CHILDREN'S GARDENS 



greatest economic importance. The service ren- 

 dered by birds is greatest when they are rearing 

 their young. Most birds that feed upon fruit 

 and seeds feed their young on insects. Nestlings 

 can not digest hard substances, such as beetles 

 and hard seeds, and their food must consist of 

 soft-bodied insects, as caterpillars and other 

 larvae, grasshoppers, and spiders. The first week 

 the young are fed almost entirely upon cater- 

 pillars and spiders. The food of nestlings has 

 not been sufficiently understood, and the amount 

 consumed not generally appreciated. The num- 

 ber of broods varies with species and regions. 

 There is an average of two or three broods, of 

 three to five each, in a season. Nestlings demand 

 most constant and untiring industry on the part 

 of their parents. They consume more than their 

 own weight in a day, and make a daily gain in 

 weight of twenty to fifty per cent. They are 

 nearly all mouth and stomach, and spend almost 

 all their waking hours in eating. It has been 

 recorded that a robin ate sixty earthworms in a 

 day. The kind and quantity of food of the dif- 

 ferent nestlings is of great importance, since 

 many nests are placed in proximity to gardens, 

 and the nestling season corresponds to the pe- 

 riod when the depredation of insects is most 

 destructive. 



It has been found that the species of birds 

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