WOODPECKEBS 321 



of red across the back of the otherwise white head, but their mates lack 

 this coloring. In juvenile males the hinder half of the head is more or 

 less solidly red, and even in juvenile females there is usually a little red 

 in the same place. In late summer the feathers on top of the head in adult 

 birds may be so badly worn as to show the white much less clearly. 



The White-headed Woodpecker is not so promiscuous in its foraging as 

 are some other species, but gives most of its attention to live coniferous 

 trees. This probably accounts for the fact that the feathers on its throat 

 are almost always besmeared with pitch, whereas those of the Modoc Wood- 

 pecker, for instance, which lives in the same timber belt but forages 

 mostly in dead trees, are relatively clean. So far as we could determine 

 the foraging of this bird seems to be a rather haphazard proceeding. A 

 female near Tamarack Flat was watched for a considerable period of time 

 as she hunted over a number of trees. She would prospect one tree for a 

 while, but when it had been gone over only partially, she would go on to 

 inspect a second and then a third, with similar lack of thoroughness ; often 

 after examining portions of several trees the bird would return to one or 

 more of those previously visited. 



The usual call note of this woodpecker is a single wiek, but when 

 excited, the female calls cheep-eep-eep-eep, very fast, and repeats the call 

 every few seconds. The male, under similar circumstances calls yip, yip, 

 yip, yip, in a much shriller tone, but in slower time. 



Because of the striking appearance of the Northern White-headed 

 Woodpecker, and also because no special pains seem to be taken by the 

 birds to conceal their nesting sites, it is an easy matter to locate the nests. 

 In fact, nests of this species proved to be more easily located than those 

 of any other woodpecker in the Yosemite region. For this reason we shall 

 present some remarks upon the activities and ecologic relation>sliips of 

 woodpeckers in general while writing of this species. The matters here 

 discussed may be readily confirmed as to accuracy by anyone who will 

 watch a few pairs of these birds during the nesting season. 



To locate occupied nests the enquirer has merely to tap the bases of 

 stubs containing likely looking holes. If he merely passes by an occupied 

 tree, no bird appears, but upon his tapping on the bole, a scratching 

 sound within is followed shortly by the appearance of a white head framed 

 in the entrance of a hole. If the observer remains, the bird flushes and 

 quits the vicinity, but as it flies off one may usually see whether the back 

 of its head bears the red fringe of the male or the plain white of the 

 female. Our own experiences follow in some detail. 



The behavior of a pair seen near LeConte Memorial Lodge in Yosemite 

 Valley, on May 31, 1911, quickly led to the finding of a nest in a black 

 oak close at hand. On June 24, 1915, a female bird, flushing at our 



