10 
FARMERS BULLETIN 630. 
Fig. 9.—Song sparrow. Length, about 
Qh inches. 
cent) is eaten in June, when the larger species are still young and the smaller 
most numerous. Besides the insects already mentioned, many wasps and bugs 
are taken. Predacious and parasitic bymenopterous insects and predacious 
beetles, all useful, are eaten only to a slight extent, so that as a whole the insect 
diet of the native sparrows may be considered beneficial. There are several 
records of potato-bug larvae eaten by chipping sparrow’s. 
Their vegetable food is limited almost 
exclusively to hard seeds. This might 
seem to indicate that the birds feed to 
some extent upon grain, but the stom¬ 
achs examined show only one kind, oats, 
and but little of that. The great bulk 
of the food is made up of grass and 
weed seed, which form almost the entire 
diet during winter, and the amount 
consumed is immense. 
In the agricultural region of the up¬ 
per Mississippi Valley, by roadsides, on 
borders of cultivated fields, or in aban¬ 
doned fields, wherever they can obtain a 
foothold, masses of rank weeds spring 
up and often form almost impenetrable 
thickets which afford food and shelter 
for immense numbers of birds and 
enable them to withstand great cold and the most terrible blizzards. A person 
visiting one of these weed patches on a sunny morning in January, when the 
thermometer is 20° or more below zero, will be struck with the life and anima¬ 
tion of the busy little inhabitants. Instead of sitting forlorn and half frozen, 
they may be seen flitting from branch to branch, twittering and fluttering, and 
showing every evidence of enjoyment and perfect comfort. If one of them is 
captured it will be found in excellent condition; in fact, a veritable ball of fat. 
The snowbird 1 and tree sparrow 2 are 
perhaps the most numerous of all the 
sparrows. Examination of many stom¬ 
achs shows that in winter the tree spar¬ 
row feeds entirely upon seeds of weeds. 
ITobably each bird consumes about one- 
fourth of an ounce a day. In an arti¬ 
cle contributed in 1SS1 to the New York 
Tribune the writer estimated the amount 
of weed seed annually destroyed by 
these birds in Iowa. On the basis of 
one-fourth of ail ounce of seed eaten 
daily by each bird, and an average of 
ten birds to each square mile, remain¬ 
ing in their winter range 200 days, there 
would be a total of 1,750,000 pounds, 
or 875 tons of weed seed consumed in 
a single season by this one species. 
Large as are these figures, they unques¬ 
tionably fall far short of the reality. 
The estimate of 10 birds to a square 
mile is very conservative, for in Massa¬ 
chusetts, where the food supply is 
less than in the Western States, the tree 
sparrow is even more abundant than 
this in winter. The writer has known 
places in Iowa where several thousand tree sparrows could be seen within the 
space of a few acres. This estimate, moreover, is for a single species, while, 
as a matter of fact, there are at least half a dozen birds (not all sparrows) that 
habitually feed during winter on these seeds. Farther south the tree sparrow 
is replaced in winter by the white-throated sparrow, 3 the white-crowned spar¬ 
row, 4 the fox sparrow, 6 the song sparrow, the field sparrow, and several others; 
Fig. 10.—Field sparrow. Length, about 
55 inches. 
1 Jnnco hy emails. 
2 Spisella monticola. 
5 Passerella iliaca. 
3 Zonotrichia alhicollis. 
4 Zonotrichia leucophrys. 
