The Mute Swan 



a black knob at its base. This knob is much larger than 

 in the male. The young are greyish drab. The so-called 

 " Polish Swan " is a variety of this species, in which the 

 young are white. Length about 56 in.; wing 27 in. 



THE COMMON SHELD-DUCK 



Tadorna cornata (S. G. Gmelin) 



Although somewhat local in its breeding haunts, this 

 species is fairly abundant round all our coasts in winter. It 

 is a Sea-Duck, being seldom found far inland, and its food 

 consists of small mollusca and marine insects, which it 

 seeks on our flat estuaries and along the shore. 



A rabbit-burrow in sand-dunes near the sea is chosen for 

 a nesting-site, and lined with a little grass, to which is 

 subsequently added an abundance of grey down from the 

 body of the female. Occasionally it makes its own burrow, 

 or other sites such as crevices between boulders or under 

 furze bushes are selected. The eggs, generally ten in 

 number, are creamy white. As soon as they are hatched 

 the mother leads her brood to the shore, where they feed, 

 making for the sea on the first sign of danger. 



During the pairing season this bird is very noisy, the 

 male uttering a short whistle, while both sexes run round 

 each other with out - stretched neck, making a curious 

 guttural chuckle. 



In winter large flocks of these birds visit us from the 

 Continent. These flocks may be seen resting out at sea by 



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