A FAMILY OF TREE SWALLOWS 



(Iridoprocne bicolor) 



THE tree swallow is one of the many 

 birds that nest at high altitude in the 

 Wasatch Mountains. The favorite 

 nesting places of these square-tailed gleaners 

 of the air are old sapsuckers' holes, and in 

 suitable clusters of mountain ash trees, they 

 often nest in colonies of several dozen pairs. 



The situation of their nests puts a difficulty 

 in the way of photographing them. I found, 

 however, a nest in an ash that was close to an- 

 other ash; the accompanying picture explains 

 the method by which photographs were se- 

 cured. Cross pieces nailed one above the 

 other furnished a ladder up the unoccupied 

 tree, and a slab nailed at the proper height 

 pointing directly at the nest hole served as a 



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