( 18 ) 

 ON THE IDENTIFICATION OF DUCKS' EGGS. 



BY 



HEATLEY NOBLE, m.b.o.u. 

 (Plate I.) 



The eggs of various species of Anatidoe are so frequently 

 sent to me for identification that I have gained some 

 experience in the matter, and it has been thought that 

 the results of that experience might be of some interest 

 to readers of British Birds. 



There are three means of identification — (1) the eggs 

 themselves ; (2) the down found in the nests ; (3) the 

 feathers which are generally mixed with the down. The 

 last provides by far the most important and certain means 

 of identification, although it is seldom mentioned by 

 'v\Titers on this subject. The down by itself is not 

 reliable except in isolated cases. 



Take, for example, that found in the nests of the 

 Wigeon and the Shoveler ; it would be a bold ornithologist 

 who would guarantee to separate the two were they mixed 

 together. The clue is given by the feathers, those of the 

 Wigeon being white sometimes with grey centres, and quite 

 unmistakable. Then, again, the down in different nests 

 of the same species is often so dissimilar that it appears 

 to belong to different species. I think I shall be able to 

 shoAv that if the eggs, down, and feathers are all con- 

 sidered in relation to each other, identification, if not 

 absolutely certain, becomes little doubtful. 



Occasionally cases arise which are distinctly difficult. 

 Last season, for instance, a beautiful nest of snow-white 

 down, with white eggs and white feathers tipped with 

 grey, was sent me from Ireland. The nest had been taken 

 in heather, not from a hole, as might be expected from 

 the colour of the down. It certainly belonged to no 

 British, or even European, breeding duck, neither was it 

 that of any foreign duck usually kept in confinement. 



