[6] BIRDS OF OREGON 



Woodpecker, expresses the very spirit of the untamed mountains; and the 

 ringing laugh of the loon, still heard on some coastal and mountain lakes, 

 is one of the most thrilling sounds in the Oregon out-of-doors. There are 

 few whose imagination is not stimulated by the strident cries of the 

 V-shaped flocks of wild geese passing far overhead or by the trumpet calls 

 of the Sandhill Cranes that continue to float back to earth long after the 

 circling flocks have passed from sight into the heavens. 



NEST BUILDING 



THE NEST-BUILDING habit of birds still arouses a great deal of popular 

 interest. The nests may vary from none at all to the complicated apart- 

 ment-house structures built by the weaver finches of Africa. Among the 

 birds that build no nests are many shore birds that lay their eggs on the 

 open ground or in shallow depressions, possibly lined with a few bits of 

 vegetation or small pebbles; the nighthawks that deposit their two eggs 

 either on the ground or on the roofs of buildings in cities; and the seafowl, 

 such as murres, that select bare ledges of rock on precipitous cliffs for 

 their eggs, which, sharply pointed at one end, roll around and around on 

 the sharp point and thus often are prevented from being blown or knocked 

 from the cliffs. 



Many nesting habits have been developed apparently independently in 

 many sections of bird families. Birds from such widely separated families 

 as kingfishers, petrels, auklets, puffins, and Bank and Rough-winged 

 Swallows nest in burrows in the ground, while in North Portland and a 

 few other localities in Oregon the Red-shafted Flickers, despite the 

 abundance of trees to furnish normal nesting sites, have abandoned their 

 traditional wooden apartment houses for holes excavated in clay banks. 



Holes in trees are popular nesting sites with birds. Birds of the wood- 

 pecker and nuthatch families do their own construction work, the wood- 

 peckers being equipped with up-to-date wood-working tools that are 

 especially developed for collecting wood-boring insects and excavating 

 holes for nest sites. Many other species of birds later appropriate the 

 abandoned woodpecker holes or make use of natural cavities in the trees. 

 In Oregon, such widely varied species as owls, hawks, chickadees, blue- 

 birds, tree swallows, and wood ducks are regular tenants of such structures. 



Many small birds nest on the ground, building more or less complicated 

 structures in which to lay their eggs. Numerous sparrows and warblers 

 belong in this class, weaving cup-shaped nests in shallow depressions in 

 the ground. Many ducks do likewise, covering the eggs with down 

 plucked from their own breasts. A great variety of other birds occa- 

 sionally or habitually build ground nests. 



Most of the more familiar birds, however, build structures of one kind 

 or another, in trees, in bushes, or even in herbaceous plants. They may 



