12 Bird -Lore 



not only on sanctuaries but elsewhere, as, for instance, in converting many 

 thousands of boys from bird-destroyers to bird-protectors. What degree of 

 suppression of forces inimical to bird-Hfe is thus occasioned we cannot know 

 with exactness, but it must be very great. It is easily conceivable that the 

 quantity of insects and weed seed consumed by the birds thus preserved is at 

 least as great as any increase of these pests arising through feeding the birds. 



Finally, the young birds raised on sanctuaries, public and private, are not 

 fed from the food-shelf while they are in the nest. They require a diet of soft- 

 bodied insects, which the parents must supply. The more young, the more 

 insects. If four broods are raised where formerly but one was the rule, four 

 times as many insects will be required for the purpose. This necessity of secur- 

 ing insects for the young will of itself prevent birds from incurring any grave 

 danger of being pauperized, and the greater quantity of insects needed for the 

 larger number of broods will obviate any diminution in the service to agri- 

 culture. 



To this point the argument has been of an a priori character. But a post- 

 eriori conclusion may be drawn from three facts, one general, the other two 

 specific. The general fact is that on sanctuaries, not only do the plants (in- 

 cluding trees) show no deterioration from insect attack, but they seem to be 

 healthier and freer from such depredations than before the feeding of birds 

 was begun. It is largely for the purpose of benefiting the plant-life on estates 

 that sanctuaries are established. The specific facts are as follows: When, a 

 few years ago, E. H. Forbush, State Ornithologist of Massachusetts, increased 

 the number of birds in his orchard by the usual means, his little pensioners, 

 the following summer, saved his fruit crop (and, incidentally, that of his next 

 neighbor) from the attacks of a host of tent caterpillars and cankerworms that 

 ruined every other fruit crop in the region. Again, when a similar outbreak of 

 caterpillars stripped the trees of a large area in Germany so bare that the 

 summer woods resembled those of winter, the birds that Baron Berlepsch had 

 fed and housed so protected his estate that although it stood in the midst of 

 the devastated area the invading army could not get within a quarter of a 

 mile of it. These examples of the actual effect of sanctuary methods amply 

 support the theoretical conclusions previously reached. 



We may, therefore, reassure ourselves and continue to enjoy our new in- 

 timacy with the birds with clear consciences. We shall not pauperize the 

 birds by our liberality and friendliness. On the contrary, we may rest with 

 confidence in the pleasant thought that, while instituting a delightful relation- 

 ship with our welcome guests and filling our homes with the added beauty of 

 their song and plumage we are increasing their general efiiciency and so in- 

 suring a greater degree of health and beauty to our lawns, trees, shrubs, and 

 flowers. 



