SOME COMMON BIRDS IN THEIR RELATION 
TO AGRICULTURE. 
INTRODUCTION. 
It has long been known that birds play an important part in relation 
to agriculture, but there seems to be a tendency to dwell on the harm 
they do rather than on the good. Whether a bird is injurious or bene- 
ficial depends almost entirely upon what it eats, and in the case of 
species which are unusually abundant or which depend in part upon the 
farmer’s crops for subsistence the character of the food often becomes a 
very practical question. If crows or blackbirds are seen in numbers 
about cornfields, or if woodpeckers are noticed at work in an orchard, it 
is perhaps not surprising that they are accused of doing harm. Careful 
investigation, however, often shows that they are actually destroying 
noxious insects, and also that even those which do harm at one season 
may compensate for it by eating noxious species at another. Insects 
are eaten at all times by the majority of land birds, and during the 
breeding season most kinds subsist largely and rear their young exclu- 
sively on this food. When insects are unusuaily plentiful, they are 
eaten by many birds which ordinarily do not touch them. Even birds 
of prey resort to this diet, and when insects are more easily obtained 
than other fare, the smaller hawks and owls live on them almost entirely. 
This was well illustrated during the recent plague of Rocky Mountain 
locusts in the Western States, when it was found that locusts were 
eaten by nearly every bird in the region, and that they formed almost 
the entire food of a large majority of the species. 
Within certain limits, birds feed upon the kind of food that is most 
accessible. Thus, as a rule, insectivorous birds eat the insects that are 
most easily obtained, provided they do not have some peculiarly dis- 
agreeable property. It is not probable that a bird habitually passes by 
oue kind of insect to look for another which is more appetizing, and 
there seems little evidence in support of the theory that the selection 
of food is restricted to any particular species of insect, for it is evi- 
dent that a bird eats those which by its own method of seeking are 
most easily obtained. Thus, a ground-feeding bird eats those it finds 
among the dead leaves and grass; a flycatcher, watching for its prey 
from some vantage point, captures entirely different kinds; and the 
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