Guano

Description

The excrement from fish-eating birds and bats that typically accumulates along coastal rocks and in caves. Guano is high in nitrogen and phosphorus and was enthusiastically collected as a fertilizer in the early 19th century. This extensive mining and trade caused the loss of habitat for millions of seabirds as well as the extinction of many species of bats. By the early 20th century, the demand for guano dissipated with the synthetic production of nitrogen containing fertilizers. More recently, guano is being considered a significant problem in public locations and historic sites, due to the extensive damage and staining to stone, metal, and wood. Small amounts of Guanine, a nucleic acid, are extracted from guano and used as a Nacreous pigment called pearl essence.

Synonyms and Related Terms

bird droppings; bat droppings

Physical and Chemical Properties

Guano contains urea and is alkaline.

Resources and Citations

• G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p.323
• Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
• The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 4594
• Wikipedia: Guano Accessed March 2025
• Bill Bryson, ‘At Home: A Short History of Private Life’ Doubleday Publishers, London 2010.