Pretty much what everyone else is saying.

From everything I have read buck mortality is much higher from nonhunting deaths. They travel much more during the rut, exposing themselves to many more road crossings.( we all know what can happen there) And the wear and tear of the rut takes quite a few more bucks that it does does.(those last 2 words look strange together)Specially in really bad winters. And how many does do you know of that die from fighting or wounds during the rut.

Those things added to the many more bucks harvested during the hunting season, and it doesn't look good for the balanced sex ratio.