364 BULLHTIN 191, UNITED STATES NATIONAL MUSEUM 



with almost anywhere in the forested mountains. In Santa Qara 

 Canyon, where we found them in the oaks, nut pines, and junipers of 

 the south slope, down along the creek, in the turns where the sun came 

 in, they were in the alders and birches together with migrating warblers, 

 vireos, and flycatchers. But they are found in the high, dark, conif- 

 erous forests as well, and it is here that their cheery notes are most 

 gratefully heard." 



In his paper on the subspecies of the mountain chickadee, Dr. Joseph 

 Grinnell (1918) says: "Among the four subspecies of Penthestes 

 gamheli here recpgnized, color alone is sufficient for distinguishing P. 

 gamheli gamheli. The flanks, sides of body and back in this form are 

 pervaded with a distinct tinge of cinnamon — more exactly, the 'pinkish 

 buflF' of Ridgway (1912, pi. 29). In addition, this race shows the great- 

 est length of tail, and slenderest bill," 



Nesting. — The mountain chickadee does not seem to be at all par- 

 ticular about the choice or location of its nest. It prefers, however, to 

 place its nest in a natural cavity in a tree, or in an old woodpecker 

 hole, and I believe that it does not excavate its own nest c.avity if it 

 can find one already made for it. Its nest has been found at heights 

 ranging from 2 to 80 feet above the ground, the extreme heights being 

 very rare; apparently very few nests are more than 15 feet from the 

 groimd, and many are less than 6 feet up. J. K. Jensen (1923) says 

 that, in New Mexico, he often finds this chickadee nesting in bird boxes, 

 and he has "found the nests in cavities in pine stumps, in quaking aspens 

 and under rocks." Later (1925) he writes: 



"May 15, 1925, I made a trip ten miles southeast of Santa Fe in- 

 tending to examine a number of bird boxes. One of the boxes con- 

 tained a set of six eggs of the Mountain Chicadee (Penthestes gambeli 

 gamheli) and three eggs of the Gray Titmouse (Baeolophus inornatus 

 griseus) with the Chicadee incubating. I took out the six eggs of the 

 Chicadee and left those of the Titmouse. May 22, the Chicadee was 

 incubating four Titmouse eggs, all of which hatcjied. June 8, I again 

 visited the box and found the Chicadee busy feeding four young 

 Titmice." 



This chickadee is a very close sitter, reluctant to leave its nest, 

 and it has developed to a very high degree the intimidation reaction to 

 the approach of an intruder, a habit shared by other species of chickadee. 

 This consists of a loud hissing noise and a rapid fluttering of the 

 wings, when the nest is invaded; it might be enough to frighten away 

 some smaller enemy, but to man it serves only to illustrate the devotion 

 of the brave little bird to its eggs or young; the heartless egg collector 

 seldom rewards the devoted mother for her bravery. 



