Why guano was imported

 Yes, Europeans imported guano in the 19th century, primarily from Peru and Chile,to use as a natural fertilizer for their agricultural lands.This practice was spurred by the demand for food due to population growth and the Industrial Revolution.Guano,the accumulated droppings of seabirds,was highly valued for its rich nitrogen content,which helped to enrich the soil.

              It sounds like a gross idea but it kind of makes sense.