ECONOMIC RELATIONS OF OUR BIRDS. 
453 
tries has led to much of the diversity of opinion in regard to the value of birds 
as destroyers of insei’ts, and to much of their needless persecution. The Bobo¬ 
link, considered with reference to rice-culture, has been regarded as a scourge 
in the Carolinas, where almost countless numbers of them have been slaughtered. 
But all through the Northern States, where it spends the summer, and where it 
is almost exclusively insectivoi’ous, few birds are more needed than it. Here it 
occupies the grassy meadows, both damp and dry, where grasshoppers, crickets, 
cutworms, and other noxious insects abound and upon which it may feed. To 
the dairying interests of its sumnrer home, then — and these are by far the 
greater and more important — it is as beneficial as it is destructive to the rice- 
crops of the South. Shall we ask our Southern friends to guard their irlanta- 
tions aird spare the birds ? Before we can do this with consistency we must 
know more definitely than we do now what injury and service they render in the 
South, what work they do in the West Indies, whither they take themselves for 
the winter, and what is to be the mission of the large number that pass by us 
in summer to the fast opening Saskatchewan country to breed. 
(3) The food and habits of the bird in different localities. That these ele¬ 
ments must be taken into consideration is sufficiently evident from what has 
been said in regard to the Bobolink under the last head. 
(3) The food of the bird daring different seasons. There are very many of 
our birds which, if judged alone by their food during a particular season, would 
be classed as injurious, when in reality they are very beneficial. The Red¬ 
winged Blackbird during the month of August is, in many localities in Wiscon¬ 
sin, very injurious, and for this reason has often been declared a nuisance. It 
is, however, far from being such. During the months of May, June and July, 
its home is in the sloughs, wet meadows and low jjastures, and from these it 
often visits the adjoining dry fields. In all of these places it feeds, like the 
Bobolink, very largely upon insects. After the corn has hardened in the fall, it 
is again beneficial, feeding almost exclusively upon insects and the seeds of 
weeds, which it obtains in cultivated fields. 
(4) The food of the bird when young and ivhen mature. We probably have 
no bird except the Carolina Dove, Passenger Pigeon, possibly the Thistle Bird, 
and perhaps some of the birds of prey, whose young are not largely or entirely 
fed u])on insects. The first few weeks of a bird’s life (during which time the 
majority of our species attain their full size) is the most voracious period of its 
existence. Dr. Bradley has estimated that a pair of Sparrows, with a brood to 
feed, will consume 3,3G0 caterpillars in the course of a week. A pair of Thrushes 
are said to have carried to their young, in the course of an hour, 100 insects, 
principally caterpillars. A young Robin, reared by Prof. Treadwell, required 
not less than sixty earth-worms a day. A Wood Pewee was observed by the 
writer to carry, to her brood of three, forty-one insects in three-fourths of an 
hour. 
In view of these facts, it is evident that there can be but few of our birds, 
unless it be some of those which plunder the nests of other birds, which are not 
beneficial during one period of their existence at least. 
(5) When and how long the bird is with us. The birds that are with us longest, 
other things being equal, are, of course, capable of rendering the greatest serv¬ 
ice or the greatest injur}^ and they are tlie birds, viewed from an economic 
standpoint, wliich should interest us most. But the service which birds of pas¬ 
sage render is far from being so insignificant as to be overlooked. On the con¬ 
trary, the services of these birds are so great that we have a right to demand 
their protection when tlie^ are in lands not our own. 
