I wanted to give this one as example:
I had seen one bird of prey in the trees in a field at the other side of a big shopping mall. One time I went out for pictures I went to look for it and found 2 birds of prey sitting in the field next to a busy round-about. I parked my car, set up my 500mm and went on foot to the place where I saw the birds, not to find anything anymore. The next day I set up my 70-200 next to me in the car, when I saw one of the birds again I went to turn, waited for a free road and stopped the car on the road (blocking traffic, so had little time). Drive by shooting gave the best result, I still tried to follow the bird on a parking, in the fields, etc.. never got this quality of result.