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The guano trade began on three tiny Peruvian islands in the Pacific, and their product reached farmers’ fields around the world.
The three tiny Chincha Islands lie off the southern coast of Peru. For millennia, they served as home for seabirds. The birds fed and bred in the rich waters packed with fish and absent of predators, allowing their droppings to accumulate to a depth of up to 200 feet. The dry weather and cool ocean currents there maintained the guano’s nitrate-rich quality.
In the early 19th century, farmers and chemists worldwide claimed that Chincha Islands guano was the world’s finest fertilizer. Hundreds of British, German, and American ships purchased it from the Peruvian government for their own agriculture, waiting offshore up to eight months to load the precious cargo. These nations’ ships also sought, claimed, and mined other guano islands in the Pacific and Caribbean.
Although they recognized the practices weren’t sustainable, they continued to harvest the guano. By the late 1870s, nearly all of the Chincha Islands guano was gone, and the seabird habitat was ruined by the mining operations.