PERU'S WEALTH-PRODUCING BIRDS 



Vast Riches in the Guano Deposits of Cormorants, 



Pelicans, and Petrels which Nest on Her 



Barren, Rainless Coast 



By R. E. Coker 



With Illustrations from Photographs by the Author 



PERU is preeminently a land of con- 

 trasts. A visitor standing upon 

 some moderate eminence by the sea 

 may gaze alternately upon the broadest 

 extension of ocean's smooth surface and 

 the highest and most battlemented moun- 

 tains of the continent. 



If his vision weary of the barren desert 

 stretching between sea and snow-clad 

 peaks, he has but to turn in his tracks to 

 refresh his eyes with the beauty of a ver- 

 dant tropical valley, where brightly col- 

 ored birds flit among trees and shrubbery 

 and tropical fruits are watered by melted 

 snows. 



The daylight about him is perhaps as 

 brilliant, as dazzling, as sunlight may be 

 upon earth, while he breathes deeply the 

 moderately cool sea breeze blowing fresh 

 from the mighty Humboldt Stream. 



He will become enervated by the rays 

 of the tropical sun pouring direct from 

 the zenith, but he may stroll down to the 

 beach and plunge into a surf as cool and 

 invigorating as that of Martha's Vine- 

 yard or Monterey. 



The paradoxes of Peru might be multi- 

 plied, but our interest lies not immedi- 

 ately in these. Rather we are concerned 

 with other links in the chain of circum- 

 stances arising from the same funda- 

 mental geographical causes. 



why peru's coast is rainless 



The Humboldt, or Peruvian, Current, 

 supplemented no doubt by the upturning 

 of cold bottom waters, maintains its 

 steady course for thousands of miles, 

 from icy Antarctic latitudes to the Equa- 

 tor. Thus it is that tropical shores are 

 bathed by cold ocean waters, and, with 

 this fundamental contrast, the stage is set 

 for an array of phenomena not fully 

 paralleled in any other part of the world. 



Only two events in that interesting 

 series command our present attention. 

 These are the absence of rainfall and the 

 consequent accumulation, through centu- 

 ries untold, of a mine of wealth which 

 might have been dissipated by a few sea- 

 sons of rain. 



The cause of rain, of course, is the 

 cooling and contraction of a moisture- 

 laden atmosphere. We may think of a 

 wet sponge that is squeezed and forced 

 to give up its water ; but when a moist, 

 cool breeze is warmed over sunny lands, 

 it is as if a compressed damp sponge 

 were allowed to expand ; instead of giv- 

 ing up water, the sponge is drier than 

 before. 



So, when the winds blowing cool from 

 the surface of the Peruvian Current 

 touch the lands that are warmed beneath 

 a tropical sun, expansion or rarefaction 

 occurs, rainfall is prevented, and the at- 

 mosphere is dry. 



peru's dry atmosphere preserves its 

 guano wealth 



The significance of this, with respect 

 to the famed guano deposits of Peru, 

 easily becomes apparent. In climates of 

 common atmospheric humidity, however 

 numerous the sea-fowl that nest or rest 

 upon islands or mainland, the nitrates of 

 the guano give rise to ammonia and are 

 wasted by evaporation or seepage ; but 

 when, as in Peru, year after year guano 

 is laid down beneath a clear, dry atmos- 

 phere, the deposit bakes in the sun and 

 its most valuable components are im- 

 prisoned for an indefinite period. 



Guano, it will be understood, is pri- 

 marily the deposit of fish-eating birds, 

 into which may be mixed and incorpo- 

 rated — in greater or less proportion — a 

 variety of other substances, such as the 



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