PM sent - I may be able to help you out with all your troubles!!!
In Scotland there is a requirement be registered with your local wildlife officer and a tag on the trap with his contact details and your trap number on it. Check out the Scottish Office site
http://www.scotland.gov.uk/Publications/2007/01/04143731/6 for full details.
I fell foul of this two years ago when the law was changed and the tag thing was introduced. A 'kind' member of the public reported the bird was in a cage on my ground and I came home to find two SSPCA guys removing the bird for a
VET TO EXAMINE to ensure I hadnt been cruel and unkind to it. They had called the Police to enter my property under escort to examine the bird. It was quite evident there was food and water for it along with a shelter area and three different types of perch. The trap was not in operation at the time but the officer was quite firm in his assurance that there would be further action should they prove negligence on my part. Once the vet report came back that the bird was plump and healthy but had a bashed tail feather they passed the details onto the local Procurator Fiscal to deal with it. Allegedly it was held in an aviary until the courts decided what to do. I never heard a thing about it again admittedly but i was a bit upset and angry about it as they had
confiscated the bird and made me feel like some master criminal with the comments about vet checks and prosecution. All I had done wrong was not have the tag on the cage!!! My insurance company provided a lawyer to pursue the case and he tore strips off of them for the hassle that the whole thing caused. Suffice to say the one I operate now is tagged and registered but I am carefull about where its located now.