I have owned several birds including my African grey, Walter. I also worked at a pet store for a time cleaning all of the bird cages daily. I have to say as a group, the lovebirds tended to be the messiest. My Grey, Walter is not exactly neat and takes great joy in flinging out bird food to the dog who comes to eat it. (I don't understand it either but they have this relationship). Another interesting thing Walter does is to sort out his pellets. Some days he would eat the purple and fling the orange, other days he would collect the red and dump the purple. I guess it is just a game for him but it drives me nuts. Now he has gone through a phase where he refuses to eat the pellets at all.