When they are hot on a doe, it's almost impossible to get them to stop. If you can whistle loudly, that may work, but only do it while they are moving quickly. If he's alone, and just moving on, I don't like to whistle, then I grunt softly, with my voice. I can do it with some good volume too, but there have been times that even a lone buck on the move in november won't even stop for that.

Another thing I've done, is do something to stop the doe. If she's in eye sight of you, and moving fast, and he's close behind, I'll just flat out move so she catches my eye. A lot of times she will stop to see what the hel you are, and they buck will about run her over. Sometimes I'll grunt at her before she even gets within bow range if I can see her coming and I know she's gonna come right by me. It'll get her attention, sometimes slow her down, and if you can pass her visual test, she may just stroll by and bring the buck past in a much more controlled fashion. If he's walking, following her, he may stop at your grunt.

No 2 situations are alike, so gotta play it by the seat of your pants. They are already running, the worst that can happen is they run faster!