130 



USEFUL BIRDS. 



the time that could be spared for this kind of work. In 

 1899, however, Mr. Mosher was detailed for this work early 

 in the season, and instructed to spend such time daily as 

 was necessary to observe the feeding of birds on these in- 

 sects. He was requested also to make full notes each day. 

 As many of these field notes as the available space will per- 

 mit are given below. Many of the observations were made 

 in the morning, but not during the earlier morning hours, 

 when birds feed most actively. The weather being mild, on 

 the 24th of April a few brown-tail moth larvae that had win- 

 tered on the trees began to crawl out. 



APRIL 24. In Cambridge, near Fresh Pond, I 

 saw a large flock of Red-winged Blackbirds foraging 

 on a newly plowed field, and from a large pile of 

 dressing they were taking flies. From a pear tree 

 near by three of them took brown-tail moth larva? 

 from the opening buds. They were in the tree seven- 

 teen minutes, and were eating all the time. 



APRIL 26. In Revere, near the Maiden line, I 

 found a pear tree with a brown-tail moth web on it. 

 A pair of Crow Blackbirds came, and remained about 

 forty-five minutes in that tree and the one adjoining. 

 They plumed their feathers for a while, then began 

 looking over the tree for food. They alighted sev- 

 eral times on the branch that was most infested, and 

 picked the larvae from the buds and from the crevices 

 of the bark. 



A little later the tent caterpillars began 

 hatching, under the influence of the warm 



Fig. 41. Web of 



the brown-tail spring sun, and the birds could find a few of 



moth caterpil- , 



lar, reduced. them. 



APRIL 27. In Stoneham, off Forest Street, I observed the birds 

 feeding on tent caterpillars. A Black and White Warbler came three 

 different times, and took the small caterpillars from the buds. The 

 Chickadees visited the bush, and took a few caterpillars. None seemed 

 to take them from the web. The May flies were unusually plentiful, 

 and the Least Flycatchers were feeding on them. 



APRIL 28 On Mr. Button's estate, Maiden, I saw Black and 



White Warblers feeding freely on tent caterpillars, and also Chickadees 



