230 THE SHELDUCK AND SURFACE-FEEDING DUCKS 



a peculiarly wary and timorous bird, and wherever a large flock 

 may be feeding, one or other is constantly on the lookout against 

 surprise. Hence, like other and less suspicious members of this 

 tribe, they feed at night rather than by day. When they have 

 acquired a certain amount of confidence, however, they do feed by 

 day, and at such times search with zeal for aquatic insects of all 

 kinds, most of which are taken from the water, but some are 

 caught when on the wing with great dexterity. Small Crustacea 

 and small molluscs are also greedily devoured, but for the most 

 part they seem to feed on water-plants. Such as grow in shallow 

 water are uprooted and eaten as they float at the surface, and to 

 secure these the body is half-submerged, so that the hinder half of 

 the body projects vertically from the water. But they rarely or never 

 dive. When swimming they float high in the water, and commonly 

 with the tail much raised, though never so much so as in the long- 

 tailed duck. By day they are remarkably silent birds, the male, at 

 no time vociferous, when flying will occasionally utter a low whistle, 

 and when frightened or wounded a sharp "cheeping" note like 

 that of a wigeon. The female, especially at night, gives tongue to 

 a low quack. During courtship both sexes become rather more 

 loquacious, and then only does the male emit a curious double note 

 identical with that of the teal under the stress of like emotions. 



Of this courtship but little seems to be known, and most of what 

 has been recorded has been observed by Mr. J. G. Millais, from 

 whom we gather that the male in display presents actions recalling 

 in some respects those of the mallard, and in others of the wigeon. 

 Thus a number of males will often be making advances to the same 

 female, and suddenly all will start up and raise the tail. At other 

 times all will stand up in the water, and bringing the bill down on 

 to the breast will then swiftly jerk it upwards, mallard fashion, 

 at the same time uttering a low soft note. According to Naumann, 

 the male often swims round his prospective mate uttering a deep 

 cliik, which, if the observer be fortunate enough to be sufficiently near, 



