Have you ever been pooped on by a bird? My son insists that's "pee' - not "poop" - (something he learned in school) - but anyway, of course you've been in the "poop cross hairs."
Anywhere birds of any kind congregate, there's poop. If this is an area frequented by humankind, it's messy & unhealthy. For years, city leaders have tried to find a way to repel birds. No birds - No poop. Sounds simple. It isn't.
Here in Springfield we have pigeons that roost on the Capital Building roof. They've "greased the ledges" - sprayed predator pee - and even blasted horns. Nothings really worked. Ask anyone who parks their car at the Capital if the bird deterrents have worked. You'll get a speedy reply. "No!"
Recently a company began selling a "Bird spike strip." Simply place it on any ledge you want to keep birds from landing on. The birds float their butts onto the razor like spikes - and you'd think - fly away. Some do. Many simply impale their bird bodies onto the spikes and fall dead.
Ask the people that park their cars under ledges with "Bird spike strips" - if they work as intended. You'll get a speedy reply as they brush the dead birds from their car, "No!"
The city of Chicago is next with a brilliant plan to get rid of birds. The birds in question here are actually Canadian Geese. They're eating the grass in Grant Park. The Chicago Park District just spread 200 gallons of a "digestive irritant'. The chemical is supposed to give the Geese diarrhea within 20 minutes. The geese are then supposed to "get the idea" and leave. In a couple of weeks, ask Grant Park visitors who've been beneath Canadian Geese with explosive diarrhea if this was a good idea. I can tell you the answer now. "No!"