no, the BJs never fly over their fencing (mine anyway--someone else's BJs might!) maybe they would if it was shorter. i have never had a bird fly over the six ft, but my olive egger pullets fly out of their 4 ft all the time (and sometimes into the six feet pen--but none of the roos seem to fly over anything, whether BJ, EE, FCBM, or AA). the fence was not closed back properly, so i am pretty sure it was a tourist.