We have two Magpies who are gathering twigs to shore up their nest in a tree on the other side of the road. They are in competition with cats, blackbirds, and seagulls.
As regards birds, I visited the church in Foots Cray near Sidcup last summer, and all around me in the trees there were hundreds of screeching Cocateals, definitely parrot-type birds and orangey in colour. I presume they escaped from somewhere and have just multiplied in numbers. Are they in other parts of London and in other parts of the country as well??