Birds of prey do not really have the capacity to enjoy flying (although some seem to do more than is necessary), and are designed to sit around conserving energy most of the time. In the northern hemisphere we generally only fly between about August/September around to about March, and in the late spring and summer the hawks are moulting so can’t be flown. During the flying period some species can be flown successfully just at weekends, while some will need to be flown more often to keep them fit. This will be particularly falcons. Whatever you have, remember you have them to fly, not as a garden ornament.