Norwich is one of my favourite cities,
I was in holiday a few years back in Callender, went for a walk in the local park and was thrilled to find red breasted mergansers coming for food with the rest of the ducks. Just goes to show how one areas rarity is another areas common bird.
Similar thing happened in the London wetland centre, I went to the shop on the way out and checked the latest sightings, realised I had a few that were not on their list asked if they weren't on there because they were so common... Only to find out they were locally scarce. Can't even remember what it was, but something I am used to like siskin or something like that.