Stinkbirds, otherwise known as hoatzins, have spread out across South America in part because they have something in common with humans and other mammals. The clue is in the name “stinkbird.”
On the other hand, Hoatzins don’t produce great mounds of birdshit. The reason that urban Canada geese are such profuse shitters is that they are grazers, but lack the Hoatzin’s gut adaptations for getting the most out of a diet consisting mainly of leaves. So they have to eat a lot of fodder in order to get anything out of it with their inadequate digestive systems, and of course this results in a massive output.
On the plus side, geese can still fly really well.