This particular bird is quite aggressive, although it has never made contact with my head, (unlike the one in the photo) it swoops me for at least 500 metres. At least the cars wizzing past have some entertainment at my expense.
Talking to other riders we all have our training loops and know where these kamikaze birds are located. They can give you a fair whack on the helmet sometimes and I remember one near the golf course just out of Wangaratta, heading towards Yarrawonga, that is a real nasty bugger (it is the bird in the photograph). I'm sure there are plenty of experiences like this and it's not isolated to cyclists.