PERU'S WEALTH-PRODUCING BTRDS 



547 



IMMATURE PIOUEROS IN A ROOKERY ON ONE OF THE EOBOS DE AFUERA ISLANDS 



There is scarcely an island or a high point of shore along the Peruvian seacoast whose 

 steeper walls are not dotted with the nests of piqneros, also known as Peruvian gannets and 

 camanays. 



dreds of intent green eyes may well hold 

 the attention. 



The confused sound of countless croak- 

 ing voices that rise or fall with the state 

 of alarm in the multitude makes an effect 

 comparable to the sullen mutterings of a 

 disgruntled mob of human beings. 



While some cormorants, when not 

 nesting, seem to know the land only as a 

 place from which to dive, guanays in 

 multitudes will rest for hours upon the 

 level ground. They generally walk more 

 than their near relatives, and as an in- 

 dividual bird strolls about in its small 

 circle, the erect, waddling gait inevitably 

 suggests the penguin. At a casual glance 

 the birds shown in one of the illustra- 

 tions (page 542) might well be mistaken 

 for penguins. In flight they form long, 

 black clouds miles in length, streaming 

 low over the water until they settle down 

 to form a large, black blotch on the sur- 

 face of the sea. 



The guanay well deserves its common 

 name. Its gregarious habit, its choice of 

 the level places or more gentle slopes for 

 nesting grounds, and its custom of re- 



maining on the islands a great part of 

 the time, all combine to cause the forma- 

 tion of enormous deposits of guano, from 

 which there is little natural waste. The 

 guano is also of exceedingly high value 

 in nitrogen compounds. 



In the region where this bird was most 

 abundant, about the Chinchas and Bal- 

 lestas Islands, the climatic conditions 

 were most favorable to the preservation 

 of the nitrates. It is doubtful if the 

 guano of the Chincha and Ballestas 

 Islands is ever wet from atmospheric 

 moisture. 



Even though these islands were visited 

 by the writer during the winter months, 

 when the garua, or Peruvian fog, pre- 

 vailed 'upon the coast, the atmosphere 

 was invariably dry and clear. Conse- 

 quently the nitrates are effectively pre- 

 served, and 14 to 16 per cent and more 

 of nitrogen may be found regularly in 

 the comparatively new guanos, while 

 even the ancient deposits showed nitro- 

 gen in proportion of 12 and 14 per cent. 



When the islands were closed by the 

 government, in 1906, from the period of 



