OUR WINTER BIRDS IN THEIR FOOD RELATIONS. 
79 
during November, Decem- 
ber, January, February, and 
March. The results as a 
whole show that more than 
half of the food of the chick- 
adee during the winter 
months consists of insects, 
a very large proportion* of 
these being taken in the 
form of eggs. Abont five 
per cent, of the stomach 
contents consisted of spiders 
or their eggs. Vegetation 
of various sorts made up a 
little less than a quarter of 
the food, two thirds of which, 
however, consisted of buds 
and bud scales that were 
believed to have been acci- 
dentally introduced along 
with plant-lice eggs. These 
eggs made up more than 
one fifth of the entire food, 
and formed the most re- 
markable element of the 
bill of fare. It seems to 
me evident that a large pro- 
portion of the bud scales 
are accidentally introduced 
into the stomachs of the 
birds, because most of the 
aphid eggs are taken from 
the crevices beside the buds 
of deciduous trees and 
shrubs; and so it must 
commonly happen that bud 
scales are pecked away and 
swallowed with the eggs. 
This destruction of the 
myriad eggs of plant-lice 
that infest fruit, shade, and 
forest trees is probably the 
most important service 
which the chickadee ren- 
ders during its winter resi- 
dence. More than 450 eggs 
Eggs of 
Aphides 
about buds 
of birch. 
The Chickadee or Black-Capped Titmouse. 
sometimes occur as the food of one 
bird in a single day. On the supposi- 
tion that one hundred were eaten daily 
by each of a flock of ten chickadees, 
there would be destroyed 1,000 a day 
or 100,000 during the days of winter, 
a number which I believe to be far 
below the real condition, could we 
determine it precisely. 
Insect eggs of many other kinds 
were found in the food of the chicka- 
dees. Many of these it was impossi- 
ble to recognize, but there was no 
difficulty in identifying the eggs of 
the common American Tent Cater- 
pillar and the Fall Cankerworm. 
There were also present the eggs 
and egg sacs of many spiders of 
kinds commonly occurring under 
loose bark. While spiders as a class 
are doubtless beneficial creatures, 
the destruction of some of them is 
not, in my opinion, to be considered 
as detrimental to the usefulness of 
the chickadee. The larvae of seve- 
ral different kinds of moths were 
also found. One of the most abun- 
dant species was believed to be the 
common apple worm, the larva of 
