HOW BIRDS AFFECT THE ORCHARD. 
base, then running spirally upward, and, after a hurried inspection, 
winging its way to the next tree. These three birds perform a service 
which it is difficult for man to do for himself, and they should be 
protected and encouraged. 
CUCKOOS. 
Probably no group of insects contains a greater number of orchard 
pests than the order Lepidoptera, which comprises butterfliesand moths, 
with their larve, or caterpillars. Tent caterpillars, cankerworms, 
fall webworms, tussock moths, codling moths, and a host of others are 
among the worst enemies of the fruit grower. It is, therefore, fortu- 
nate that there are in the United States two birds that subsist, to a great 
extent, upon caterpillars, apparently preferring them to any other food. 
These are the cuckoos, the yellow-billed (Coccyzus americanus) and the 
black-billed (C. erythrophthalmus). For years it has been a matter of 
common observation that these birds feed largely on caterpillars, but, 
until a number of stomachs had been examined, it was not known how 
great a proportion of their food is made up of these harmful insects. 
The examinations indicated that caterpillars of various species, includ- 
ing some of the most destructive, constitute more than 48 per cent of 
their food. One stomach contained at least 250 tent caterpillars, 
probably a whole colony, in the young stage. In another 217 heads 
of the fall webworm (Hyphantria cunea) were counted, and this prob- 
ably fell far short of the real number, as these larvee are very small, 
and in many instances nothing but jaws remained undigested. In the 
stomachs of 155 cuckoos taken in various parts of the country were 
found 2,771 caterpillars of various species, or an average of 18 to each 
stomach. When we consider that a caterpillar is so soft and easily 
digested that soon after being swallowed it has entirely passed from 
the stomach, it is evident that in one day far more than this number 
(18) must have been eaten by the average bird. Many caterpillars are 
protected from the attacks of birds and parasitic insects by a covering 
of hair, and hairy caterpillars are only rarely eaten by most birds. 
Cuckoos, however, seem to prefer them to the smooth kind, and 
apparently eat them whenever they can be found. Caterpillar hairs 
are often stiff, bristly, and sharp at the end, like minute thorns, and it 
frequently happens that when a cuckoo’s stomach is opened and 
emptied it is found to be completely furred on the inside by hairs 
which have pierced the inner lining and become fast. Cuckoos eat 
many noxious insects besides caterpillars, such as beetles, bugs, and 
grasshoppers. Unfortunately, they are naturally rather shy birds, 
preferring the edges of woodland and groves to the more open cul- 
tivated grounds and orchards. If, however, they are unmolested, they 
soon gain confidence, and in many cases frequent shade trees about 
houses and lawns, or even in the very heart of the city. 
A1900——20 
