324 BULLETIN 191, UNITED STATES NATIONAL MUSEUM 



Dr. Samuel S. Dickey (MS.) says of the mating of the chickadee: 

 "From what 1 am able to learn of this process, the birds grow agitated 

 late in March and increase their vivacity during April and early in 

 May. They hurry between aisles of trees and swerve over bypaths, and 

 males dart at and even clasp one another. Then they part, and the 

 more dominant male pursues and chases a female over brush piles and 

 even to the ground. Then up they arise and hurry onward. A few 

 such days of immoderate activity, and their nuptial rites seem completed." 



Nesting. — The commonest nesting site of the chickadee is a hole, made 

 by the birds themselves, in a dead stub or branch of a gray birch. From 

 such a tree the decayed wood can easily be removed in dry chips to 

 form a cavity, and the ring of strong bark holds the branch firmly 

 together. 



Arthur C. Bent (MS.) says that in Bristol County, Mass., three- 

 quarters of the nests he has found have been in such a location, 4 to 8 

 feet from the ground. He continues: "Other nests have been in natural 

 cavities in apple trees in orchards, or in other deciduous trees. I be- 

 lieve that chickadees almost always, at least partially, excavate their own 

 nest cavities: I have seen them doing it; they cut through the outer 

 bark of birch stubs with their strong little bills and easily remove the 

 rotten wood from the interior." 



Edward H. Forbush (1912) states: 



A hole in a decayed birch stump, two or three feet from the ground, a knot- 

 hole in an old apple tree, in a fence-post, or in an elm, forty or fifty feet from 

 the ground, the old deserted home of some Woodpecker, a small milk-can nailed up 

 in a tree, or a nesting-box at some farmhouse window, may be selected by the 

 Chickadee for its home. Commonly it digs out a nest-hole in the decaying stump 

 of a birch or pine. It is unable to penetrate sound wood, as I have seen it 

 repeatedly try to enlarge a small hole in a white pine nesting-box, but it could 

 not start a chip. Often the Chickadee gains an entrance through the hard outer 

 coating of a post or stump into the decaying interior by choosing, as a vantage 

 point, a hole made by some woodpecker in search of a grub. The Chickadee 

 works industriously to deepen and enlarge this cavity, sometimes making a hole 

 nine or more inches deep; and the little bird is wise enough to carry the tell-tale 

 chips away and scatter them far and wide — something the Woodpeckers are less 

 careful about 



Sometimes the hole is excavated in the broken top of a leaning stump or tree, 

 and once I found one in the top of an erect white pine stump with no shelter 

 from the storm. 



If we come upon a pair of chickadees at work excavating a cavity, we 

 can step up very close to them and watch without interrupting them 

 at all. Both members of the pair work at the same time but visit the 

 nest alternately. Each one digs out a beakful of chips and flies away 

 with it, and no sooner is one gone than the other is back at the nest. 



