316 ANIMAL LIFE IN THE YO SEMITE 



Occurrence. — Eesident in moderate numbers throughout the region except in the 

 Lower Sonoran Zone and above timber line. Observed at Pleasant Valley and thence 

 eastward to vicinity of Mono Lake ; highest station of record^ Warren Fork of Leevining 

 Creek at 9300 feet altitude. Forages in more open stands of both coniferous and 

 deciduous trees. 



The Modoc Woodpecker is but a local race of the wide-ranging 'hairy' 

 woodpecker, which is found practically everywhere in the forested regions 

 of North America. As with most of the allied forms, the present race 

 ranges through several life zones, from the scattered digger pines at Pleas- 

 ant Valley eastward through the main forest belt to the sparse tracts of 

 Jeffrey pines in the vicinity of Mono Lake. It is nowhere really common, 

 even for a woodpecker; it reaches its greatest numbers in the upper part 

 of the Transition Zone and in the Canadian Zone. 



The Modoc Woodpecker is identical in pattern of coloration with the 

 much smaller Willow Woodpecker, save that the outer tail feathers of the 

 larger bird are pure white, whereas in the smaller species they are barred 

 with black. The special plumage features which are associated with 

 differences in sex and age are likewise identical in the two species. Adult 

 males have a narrow fringe of red feathers across the back of the head 

 (pi. 5/), whereas young males have the whole top of the head red. Adult 

 females entirely lack the red color and young females have only a few 

 scattered red feathers on the crown. 



A comparison of the weights of these two woodpeckers shows that the 

 Modoc is about two or three times as heavy as the Willow Woodpecker. 

 Thus, male Modoc Woodpeckers weigh on the average 68.1 grams (2.4 

 ounces) and females 58.9 (2.1 ounces), whereas Willow Woodpeckers weigh 

 27.0 (0.95) and 24.4 grams (0.86 ounces) respectively. The Nuttall Wood- 

 pecker, a Sonoran Zone species of similar build and proportions to the two 

 species just mentioned, weighs 41.2 (1.45) and 34.4 grams (1.2 ounces), 

 for the two sexes, respectively, being thus fairly intermediate. 



During the summer months we rarely saw in a morning's walk more 

 than one individual of the Modoc Woodpecker. But in Yosemite Valley, 

 during the winter season, the birds seemed as noisy and conspicuous as 

 they had been quiet and unobtruding before. Perhaps this impression was 

 enhanced by the absence of the voices of summer birds. One of our note- 

 book records (December 20, 1914) reads: 



Four seen in two and a half hours; the most noticeable bird, making enough noise 

 to give the impression of many. No ' ' rolling, ' ' but much tapping and frequent high- 

 pitched ' ' speenks ' ' ; birds working on dead limbs of tall cottonwoods and black oaks on 

 the Valley floor. 



The Modoc Woodpecker forages on both evergreen and deciduous 

 trees, favoring the latter, perhaps, during the winter months. In summer 

 it is usually rather quiet, particularly so as compared with the noisy Cali- 



