Marine Wildlife Encyclopedia
Guanay Cormorant Phalacrocorax bougainvillii
Boldly marked in black and white, with a conspicuous red patch around each eye, the Guanay cormorant nests in huge colonies along the coast of the Atacama Desert, the most arid region on Earth. It feeds on anchovetas—small fish that abound in the cold waters of the Humboldt Current. Like other cormorants, the Guanay cormorant pursues fish underwater, holding its wings against its body and propelling itself with its legs. It floats low down in the water, periodically dipping its head beneath the surface to check for food. Guanay cormorants have nested on the same offshore islands for millennia, depositing deep layers of desiccated droppings known as guano. During El NiÃ±o years, when the ocean temperature rises, shortage of food forces Guanay cormorants to forage far afield, often as far north as Panama.
Guanay Cormorants and the Guano Trade
Before the invention of synthetic fertilizers, nitrogen-rich guano was an extremely valuable commodity. Thousands of tons were exported from the South American coast to the Northern Hemisphere. Guano was also used in the manufacture of explosives.