PREFACE 



To meet a long-existing demand for a guide that in concise and 

 convenient form will enable students to identify in the field birds 

 of southern California and Arizona, the " Birds of the Southwest- 

 ern United States" is herewith presented. 



The territorj'- considered includes all of Arizona, and that part 

 of Nevada and California lying south of a line drawn from extreme 

 northwestern Arizona, west and south through the mountain bar- 

 rier fringing the southern end of the great central valley of 

 California, to the ocean. 



This area possesses the most varied and interesting avifauna of 

 any part of North America. Of the four North American Swifts, 

 the three exclusively western forms occur within our limits. 

 Ranging from lowest deserts to highest mountains are found 

 eleven species of Hummingbirds, as compared with only one east 

 of the Mississippi ; while five species of Quail contrast with the one 

 of the eastern United States. In southern California is Mount San 

 Jacinto, noted in biological reports, where proximity of high 

 mountain and below-sea-level desert has produced a remarkable 

 concentration of Life Zones, each with its characteristic species. 

 Arizona attracts world-wide travel with its Grand Canyon drop- 

 ping from a plateau of 6000 feet elevation to the narrow river 

 gorge a mile below. Here in a day's trip we find birds and plants 

 of three Life Zones corresponding to the 1000 miles of latitude 

 between Mexico and Canada; while near by are the San Francisco 

 Peaks, rising to nearly 13,000 feet, and carrying the Life Zones 

 up through the Boreal, the whole equivalent to a northward 

 advance to Arctic shores. 



This bird-guide will be welcomed by those who feel the peren- 

 nial charm of the desert. Only a few times in a century do the 

 meager rains come so well timed as to produce the galaxy of color 

 which is the miracle of desert springtime and which passes like a 

 dream. But during all the year the bird residents give life and 

 charm even to gray, leafless shrubs and sun-scorched landscapes. 



