20 BIRDS OF THE ROCKIES 



In this chapter attention will be called to a few 

 general facts relative to bird life in the Rockies, leav- 

 ing the details for subsequent recital. As might be 

 expected, the towering elevations influence the move- 

 ments of the feathered tenants of the district. There 

 is here what might be called a vertical migration, 

 aside from the usual pilgrimages north and south 

 which are known to the more level portions of North 

 America. The migratory journeys up and down the 

 mountains occur with a regularity that amounts to a 

 system ; yet so far as regards these movements each 

 species must be studied for itself, each having manners 

 that are all its own. 



In regions of a comparatively low altitude many 

 birds, as is well known, hie to the far North to find 

 the proper climatic conditions in which to rear their 

 broods and spend their summer vacation, some of them 

 going to the subarctic provinces and others beyond. 

 How different among the sublime heights of the 

 Rockies ! Here they are required to make a journey 

 of only a few miles, say from five to one hundred or 

 slightly more, according to the locality selected, up the 

 defiles and cafions or over the ridges, to find the con- 

 ditions as to temperature, food, nesting sites, etc., that 

 are precisely to their taste. The wind blowing down 

 to their haunts from the snowy summits carries on its 

 wings the same keenness and invigoration that they 



