54 -¢ Ve Vol. XXIV 
A, STUDY OF ROOSTING HOLES OF THE RED-SHAFTED FLICKER 
By EMERSON A. STONER 
WITH THREE ILLUSTRATIONS 
N A FAR CORNER of the cemetery in Benicia, California, is a small shack, 
fourteen by twenty feet, built of redwood and called the ‘‘pest house’’, for 
~ the reason that at infrequent intervals some case of small pox is quaran- 
tined therein. For several years there has been no occupant, and because the 
building is not often approached it has resulted that the walls on each of its 
four sides have been disfigured by the characteristic roosting holes drilled 
through the one-inch boards by Red-shafted Flickers (Colaptes ca/er collaris). 
At the present time there are seven large holes completed or of sufficient size 
to allow the entrance of the birds, and in addition there are nine smaller exca- 
vations the completion of which the birds have either postponed or abandoned. 
: This is not the only building so perforated by flickers in Benicia, but it 
may be cited to illustrate this characteristic habit of the western bird, a trait 
not often shared by the flicker of the eastern states. 
Fig. 25, ‘“Prst HOUSE’, BENICIA, CALIFORNIA, USED AS A BUNK HOUSE 
BY RED-SHAFTED FLICKERS. 
The common impression of the casual passer-by seems to be that these ex-— 
cavations are made by some woodpecker for nesting purposes. However, it is 
very evident that they have no connection with nidification, but that the prim- 
ary object of these excavations is to provide sleeping quarters. I am inclined 
to believe that there is also at times an element of drilling simply ‘‘for the fun 
of it’’; especially does this seem to be the case when a number of holes are 
made in close proximity to each other and lead to practically the same point 
in the interior. 
Any one of the holes in the building referred to above allows access to the 
entire interior, which is unlighted except through the excavations made by 
the bird. From his entrance he may get a ‘‘bird’s-eye view’’ of a few pieces of 
