

In Canada Geese there is a nervous shaking and uptilting of 

 the head when a bird is disturbed. 



man, she does not communicate a message of danger to her young. When 

 they hear her distress notes, they seek to escape perils of which they are 

 not aware; the response is to the mother's voice, not to the danger. Thus 

 one summer day a village-bred family of Blue-winged Teal walked into my 

 yard, the babies still wearing the egg-tooth, evidence that they were less 

 than forty-eight hours out of the shell. The mother was very tame, not at 

 all bothered by us as we followed close behind, nor were the babies dis- 

 turbed. We herded the family into the corner of the fence, and there I 

 gently lifted the hen from the ground. The moment I touched her she ut- 

 tered an alarm note, and the ducklings quickly hid in the grass. 



In Canada Geese, as in several other geese, there is a nervous uptilting 

 and shaking of the head when a bird is disturbed. As one individual begins 

 this action, its companions become alert, and the movement is repeated by 

 all members of the flock. When shaking reaches a certain degree of intensity, 

 the birds invariably take to the air. "Such formalized preparatory move- 

 ments often have communicative function, each individual of the species 

 being brought into the flying mood by its companions' movements" (Tin- 

 bergen, 1942:90). 



Again, if we consider the social releasers as a part of the bird's vocabu- 

 lary, we may draw an analogy from human behavior. We, too, have a vo- 

 cabulary of signals. A neighbor drops in to sit for a chat. Half an hour later he 

 places his hands on the sides of the chair. He has not yet said, "Well, I must 

 be running along." But the signal of his hands cannot be mistaken, and the 



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