I will agree with Halfbaked to a point.

The does determines which deer stays and which deer leaves.

Last years button bucks and spikes are chased away due to the fact that they realize that they don't want to be inbred by one of their own offspring. So once the doe determines that this little buck does not belong here anymore, she gets down right mean and ornery with him until he leaves.

The other thing is - if big daddy is around, he doesn't want this little buck competing with him for breeding rights with his does - so he will chase the little buck away also.

My guess is that the little buck will travel 3 to 10 miles away until it can find a place where it is accepted. As the larger bucks are shot off the smaller bucks takes over the breeding chores. Each doe will come in heat once a month until a buck gets her pregnant.
Some does don't get pregnant until spring. I have seen fawns in December before - but I don't know what the mortality rate is for fawns born late - but I would guess that it is as bad as or worse then ones that were born in the spring and had all summer to grow and all fall to fatten up.

Last winter, with its deep snows and cold weather for months on end had to have a large impact on the deer herd. Many of the turkeys did not make it through the winter season either.