THE UNCHARTED SKY 143 



Cheeked Thrush from Quebec and the little Black- 

 poll Warbler from far-off Alaska." 



"But if it's food they're lookin' for, why 

 wouldn't a land-bird follow the land an' go down 

 by Mexico?" 



*'Just because there's no food," came the 

 prompt reply. ''A long flight doesn't worry a 

 bird much, as long as he has a good meal before he 

 starts and a good meal when he arrives. Little 

 nibbles along the way don't interest him. On that 

 Mexican route you have suggested, there is hardly 

 anything to eat. Arizona and New Mexico, with 

 arid climates, afford comparatively little food of 

 the kind to which northern birds are accustomed, 

 and the northern states of Mexico are just about 

 as bare. 



**The Kentucky and Golden- winged Warblers 

 have a little route of their own and cut across from 

 the coast of Texas to northern Vera Cruz. But 

 one of the strangest things of all our migration 

 routes is that the shortest passage across the Gulf 

 — from Florida to Cuba and thence to Yucatan — 

 is almost deserted, save for a few Swallows and 

 shore birds. Western birds stay on the farther 

 side of the Rockies and only migrate down to the 

 middle of Mexico. 



