Guañape Islands

The Guañape Islands are a small group of islands off the coast of Peru, in the La Libertad Region, made up of Isla Guañape Norte, Isla Guañape Sur, and the smaller Islotes Cantores and Islotes Los Leones, together covering about 0.63 square kilometers with a maximum elevation of 143 meters. Lying in the cold Humboldt Current, the islands are a major seabird breeding ground, home at times to an estimated million birds including white-breasted cormorants, grey pelicans, and white-headed gannets, whose droppings have built up guano deposits 100 to 150 feet thick over the centuries. The birds add an estimated 1,000 tonnes of guano to the islands every year, making the islands' surface layers largely a biological sedimentary accumulation rather than exposed rock.