Guano consists of nitrates, ammonia, along with uric, phosphoric, oxalic, and carbonic acids, and some salts and impurities. This makes it a very effective and sought-after organic fertilizer that increases crop production and improves the quality of food and fodder – it was (and is) so valuable that it has been dubbed “white gold”.
There’s an island (Ichaboe) that lies on
Where penguins have lived since the flood or before,
And raised up a hill there, a mile high or more.
This hill is all guano, and lately ’tis shown,
That finer potatoes and turnips are grown
By means of this compost, than ever were known;
And the peach and the nectarine, the apple, the pear,
Attain such a size, that the gardeners stare,
And cry, “Well, I never saw fruit like that ’ere!”
One cabbage thus reared, as a paper maintains,
Weighed twenty-one stone, thirteen pounds and six grains,
So no wonder Guano celebrity gains.
Ex-member of the Committee (1845)
In his memoirs published in 1832, an American sealing captain,
Injudicious harvesting of guano resulted in severe habitat degradation and disturbance to breeding seabirds; this exacerbates the decline in their populations. African penguins historically nested in burrows excavated from accumulated guano deposits; after the removal of the guano, the birds have been forced to nest on the surface, where they are susceptible to overheating, flooding of nests, disturbance and predation by marauding kelp gulls.Back to top