Best Answer - Chosen by Voters
First of all, bird poo is seriously known for carrying diseases, so be careful not to touch it barehanded. Try to lay some bleach down for a little while before you go about this, to kill the diseases.
Believe it or not, Coca Cola is the best known product for removing bird droppings. I don't know what to say about it. Just pour it on, and leave it for about 2 hours, then pressure wash. I'm not kidding in the least. When I was in the NAVY, we had all kinds of cleaning products, but coca cola was what we used for this very purpose. State Troopers in some areas actually keep 2 gallons of CocaCola in the trunk for the specific purpose of cleaning blood off the highway after a wreck. Makes you not want to drink it, huh?