TRAVELS OF WATERFOWL 



be explained on the basis of curiosity. I suspect, however, that a band of 

 ducks seeking congenial company might turn at almost any noise strange or 

 poorly heard, making the full response when the source was identified. The 

 hunter's rule when calling ducks or geese is to keep quiet after the birds 

 have turned, lest the ruse be detected. 



Before leaving the subject of voice, note must be made of the duck's abil- 

 ity to localize sound. Waterfowl readily locate a noise even though they may 

 be moving rapidly through the air and the source of the sound is hidden 

 from their sight. Once a band of passing Redhead drakes wheeled to fly 

 directly over my hiding place when I imitated a Redhead female. In autumn 

 twilight Peter Ward and I have called Mallards directly to our voices, al- 

 though we were hidden and without decoys. 



Movement is another means of communication. All or most functional 

 actions serve as signals. For instance, in ducks the quickly lifted head is a 

 signal of alarm. A hunter attempts to sneak up on a flock of loafing Mallards, 

 but one bird sees him, lifts its head, and in a flash every head in the flock 

 is raised, all alert, although only one bird saw the hunter's movement. The 

 lifted head of the first bird was simply an adjustment ; he raised his eye-level 

 to see better. His movement released similar actions in his companions 

 which, either innately or through conditioning, associate the sudden lifting 

 of the head with the presence of danger. When the hunter makes another 

 false move, the entire flock is away in a flash, although only several may 

 have seen his second blunder. The action of an individual is repeated by the 

 flock. Obviously this rapid reaction is of great survival value ; escape move- 

 ments would be far less efficient if each duck examined the cause of an 

 alarm before departing. 



The native guide's explanation of the first Mallard's behavior would be 

 that this bird told the others of the hunter's presence. W r e know that his ac- 

 tion, as a signal, is merely a response to a situation. The drake does not in- 

 tentionally communicate with his fellows, and his behavior is the same when 

 he is alone. Let us note that the lifted head is not a stereotyped response 

 to danger, but depends entirely on the Mallard's condition. During the 

 summer wing-molt, when the male is flightless, he quickly lowers his head 

 when aware of danger, and the lowered head is the signal for other flightless 

 males to lower theirs. The flightless drake does not wish to see better but 

 to avoid being seen, and with lowered head he is much less conspicuous. 

 The same behavior is to be noted in a wounded duck. 



When the mother Blue-winged Teal feigns injury in the presence of a 



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