I've noticed many of the does are still carrying fawns at my property also. Makes me wonder if the rut was later than normal last fall.

Most birds hatch earlier than mammals are born. This is because most birds have to be adults by the time to migrate in the fall. Normally the larger the bird species the earlier it will hatch. Ground dwelling birds that don't migrate, such as turkey, pheasant etc, are usually hatched later than birds that must migrate.