386 BULLliTIN 191, UNITED STATES NATIONAL MUSEUM 



Nesting. — The only nest of this species that I have seen was shown 

 to me by D. E. Brown near South Tacoma, on May 14, 1911, while we 

 were hunting through some of his favorite collecting grounds, smooth, 

 level land with a fine growtli of firs and cedars scattered about; the local 

 species of firs were most abundant and were growing to perfection in 

 the open stand, where they were well branched down to the ground. 

 The chickadee's nest was 5 feet from the ground in the trunk of a large 

 dead pine, in a cavity evidently excavated by the birds in the rotten 

 wood behind the bark; since it contained one fresh egg. it was nul 

 closely examined. 



The nests of the chestnut-backed chickadee have been placed at 

 widely varying heights, according to various observers, but all seem to 

 agree that most of the nests are less than 10 feet above ground. Thomas 

 D. Burleigh (1930) writes of the nests that he has found about Tacoma : 

 "The usual situation was in a fir stub, varying in height from a foot and 

 a half to nine feet from the ground, although one nest was twelve feet 

 from the ground in a knot hole in the trunk of a large dead oak at the 

 edge of a stretch of open prairie, while another was five feet from tlie 

 ground in a cavity in the thick bark of a large Douglas fir in a short 

 stretch of open woods." 



J. H. Bowles (1909) has published an excellent account of this chick- 

 adee, in which he says : 



At the approach of the nesting season the Chestnut-backs retire to the most arid 

 section of the country to be found, the more exposed it is to the sun the better, 

 and it is only in such locations that one may ever expect to find them during tlie 

 breeding season. The nesting site is chosen about the middle of April, most often 

 in the dead stub of some giant fir or oak. On one occasion only have I found the 

 nest near water, this being in a small willow on the edge of a swamp. 



The birds almost invariably dig their own hole, but I once found a nest in tlie 

 winter burrow of a Harris Woodpecker. One peculiarity about them, which 

 greatly increases the difficulty of finding their nests, is that they almost never start 

 the hole for themselves. Instead they select some place where a fragment of the 

 wood or bark has been split away, or else they will often take the oval hole made 

 by the larva of one of our largest beetles. These holes are not altered at the en- 

 trance in any way and, as the dead trees are full of them, it is extrenx'ly difficult 

 to locate the one containing the nest. 



He says that these chickadees sometimes nest in loose colonies; in 

 one locality he "found no less than seven occupied nests inside a very 

 small area, some not more than fifty yards apart." The lowest nest 

 he found was only "two feet up in a tiny fir stub," but he says that 

 "it is nothing unusual to find them fifty feet up in the giant fir stubs, 

 remnants of long past forest fires." Dawson (1923) says that he has 

 "found nests as high as eighty feet in a fir stub ; and in two instances 

 in a dead tree v.hollv surrounded bv water." 



