The word “guano” originates from the South American Andes, and means “the droppings of sea birds”
Seabird guano is a prized fertilizer due to its high phosphorus and nitrogen content. You can buy it at most garden stores, and I’ve even used it on tomatoes here in Alaska!
Waters off the coast of Peru are highly productive and support millions of seabirds. The combination of many seabirds and lack of rain means that seabird guano quickly builds up at the breeding colonies.
Seabird guano has been harvested commercially for over 150 years, and was even used by pre-Colombian Native Americans for agriculture. The three main guano species are the Peruvian Booby, the Peruvian Pelican, and the Guanay Cormorant.
The Peruvian islands are currently harvested every 7-10 years by up to several hundred laborers who visit the islands between the guano birds’ breeding seasons.
Landing Stage dock for guano ships in Peru.
Copyright Mikey Stephens via Creative Commons.