Thanks all for comments. I've got a scanner and don't think he's chipped. The plan is to befriend him further, and put a paper collar on with my contact details to make absolutely sure he's not owned. Meantime I wish people would neuter!
We have bees nesting in our chimney, which is currently being repaired by builders who aren't bee enthusiasts... any beekeepers out there with any suggestions re what to do? Can they be moved?