6o THE BIRDS OF THE BRITISH ISLES. 



position than most ducks. Even where there are a number of 

 lakes in one district the bird usually shows partiality for certain 

 waters, probably because they provide some particular food. In 

 Lakeland, Macpherson found it the commonest diving duck, and 

 this is still the case. As an expert diver it is distinctly ahead 

 of its relatives ; my notes give an average of twenty-three 

 seconds below the water, and of three or four seconds on the 

 surface between each dive. Thus when the bird is busily 

 feeding it is much longer invisible than visible. Often if 

 surprised it dives, swims out for a distance and takes wing 

 when it comes to the surface, and does not sink its body and 

 draw off from the shore like Tufted or Pochard. It is mainly 

 an animal feeder, diving for molluscs and crustaceans, and, in 

 fresh water, aquatic insects ; Prof Newstead counted over 150 

 water beetles of one species in the stomach of a bird. In its 

 nesting habits it differs from other ducks, for choice selecting 

 a hole in a tree ; it can be induced to make use of nesting-boxes. 

 The bill of the drake is blue-black, that of the duck darker 

 and tipped with dull yellow ; the legs are yellow, often orange 

 in old drakes, the irides golden. One summer I was able to 

 watch the progress of the moult into eclipse dress, for a 

 " pricked " drake in, I should say, its second spring, was 

 unable to migrate. In April its head was green, though with 

 less sheen than in an older bird, and the patch near the bill 

 was small though distinct. The head was quite brown by the 

 second week in July, and the cheek spot had entirely vanished, 

 though some authorities insist that it is retained ; white showed 

 on the neck, though flecked with grey, but the wing patch was 

 unaltered. At the end of August the bird reached its greatest 

 obscurity, and early in September the head darkened, and the 

 white patches showed more clearly on one side ; probably the 

 reason was that the damaged wing did not recover so quickly. 

 The bird was shot before it had attained full dress, and when 

 last seen in September the face spot had not developed. 



