Birds of Britain 



accompanies her when she comes off to feed. The incuba- 

 tion period of this species is rather shorter than with most 

 Ducks, and lasts between twenty-one and twenty- three days. 

 The young are solely looked after by the Duck, and when 

 first hatched their bills show no trace of the broadening 

 and flattening, characteristic of the adult. 



During the summer the Drake assumes an "eclipse" 

 plumage, which somewhat resembles that of the Duck. In 

 October he begins, unlike most other species, to assume 

 an " intermediate " plumage, in which the head is very 

 dark but not metallic, and the white of the breast is 

 obscured by dark transverse bars. The full plumage is 

 not usually complete till the end of February or early 

 in March. 



In this country our breeding birds are practically 

 resident, only shifting from their nesting -quarters when 

 frozen out. The majority of birds met with, however, in 

 winter are immigrants from the Continent, who leave us 

 again in March. 



The adult Drake in full plumage is a beautiful bird. 

 The head and upper neck are metallic green ; lower neck, 

 breast, and scapulars white ; back brown ; shoulders pale 

 blue; greater wing coverts white. The under parts are 

 deep chestnut ; speculum green ; bill black ; legs orange. 



The Duck is dark brown, with light rufous buff edgings 

 to the feathers. Shoulders bluish. The young at first 

 resemble the Duck, and in November begin to assume the 

 " intermediate " plumage described above, except that the 

 breast feathers are spotted and not barred. It does not 

 always assume its full plumage in the first year. 



246 



