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John, our cities are still full of pigeons. It is not because of lack of sanitary, but because a lot of people, mostly old ones which specially feed them.
As for sparrows you are partly right, P. domesticus became less common in Moscow, it is partly replaced by P. montanus which was uncommon 40 years ago when I was schoolboy. In the northern cities like Murmansk there is only P. domesticus, in small towns around Moscow still more P. domesticus than P. montanus. I suppose that it is a result of heating. If you visit Madagascar or Thailand, you find only P. montanus.