Ever since we moved out here, I've been finding little mustard yellow and brown colored spots on the cars. Figuring it was just some sort of palm sap, I really thought nothing of it.
Turns out, it's bee poop. Really. We must have a lot of bees around here, as the spots are everywhere outside.
On the car
On the bathroom skylight
On the grill
Thankfully they wash off rather easily and don't eat into the paint like bird shit can.