Aie, all this talk about feeding the pidgeons cyanide so they vomit all over the parking lot and die, or feeding them rice so their stomachs rupture. A bit gruesome, if not plain malicious, yes? Certainly not attributes deserving of people like us in this day and age.
Listbard, that's like saying it's not your fault that your kids died when you fed them arsenic-laced Cornflakes; it was their gluttony that was their undoing.

Not an excuse that'll fly (no pun intended, hah).
Bilbous, if you truly want to do the course of action that requires the least amount of effort, why don't you just ask your landlord to install plastic spikes on your railing for you? He does after all, own the railings, does he not? They don't look THAT bad after a while ... although I might just be saying that because I've gotten used to seeing them myself. But hey, no pidgeons on this end!