guano n : the excrement of sea birds; used as fertilizer

English

Etymology

From guano, from huanu.

Pronunciation

• Rhymes: -ɑːnəʊ

Noun

1. Dung from a sea bird or from a bat.

Translations

Quotations

• 1982: "grazes on bat excrement, delicately referred to as ‘bat guano’ in this week's Nature." —physics!tpkq, net.games.rogue
• 1995: "The great white bat has great white guano!" —Jim Carrey, Ace Ventura: When Nature Calls

For other uses, see Guano (disambiguation).

Guano (from the Quechua 'wanu', via Spanish) is the feces of seabirds, bats, and seals .

It is an effective fertilizer and gunpowder ingredient due to its high levels of phosphorus and nitrogen and also its lack of odor. Superphosphate made from guano is used for aerial topdressing. Soil that is deficient in organic matter can be made much more productive by addition of this manure.

Usage

Guano consists of ammonia, along with uric, phosphoric, oxalic, and carbonic acids, as well as some earth salts and impurities. Guano also has a high concentration of nitrates.

It is estimated that there is only enough phosphorus from current resources to last about 30 years. This is a problem as vast volumes of phosphorus are needed to produce fertilizer, as it is an essential plant macronutrient. Guano is rich in phosphorus and is an effective phosphorus fertilizer.

Sourcing

The ideal type of guano is found in exceptionally dry climates, as rainwater drains the guano of nitrates. Guano is harvested on various islands in the Pacific Ocean (for example the Chincha Islands and Nauru) and in other oceans (for example Juan de Nova Island). These islands have been home to mass seabird colonies for many centuries, and the guano has collected to a depth of many metres. In the 19th century, Peru was famous for its supply of guano.

Bat guano is usually mined in caves and is associated with a corresponding loss of troglobytic biota and diminishing of biodiversity. Guano deposits support a great variety of cave-adapted invertebrate species, which rely on bat feces as their sole nutrient input. In addition to the biological component, deep guano deposits contain local paleoclimatic records in strata that have built up over thousand of years, which are unrecoverable once disturbed.

The greatest damage caused by mining to caves with extant guano deposits is to the bat colonies themselves. Bats are highly vulnerable to regular disturbance to their roosts. Some species, such as P. aphylla, have low fat reserves, and will starve to death when regularly disturbed and put into a panic state during their resting period. Many species will drop pups when in panic, with subsequent death, leading to a steady reduction in population. Research in Jamaica has shown that mining for bat guano is directly related to the loss of bat species, associated invertebrates and fungi, and is the greatest threat to bat caves on the island.

One of the major innovators in guano harvesting was Benjamin Drake Van Wissen.

Guano has been harvested over several centuries along the coast of Peru, where islands and rocky shores have been sheltered from humans and predators. The Guanay Cormorant has historically been the most important producer of guano; its guano is richer in nitrogen than guano from other seabirds. Other important guano producing species off the coast of Peru are the Peruvian Pelican and the Peruvian Booby.

The high concentration of nitrates also made guano an important strategic commodity, with the War of the Pacific between the Peru-Bolivia alliance and Chile was primarily based upon Bolivia's attempt to tax Chilean guano harvesters.

References

See also

• Guano Islands Act
• Feces
• Economy of Nauru
• Phosphate rock

External links

• ProAbonos
• Jamaican Bat Guano and Cave Preservation
• Is there Guano in Mascara? - Good Organic Gardening Reference