How do I help a lost pigeon?

Hello - I am afraid I am an imposter here as I know nothing about pigeons. I am an animal lover though, and am very concerned about a pigeon who I think is lost. I hope someone here can help and that you don't mind me asking.

He is a beautiful bird and looks like he's been very well looked after. He has a green tag around one of his feet. He's been hanging around our block of houses for about two weeks now, completely alone - he doesn't seem to be with a flock or anything. He never leaves the block and he sleeps on our roof at night. I feel sorry for him, I think he must have gotten lost. What is he going to do in the winter - does he even know how to build a nest? He will freeze up on our roof, surely!

How can we look after this pigeon? Should we build him some kind of bird box to sleep in? He seems so lonely

Any advice would be much appreciated!

Thanks

hello,if you can catch the bird would be the best thing,,,we could then be able to tell you where it is from and who owns it...someone on here will know of someway how to catch it then we can take it from there

yes as ray said try and catch the bird and write down the ring number and put it on the latest topics and we can tell you the owner