Guano
Guano is the excrement of bats and birds. This excrement is exceptionally high in nitrogen, phosphate, and potassium, three nutrients which are essential for plant growth. Therefore, it is often used as fertilizer, to make plants grow more quickly.
Guano Media
Man-made Guano Island near Walvis Bay in Namibia
The guanay cormorant has historically been the most important producer of guano.
Insectivorous bats, such as this Mexican free-tailed bat, have historically been the most important producers of bat guano.
Aerial view of Guano Point. Old tramway headhouse is at the end of dirt road (right). Second tramway tower is more clearly visible, on skyline to right. Bat Cave mine is 760 m (2,500 ft) below, across the canyon.