2 
FARMERS* BULLETIN 630. 
season and are able to maintain bike by eating vegetable food, as the seeds of 
weeds. Here again is another useful function of birds in destroying these weed 
seeds and thereby lessenihg the growih of the next year. 
In the following pages are discussed the food habits of more than 50 birds 
belonging to 12 families. Many are eastern forms which are represented in 
the West by slightly different species or subspecies, but unless the food habits 
differ they are not separately described. In some cases specific percentages of 
food are given, but for the most part the statements are made without direct 
leference to the data on which they are based. 1 
The parts of this bulletin relating to the crow and blue jay were contributed 
by E. R. Kalmbach, and the discussion of the nighthawk is by W. L. McAtee, 
both of the Bureau of Biological Survey. 
THE BLUEBIRDS. 
The eastern bluebird 2 (fig. 1), one of the most familiar and welcome of our 
feathered visitors, is a common inhabitant of all the States east of the Rocky 
Mountains from the Gulf of Mexico to southern Canada. In the Mississippi 
Valley it winters as far north as southern Illinois, and in the East as far as 
Pennsylvania. It is one of the earliest northern migrants, and everywhere is 
hailed" as a harbinger of spring. Very domestic in habits, it frequents orchards 
and gardens, and builds its nests in 
cavities of trees, crannies in farm 
buildings, or boxes provided for its 
use. 
The bluebird has not been ac¬ 
cused, so far as known, of stealing 
fruit or of preying upon crops. An 
examination of 855 stomachs showed 
that 68 per cent of the food consists 
of .insects and their allies, while the 
other ,32 per cent is made up of 
various vegetable substances, found 
mostly in stomachs taken in winter. 
Beetles constitute 21 per cent of the 
whole food, grasshoppers 22, cater¬ 
pillars 10, and various other insects 
9, while a number of spiders and 
myriapods, about 6 per cent, com¬ 
prise the remainder of the animal 
diet. All these are more or less 
harmful, except a few predacious beetles, which amount to 9 per cent. In view 
of the large consumption of grasshoppers and caterpillars we may at least con¬ 
done this offense, if such it may be called. The destruction of grasshoppers is 
very noticeable in August and September, when these insects make up about 53 
per cent of the diet. 
It is evident that in the selection of its food the bluebird is governed more 
by abundance than by choice. Predacious beetles are eaten in spring, as they 
are among the first insects to appear; but in early summer caterpillars form an 
important part of the diet, and these are later replaced by grasshoppers. Beetles 
are eaten at all times, except when grasshoppers are more easily obtained. 
1 Farmers’ Bulletins describing the food habits of wild birds and groups of birds, or 
presenting methods of attracting them about our homes have been issued as follows : 
54. Some Common Birds in their Relation to Agriculture, by F. E. L. Beal, 1897. The 
present bulletin is largely a revision of this bulletin and supersedes it. 
383. How to Destroy English Sparrows, by Ned Dearborn, 1910. This bulletin has 
been superseded by Farmers’ Bulletin 493. 
450. Our Grosbeaks and Their Relation to Agriculture, by W. L. McAtee, 1911. 
493. The English Sparrow as a Pest, by Ned Dearborn, 1912. 
497. Some Common Game, Aquatic, and Rapacious Birds in Relation to Man, by W. L. 
McAtee and F. E. L. Beal, 1912. 
500. Food of Some Well-known Birds of Forest, Farm, and Garden, by F. E. L. Beal 
and W. L. McAtee, 1912. 
513. Fifty Common Birds of Farm and Orchard, prepared under the direction of Henry 
W. Ilenshaw, 1913. This bulletin was issued with illustrations in color, and the demand 
for it was so enormous that it is no longer available for free distribution. Copies may 
be had for 15 cents (postage stamps not accepted) of the Superintendent of Documents, 
Government Printing Office. 
009. Bird Houses and How to Build Them, by Ned Dearborn, 1914. 
621. How to Attract Birds in Northeastern United States, by W. L. McAtee, 1914. 
2 Sialia sialis. 
