The Audubon Societies 129 



Tanager, Red-eyed Vireo, Black and White Warbler, and other species, 

 attack these pests and devour them. Forbush says: "As time goes on, it is 

 probable that birds will become more and more efficient enemies of the gipsy- 

 moth and the brown-tail moth, as they learn better how to manage them. . . . 

 As the gipsy-moth spends more than half of the year in the egg, this is its most 

 vulnerable point. If Jays, Creepers, Nuthatches, Woodpeckers, and other 

 birds, could learn to eat these eggs, as European birds are said to do, they would 

 then have an increased food-supply the year round. Naturally, they would 

 increase in numbers, and thus an effective natural check to the gipsy-moth 

 in America would be established, provided these birds were protected. 



"The brown-tail moth is more exposed to the attacks of birds than is the 

 gipsy-moth, since the larvae hibernate in their nests in curled-up leaves that 

 remain on the tree all winter (see illustration). Already some birds are learn- 

 ing to open these winter nests and to extract the larvae from them. If the birds 

 once learn this lesson thoroughly, the power of this pest will be greatly 

 lessened." 



The Red-winged Blackbird and Blue Jay seem to have found out this new 

 food-supply, .while a number of other species eat the hairy caterpillars which 

 have crawled out of their winter nests, and also of the moths upon their emer- 

 gence from the pupal stage. 



The variety and number of insects are so great that, if birds had no other 

 kind of food-supply, there would doubtless be more than enough for all of 

 them, provided there were less cold weather and more warm weather. 



In the remarkable economy of Nature, however, every form of life has 

 its place, its season, and its work. To study the intricate relations which 

 result from this order is a life-long task. Perhaps this is one chief reason 

 why nature-study is so absorbing, because there is so much to learn that is 

 entirely new. Surely, in no other study can teachers and pupils be discoverers 

 and observers together to better advantage. 



But, to go back to the food of birds, numberless as the insects are, birds 

 find other kinds of food awaiting them when they journey northward. Let us 

 turn for a moment to the lists of trees, plants and animals which we studied 

 in connection with the distribution and migration of birds, taking the Robin 

 as our guide. (See Bird-Lore, Vol. XIV, No. i, p. 57; No. 5, pp. 303-306; 

 No. 6, pp. 364-368; Vol. XV., No. I, pp. 53-57-) 



How delightful a trip it would be to fly with the Robin, from one place to 

 another, from one tree to another, somewhat slowly at first, then more and 

 more rapidly as spring hurried by us, seeking the distant North? 



Through tropics and semi-tropics, great plains and deserts, pine-barren 

 country, by mountains and valleys, we should go; each day almost, finding 

 new feeding-areas and nesting-places. If we could count the different trees 

 which a Robin visits on its migration-trip, and the different things which it 

 finds to eat, what a long list it would make! 



