The Ballestas Island in Peru, like the other 21 islands along the Peruvian coast, is home to nearly 4 million migratory birds such as guanays, boobies and pelicans.

These birds' nest on the island, located south of Lima, and their excreta make up for the world's finest natural fertilizer.

The bird dung, also known as guano, reached its greatest economic importance in the 19th century as a coveted resource being exported to the United States, England and France, reports Reuters.

According to the Rural Agrarian Productive Development Program (Agrorural) reports, the current guano production in Peruvian island is about 20 thousand tons per year.

Peru hopes to benefit mostly small farmers by boosting organic agriculture through these natural fertilizers.

Check out some of the pictures of collection and processing of guano at Ballestas Island.