The importance of guano birds to the Inca Empire and the first conservation measures implemented by humans

Abstract

The Inca Empire was the largest ancient civilization in South America, extending across almost 4000 km of distinct environments from the Pacific coast to the Andes, and throughout most of the arid desert between. The present study highlights the importance of guano birds (Guanay Cormorant Leucocarbo bougainvillii, Peruvian Pelican Pelecanus thagus and Peruvian Booby Sula variegata) for the expansion and prosperity of the Inca Empire. The use of guano as a fertilizer was fundamental to sustain the agricultural development of the empire and, it has been argued, was the basis for its rapid growth. The access to guano on coastal islands and its subsequent transportation to highlands provided food security for a population of more than 8 million. The importance of guano birds to the Inca Empire led to the development of management plans based on a penal code aiming to preserve these species and their natural habitats. These protective actions may represent the first conservation measures ever implemented by humans based on the importance of species protection for human activities and livelihoods.