WHITE-FACED TREE DUCK 125 



the male took no part in the incubation, though he carefully guarded the nest. It 

 appears probable, therefore, that like many other birds having no sex-dimorphism 

 of plumage, the male often, though not always, assists the female. 



The period of incubation is not definitely known, but has been given in a general 

 way as from twenty-eight to thirty days (Bergtold, 1917). The pair that bred on 

 Lord Lilford's estate hatched their clutch in twenty-eight days. It would not be 

 out of keeping with the relationship of the genus if the incubation period turns out 

 to be rather longer than twenty-eight days. 



Status. This species is very abundant in almost all the central portions of its 

 range except in the heaviest forest belts. Some reference to the size of the flocks that 

 have been recorded, has already been made above. In many parts of its range it is the 

 commonest duck, though in Guiana not so common as Dendrocygna bicolor (F. P. and 

 A. P. Penard, 1908-10). It is especially abundant on the rivers of the Sudan, and, 

 so far as is known, is holding its own better than other ducks. In the heavy jungles 

 of the Upper Congo, however, I am told by Mr. J. P. Chapin that, like all other 

 water-fowl, it is extremely scarce. 



Enemies. No specific information is available. The young are no doubt preyed 

 upon by alligators and crocodiles. Wounded individuals were pounced upon by the 

 great White-headed River Eagle on the White Nile (A. Chapman, 1921). 



Damage. Hartlaub (1877) and Layard (1875-84) speaking of Madagascar, say 

 that these birds cause considerable damage to the rice-fields. Von Heuglin (1873) 

 makes similar remarks as to northeastern Africa. 



Food Value. The flesh of the White-faced Tree Duck is invariably excellent, 

 regardless of the character of the country in which it is killed. The whole group is 

 famed for the excellence of its flesh, and this species is no exception to the rule. 

 Observers who have particularly noted its culinary value, are all of the same opinion 

 (Hartlaub, 1877; R. Schomburgk, 1848; Milne-Edwards and Grandidier, 1876-81; 

 Wied, 1832; Witherby, 1901; and numerous others). 



Hunt. C. Grant (W. L. Sclater, 1912) speaks of the excellent shooting which he 

 obtained in Zululand by lying between two lagoons and sending natives around to 

 drive the birds up. The natives catch them easily on the Zambesi with traps con- 

 sisting of a flat stone propped up by a stick (B. Alexander, 1900). They are not 

 especially shy or hard to shoot, as was noted before under Wariness. 



Behavior in Captivity. These Tree Ducks are one of the species most commonly 



