THE REACTIONS OF BIRDS TO SOUND STIMULI 217 



turned toward it at once and begged for food. If food were 

 not forthcoming, this reaction became less and less vigorous 

 on successive trials, and finally ceased altogether until the bird 

 had been fed again. In the afternoon of the same day the 

 thrush was taken outside the cage; and even under these condi- 

 tions, and when at some distance from it, the bird continued 

 to orient itself toward the source of the sound and to beg for 

 food when the cage door was rattled. During all of these 

 experiments the bird kept its eyes tightly closed. 



Further experiments were planned, but the thrush died on 

 July 30. 



3. Observations on birds of the cedar bog. On August 13 

 I went down into a dense cedar bog about two miles from the 

 station, and, while in the more open parts, I ran across a flock 

 of chickadees, golden-crowned kinglets, and brown creepers, 

 numbering perhaps thirty individuals. I tried the effect of 

 whistle blasts, of clucking with the mouth, and of shouting, 

 all at a distance of less than fifteen feet, without obtaining a 

 positive reaction from any of these birds; nor did this surprise 

 me, when the fearless habits of these birds were considered. 

 When I clapped my hands, however, a kinglet did fly to a farther 

 tree; but this was undoubtedly due rather to the effect of the 

 visual than to the auditory stimulus. Later I tried the effect 

 of a whistle blast on a black-throated green warbler, with more 

 positive results. The bird raised its wings as if to fly, but soon 

 settled back and then continued its search for food. Subsequent 

 trials produced no result. 



4. Observations on young cedar waxwings. As was stated 

 in the introduction, these waxwings were so accustomed to 

 sounds of all sorts before my experiments were begun that 

 almost no positive results were obtained. In fact the only 

 thing definitely established was that these birds were more 

 responsive to sound stimuli before being fed than afterward. 



5. Observations on certain shorebirds. On August 21, I made 

 a series of observations on some solitary sandpipers, least 

 sandpipers, and kildeers which were feeding on the beach near 

 camp. I tried whistle blasts, shouts, and percussive sounds, 

 both vocal and clapping my hands. The only reaction I observed 

 among the sandpipers was given by a solitary sandpiper, which 



