Photo: Alejandro Balaguer

Photo: Alejandro Balaguer

From our bird's eye view we would also see, standing off the coast in the cooling stream of the Humboldt Current, over 150 islands of varying sizes scattered at random. 66 of these islands are a brilliant white, looking for all the world like lost snowcaps. These islands are the haunt of the guano birds, whose droppings, with their stench of ammonia, have been used as fertilizer since pre-Inca times.

The Humboldt Current is not the only natural phenomenon responsible for shaping this marine ecosystem. Plankton-rich upwellings of colder water - when the warm Niño Current isn't upsetting the normal order of things - attract a rich supply of fish that have encouraged thousands of marine creatures to make their home on these islands.

At dawn the pelicans shake out their sleep-laden wings, and the boobies swoop overhead, every so often hurtling arrowlike into the sea to catch the pilchard that abound in these waters. Meanwhile, the black cormorants - or guanay to the natives - wait patiently on rocky ledges for the first rays of the sun. As their Peruvian name suggests, these birds, found on all the islands along the Humboldt Current, are the main producers of guano. They share their rocky habitats with sealions, penguins, black skimmers, red-legged cormorants, Incan terns and gulls.

The peculiar climate of the Peruvian coast, featuring light winds, almost zero rainfall - except for the occasional light drizzle, and perpetual sunshine, enabled the guano deposits to build up over immense stretches of time into layers - some as old as the pyramids - as much as 150 meters deep.

In 1802 the German geographer and naturalist, Alexander von Humboldt, took a few samples back to Europe, in order to analyse them. However, it wasn't until 1840 that Baron Liebig demonstrated the virtues of guano as a first-rate fertilizer. It was then that the Peruvians realized that thankfully the Spaniards hadn't completely beggared the country when they made off with its gold and silver. The guano boom came in the nick of time to save Peru from dire economic straits. The country exported almost its entire supply of guano, an estimated 40 million tons in all, mainly to Europe. The proceeds enabled the country to pay off the national debt, with enough left over for major infrastructure projects, including an extensive railway.

The islands off Chincha, which had the biggest deposits, were the first to be harvested. Once exhausted, attention turned to the islands of Lobos, Guañape and Macabí. After digging for a time, workers began turning up hundreds of pre-hispanic artifacts, including solid gold and silver burial ornaments, wooden idols and utensils, fine metal weaving tools and huge shrouds of cotton fabric. Today these items are on view in museums in Hamburg.

However, all that survives of the most significant finds are a handful of chroniclers' accounts: «...in 1867 on the islands of Chincha and Guañape several female corpses were found with their heads missing and their breasts and flanks covered with thin pieces of gold foil.» The pelicans and migrating birds of those times probably had more respect for the Chincha and Chimu civilizations than the guano diggers, who merely pocketed the gold and threw the remains into the sea. These pre-Incan civilizations associated fertility with the land and women. They sacrificed young maidens to the sun and buried them on the guano islands, their sacred burial grounds.

The guano finally ran out in 1870. Since then, the guano birds are only disturbed every seven years, when gangs of men arrive with nets and sacks to pick up the feathers and dead birds and, using picks and shovels, collect the guano until the birds are left with a new island canvas to paint white. When the men leave, the birds return to their tranquil routine of producing the rich fertilizer, a natural alternative, still used today.

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