4 weeks ago we took a 7 year old male Bichon Frise Bertie from an owner whose developing cancer prevented her from caring for him properly.We are retired and my wife wanted a replacement for our sadly missed Cavalier King Charles and in many ways Bertie is ideal - "velcro dog" is a good description. The less ideal habits are that he gets over-excited when I go out (just while opening the door - doesn't attempt to come out with me and soon calms down) and the usual anti postman attitude. We are working on his barking when we both go out. The biggest problem is that when he finds scraps of food when out walking with us he becomes an explosive snarling biting monster if we attempt to take it from him. With his regular meals there is no reaction when we move his dish and he totally ignore us when we are eating. The last straw came this morning when my wife dropped a box that contained a selection of cheeses. As I bent down to pick them up he went for me in a big way and I have several bite marks. If we had got him from a rescue centre he could well be on his way back there but bearing in mind the health of his last owner this is not an option. Is there a way to change this behaviour?