{Authors are responsible for nomenclature used.) 



The Scottish Naturalist 



No. 12.] 1912 [Decembe 



THE TUFTED-DUCK (FULIGULA CRISTATA 

 IN THE NESTING SEASON. 



By s. E. Brock. 



' V **AS* 



The notes, of which the following is a summary, have been made 

 chiefly at certain small pieces of water situated in the eastern district 

 of Linlithgowshire, the convenient accessibility of the locality having 

 allowed of systematic observations on the birds frequenting it. Here 

 the Tufted-duck might almost be described as summer-visitors, 

 arriving in pairs from mid- .March onward, and taking ■ their 

 departure almost immediately after the young broods have attained 

 independence. Winter occurrences are quite irregular, and each of 

 brief duration. On other waters of larger dimensions in the county 

 these ducks are regular winterers, in small parties ; and the total 

 numbers resident at that season are approximately equal to the 

 breeding-stocks of the district generally. They are most numerous 

 during the autumn months, when flocks of unusual dimensions are 

 sometimes to be met with. 



Adult drakes commence to assume the full plumage early in 

 September, and by the beginning of the following month the earlier 

 birds have nearly completed the moult ; but many individuals, some 

 of them perhaps birds of the preceding season, remain in imperfect 

 feather much later, often well into the new year. There is some 

 reason to believe that drakes are numerically superior to the other 

 sex. In a summary of a considerable number of notes on com- 

 parative numbers of the sexes, made during the last few years, 

 the males outnumber the females on a considerable majority of 

 occasions, the balance in their favour on all records amounting to 

 some 9 per cent. 



Although odd pairs may be found consorting together as early as 

 late January, it is not before the latter part of the following month 

 that sexual influences begin to show appreciable outward effect on 

 12 2 L 



