What bird product was an important fertilizer in the 19th century?
Bat poo Seal shit Bat droppings Birdshit Bat guano Seabird shit Bat shit Bat Shit Batshit Bat poop Guano Phosphate rock island Bird shit Bat paste
seabird shit bat poo bat droppings guano phosphate rock island batshit bird shit bat paste bat guano bat shit bat poop seal shit birdshit
guano
WikipediaEntity
Guano