MARBLED DUCK 7 



Association with other Species. No observers, so far as I know, have noted 

 any sociable tendencies in this duck. No doubt in the wintering areas of North 

 Africa and northwestern India they are to be found in the same resorts as those of 

 other water-fowl, and Hume and Marshall (1879) speak of Shovellers or White-eyed 

 Pochard getting up from the same lagoon. 



Voice. Few writers have distinguished the notes of the two sexes. The low croak- 

 ing whistle mentioned by Lord Lilford is unquestionably the call of the male, while 

 the distinct, rather hoarse quack heard by Hume (Hume and Marshall, 1879) is 

 almost certainly the note of the female. In respect to voice the species seems to be 

 very similar to the Teals. 



The trachea, according to Favier (in Dresser, 1871-81) is somewhat narrower at 

 the extremities than in the middle part, and the bulla ossea is left-sided, bony, and 

 about the size of a cherry. 



Food. No careful analysis of stomach contents has been made, but from the 

 statements of most writers it seems that the food is the same as that of other shoal- 

 water ducks. Still, I think this species must be dependent on minute animal food, for 

 it does poorly in captivity. Favier noticed that in Tangiers they fed chiefly on 

 winged insects {Myrmelion) and Loche (1867) found them in Algeria feeding on 

 crustaceans, insects, and worms. In India Hume and Marshall (1879) state that the 

 diet includes leaves, shoots, rootlets, corms, and seeds of aquatic plants, intermingled 

 with worms, fresh-water shells, insects of all kinds and their larvae. 



Courtship and Nesting. The display of the Marbled Duck has never been ade- 

 quately described. Zarudny (1889-90) noted that when about to fly, the birds 

 lower the neck and raise the head, and that this movement is rare, excepting 

 during courtship. This seems to indicate that the courtship is a very simple affair, 

 but Finn (1915) says that when displaying, the male "jerks back his head on to his 

 shoulders." 



Considering the fact that many of these birds are sedentary in a warm climate 

 and that none travels more than a short distance to the breeding grounds, the, nest- 

 ing season is extraordinarily late. In the Canaries young have been taken in May 

 (1858) but in Spain, Morocco, and Algeria nests are rarely found before the middle 

 of Mayor beginning of June (Favier,./wfe Irby, 1875; H. Noble, 1902; Zedlitz, 1914b). 

 In Cyprus nests have been taken on May 24 (Baxendale, 1915), and a clutch of 

 seven highly incubated eggs as late as July 5 (Bucknill, 1911). In Transcaspia, where 

 the species breeds in great numbers, the laying season is very irregular. In early 

 July some young were already on the wing, while others were only just hatched 

 (Zarudny, 1889-90). The dates for Mesopotamia are for May and June. In 



