July, 1921 STORAGE OF ACORNS BY THE CALIFORNIA WOODPECKER 111 
of which were acorns; in the rest were bits of granite gravel of size corre- 
_ sponding with the acorns in the other holes. This was unmistakably the work 
ef our woodpecker, and the unusual percentage of stones would seem to indi- 
cate either the work of years or to point to several recent bad acorn seasons. 
‘ It is interesting to note that the habit of this woodpecker of storing food 
is not confined to the temperate zone but accompanies the species to its trop- 
ical habitat where food abounds and there would seem to be no adequate rea- 
son for it. Thus it is stated in the Proceedings of the Zoological Society (p. 
14, 1876), that Mr. O. Salvin exhibited and made remarks on the section of the 
trunk of a pine from Guatemala perforated by a woodpecker (Melanerpes 
formicivorus) ‘‘for the purpose of storing acorns’’. 
De Saussure* also states that in the desert near Cafre de Perote, Vera Cruz, 
Mexico, Colaptes cafer |Red-shafted Woodpecker] bores holes into dead agave 
stalks through which it inserts acorns into the hollow interior of the stalk. 
The birds begin the holes near the bottom and fill up the entire stalk. The 
storing of this food for consumption later in the winter must be important in 
woodpecker eyes, since the acorns were brought from a considerable distance 
from the mountains where alone the oaks grow. This account tallies so weil 
with the habits of the California Woodpecker and is so unlike the known hab- 
its of Colapies that I am led to raise the question whether or not the bird was 
that species and not the red-shafted one. At all events the birds were wood- 
peckers, and they appear to have hit upon a safe place of deposit which argues 
well for their intelligence. 
While I do not doubt that the acorn-storing habit is based on the more 
or less definite intent to provide food for future use, the faulty methods em- 
ployed and the imperfect results obtained show that as yet the birds have only 
imperfectly learned their lesson. Thus when the acorn season arrives the birds 
do not systematically proceed to fill all the available holes and then make 
others as needed, but dig holes at any and all seasons as they have leisure or 
feel inclined. The result is that the supply of holes in a locality usually far 
exceeds the number of acorns stored, with a corresponding waste of energy 
and lack of foresight. | 
In searching for the motives underlying the storing habit of the Califor- 
nia Woodpecker we should not lose sight of the fact that the several acts in — 
the process, the boring of the holes, the search for the acorns, the carrying 
them to the holes and the fitting them in, bear no semblance to work in the ordi- 
nary sense ot the term, but is play. I have seen the birds storing acorns many 
times, and always when thus engaged they fill the air with their joyous eries 
and constantly play tag with each other as they fly back and forth. When 
thus engaged they might not inaptly be likened to a group of children at play. 
In further illustration of the play habit of this woodpecker it is to be 
noted that its bill, as in the case of others of its tribe, is wonderfully well 
adapted to digging into wood, and it is as natural for the bird in its idle mo- 
ments to dig just for the fun of it as it is for the boy to whistle or the proverb- 
ial Yankee to whittle a stick.- I have many times observed the Downy and the 
Hairy Woodpecker drilling holes in sound trees with no apparent purpose 
unless 10 occupy an idle moment. I have also noticed in Maine live fir trees in 
the trunks of which several inches of bark and wood had been dug out by the 
ee eS eee 
*Observations sur les Moeurs de Divers Oiseaux des Mexique, 1858. 
