.