414 BULLETIN 191, UNITED STATES NATIONAL MUSEUM 



Nesting. — The birds that Dr. Price studied all nested in bird boxes; 

 evidently they prefer to nest in boxes where these are available. Sixty- 

 four adults were caught in the boxes and banded; there were 33 cases 

 of adults renesting in the same box (a bird nesting in the same box 

 for three years would be two cases of renesting) ; there were 17 cases 

 of adults nesting in boxes from 43 to 90 yards away, which were prac- 

 tically in the same territory ; there was only one case of nesting in a box 

 200 yards away, and none at a greater distanc.e. "If the changing of 

 nest-boxes were really a change of nesting territory one would expect 

 that the former territory would be taken over by another pair of 

 titmouses nesting in the first box. With the exception of tlie female 

 that moved 200 yards, this never took place. The first box was- 

 always either empty or used by bluebirds or chickadees. Often a bird 

 would alternate between two boxes from year to year." 



The plain titmouse normally nests in holes in trees, either old wood- 

 pecker holes or natural cavities in the trunks or limbs of trees, often 

 partially excavated by the birds in soft or rotten wood. Dawson (1923) 

 says it is a mistake to think that this bird cannot excavate its own 

 nest, and says: 



'"Two of the nests I have found (and not rifled) were excavated in 

 the heart wood of live limbs of the blue oak (Qnercus douglasi), not less 

 than ten inches in diameter. * * * I once trac,ed a Plain Titmouse to 

 a hole about twenty feet up in one of those cliffs of mingled gravel and 

 Vlobe' which line the banks of the San Jacinto River. * * * We found 

 a neat, round aperture in the earth, which must have been barely large 

 enough to admit the bird, being, in fact, so snug that it showed two 

 separate 'scores' for the feet. This opened rapidly into an ample 

 chamber with extensive inner recesses — a monument of toil. The nest 

 proper, a great bed of rabbit-fur, was placed about one foot from the 

 entrance." 



Grinnell and Storer (1924), referring lo the Yosemite region, say that 

 "old woodpecker holes are used when available, but many, perhaps a 

 majority, of nests are placed in naturally rotted-out cavities." The 

 height from the ground varies according to the location of these cavities ; 

 one of their nests was only 33 inches and another 10}4 feet from the 

 ground; I have seen one tliat was 32 feet aloft, which is probably un- 

 usual. One of their nests was only 17 inches from a western bluebird's 

 nest; it was "in a natural cavity of rather large size. The bottom held 

 a mass of fine dry grasses, perhaps 4 inches in depth, and on top of this 

 was a heavy felted lining of cow hair and rabbit fur. The top of this 

 mat was 5>4 inches * * * below the margin of the entrance." A nest 



