I have witnessed on several occasions deer moving in the rain, with their heads down close to the ground. Doesn't sound like a big thing until you know they were crossing open fields with grass that covered their heads.....................until you let out a whistle & they would stop & raise their heads(shoot)! Works good on whitetails in the south..............................doesn't work worth a crap on Elk, they RUUUNNNNNNNNNnnnnnnn! My 2 cents