136 BIRD BEHAVIOUR 



Among Parrots, young Cockatiels and Keas have 

 down, but Budgerigars and Ring-necked Parrakeets 

 are bare. So, apparently, are all Kingfishers, 

 Rollers, Woodpeckers, and Bee-eaters, but Hoopoes 

 boast of <c a little bit of fluff," though Hornbills 

 are naked. Nightjars are downy, and so are Owls 

 and Hawks, the down of Owls being in most cases 

 in two crops, the first one white, like that of most 

 young Hawks, while the second one is coloured 

 and often barred. Curiously enough the young of 

 the Snowy Owl is black, like that of the White 

 Tern (Gygis), and the goslings of the Snow-Goose 

 are very sooty- looking little things at least hybrids 

 between the white and blue-grey forms are. 



Among the Geese, uniform though their life- 

 habits are, all being big strong wary birds, living in 

 the open, able to swim, and feeding on vegetable 

 food, there is a remarkable variety of down-colour 

 and pattern in the young. Some are nearly self- 

 coloured, olive ranging into yellow, as in the case of 

 the common Grey Goose (goslings are only all yellow 

 when the offspring of a white tame Goose, just as 

 all yellow ducklings are the offspring of tame Ducks), 

 or into black, as in the Snow-Goose ; and some 

 have a strong contrasted pattern, dark over most of 

 the upper part and white below, as in the Bernicle, 

 while in the highly specialized Cereofsis the goslings 

 are striped light and dark. 



Generally speaking, however, patterned down 

 striped, pied, marbled, or spotted is characteristic 

 of active chicks, while the passive nestlings, when 



