Outdoor catio sounds like the ideal thing for you. In pigeon terms , It is referred to as an Aviary. You can install a trap on one of the walls. Easy to build yourself, and all you need to get are the bobs. Can make your own,,, but they are reasonably priced.
Here is an example of...
First,,, WELCOME to BYC and this pigeon forum.
Thank you for rescuing those 2 pigeons. :hugs ,, Now some questions to clarify. Just what do you mean by free ranging??? I kind of understand that you let your pigeons free fly. Am I correct?? In pigeon keepers terms.. that is called...