A friend here in the country rescued an injured crow from the property. The birds are very smart. Crow is healthy now and hangs out there, coming to visit/eat several times a day. He comes and lands right beside him when outside doing chores and he can pick him up/get him to sit on his forearm. He has experimented with attaching a small cam to his leg for OPSEC. Still refining it. Agree a balloon would probably be far too noticeable no matter altitude.