104 BULLETIN 17 4, UNITED STATES NATIONAL MUSEUM 



feathered denizens of the woods. It is a well-known fact that wood- 

 peckers are most useful in guarding the living trees and destroying 

 the insect pests that injure them; but Grinnell and Storer (1924) 

 have called our attention to the fact that woodpeckers in general, and 

 the white-headed woodpecker in particular, contribute, by their ex- 

 cessive drilling of nest holes, "rather directly toward bringing down 

 the standing dead timber." They continue : 



DrDIing by woodpeckers results in an increase in the number of entrances 

 through which insects may get at the heart wood of a tree and thus hasten its 

 ultimate disintegration. Water, also, is thus afforded an easier entrance and 

 this hastens decay. Eventually each and every tree must yield its place in 

 the forest to seedlings. The woodpeckers hasten this process of replacement, 

 once the tree is dead. 



Many of the wood-inhabiting animals depend upon this woodpecker to furnish 

 them convenient nest holes or retreats. We have found mountain chickadees 

 and slender-billed nuthatches incubating their own eggs in holes drilled in 

 earlier years by the white-headed woodpecker ; a Sierra flying squirrel was 

 found occupying an old white-head's hole. Probably, tree-dwelling chipmunks 

 and perhaps California pigmy owls also occupy holes of this woodpecker. 



DISTBIBUTION 



Range. — Pacific coast of the United States; occurring rarely in 

 southern British Columbia; nonmigratory. 



The range of the white-headed woodpecker extends north to Wash- 

 ington (Methow Eiver and probably Fort Colville) ; and northern 

 Idaho (Fort Sherman). East to western Idaho (Fort Sherman and 

 Grange ville) ; eastern Oregon (Hurricane Creek, Powder River 

 Mountains, Anthony, and Camp Harney) ; western Nevada (Carson) ; 

 and eastern California (Bijou, Yosemite Valley, Pyramid Peak, San 

 Bernardino Mountains, and Cuyaniaca Mountains). South to south- 

 ern California (Cuyaniaca Mountains and Mount Pinos). West to the 

 western slopes of the Sierra Nevadas, Calif. (Mount Pinos, Bear 

 Valley, Fyffe, Butte Lal^e, and Mount Shasta) ; western Oregon 

 (Pinehurst, Foley Creek, and The Dalles) ; and western Washington 

 (Kalama, Cle Ehim, and Methow River). 



The species has been separated into two subspecies, the northern 

 white-headed woodpecker {Dryohates a. alholarvatus)^ occupying 

 most of the range south to the southern end of the Sierra Nevadas, 

 and the southern white-headed woodpecker {D. a. gravirostris) , found 

 in the mountain ranges of southern California. 



Casual records. — A specimen collected near Point Bonita, Marin 

 County, Calif., on July 20, 1932, is the only coastal record in that State. 

 There is, however, an old record for Grays Harbor, Wash, (previous 

 to 1892) , which cannot now be confirmed. 



In the Provincial Museum at Victoria, British Columbia, there is 

 an unlabeled specimen said to have been collected in the Similkameen 



