"I haven't seen winged cats in particular. I have seen a winged rabbit - with added antlers for some reason - which glided fairly competently if it started from a height, and could get rather more airtime when it leapt than an unimproved rabbit, and a winged shrew, which could in fact fly properly. Any of these creatures would probably be engineered to sufficiently picky eating that it wouldn't attack wild fauna, anyway. There was a tremendous fad for making winged things about a decade before I was born and some of them are still around. At one time it was suggested that haut could be made to have wings, and fly with them too, but this, along with revising our eye designs to avoid the blind spot and other dramatic anatomical changes, was ruled out on the grounds that we weren't at the point where we wanted to sacrifice the theoretical ability to reproduce without design intervention with - there's really no polite word for humans without engineering done, is there."