This video from England says about itself:
Lichen loves poop
Ecologist Peter Bremer discovered it by accident: some lichen species like starlings. The droppings of the birds cause some ammonia-loving lichen species to really like roofs used by starlings as a resting place or a singing spot.
Common orange lichen benefits
Especially the common orange lichen (Xanthoria parietina) benefits from the bird droppings. Peter Bremer did his research in a Zwolle neighbourhood, full of houses with concrete tiles. These are ideal for investigation of the relationship between lichens and songbirds. Concrete is a more suitable substrate for lichens than ceramics. Also on the chimneys common orange lichen was found. In the district where Bremer did his research 14 different bird species used the roofs. But starlings were really the most prominent.
- Lichens… So pretty (popperfont.net)
- Rocks, Lichen and Algae (kenneturner.com)
- Richness of Lichen Species, Especially of Threatened Ones, Is Promoted by Management Methods Furthering Stand Continuity (plosone.org)
- A Wet Lichen (therousedbear.wordpress.com)