People who fly their carrier pigeons usually have the bands registered. If you can get the numbers off the band you can find his owners. This happened recently to my Grandfather who lives in south florida, one just landed on his porch he gave it some seed and water, contacted the number on the band (he found a club in the area) and reunited it with the owners. Apparently, not 100%, in order to get them to fly back to where they are supposed to go, they keep the mate (they bond for life) and only release one of the pair that way the carrier bird returns home. Or at least thats what this particular person did that explained it to my G-pa. If you cant get your hands on the bird but have it in a cage then take the cage to a vet and they can towel the bird and get the band. I'm sure the owner would really like to have the bird back.