Cfje Hutmfoon Societies! 



SCHOOL DEPARTMENT 



Edited by A. A. ALLEN, Ph.D. 

 Address all communications relative to the work of this 

 department to the Editor, Cornell University, Ithaca, N. Y. 



THE HOME-LIFE OF BIRDS 



THE YOUNG BIRDS, THEIR GROWTH AND CARE 



Young birds at hatching are of two general types. They are either precocial 

 or altricial. Precocial young resemble young chickens in that they are wide 

 awake when hatched, are covered with down, and are able, very soon after 

 drying off, to follow their parents in search for food, a large part of which 

 they find by themselves. Altricial young, on the other hand, are almost naked 

 when hatched, their eyes are not yet open, and they are cared for in the nest 

 by their parents for periods varying from a week or ten days with terrestrial 

 Sparrows, to nearly a year with the Condor and the Wandering Albatross. 



In general, terrestrial, diving and swimming birds have precocial young, 

 while arboreal birds and birds that search their food on the wing, have altricial 

 young. Among the former are the Loons and Grebes, the Ducks, Geese and 

 Swans, the shore-birds, the marsh-birds, and the fowl-like birds. Some young, 

 such as those of the Gulls and Terns, remain in the nest or, at least, have food 

 brought to them for weeks, but in other respects are entirely precocial, being 

 wide awake, covered with down, and able to run about shortly after hatching. 

 Other young, such as those of Hawks, Owls, Nighthawks, and Whip-poor-wills, 

 and even Herons, are covered with thick down when hatched but in other 

 respects are quite altricial, being blind at first and quite unable to help them- 

 selves for a long time. At the opposite extreme among altricial young are those 

 of the Flicker, the Kingfisher and the Hummingbirds, which are entirely naked. 

 The majority of Woodpeckers have a few hair-like feathers when hatched, and 

 Cuckoos have them quite thread-like. Young Cuckoos and Kingfishers are 

 worthy of attention again when they come to attain their first real feathers for, 

 unlike most birds, they remain in the sheaths until nearly full grown. For a 

 time the young birds seem covered with tiny lead pencils, and the transform- 

 ation to the fluffy feathers, by the breaking open of the sheaths, is very rapid, 

 requiring but a few hours. With other young birds, the transformation from 

 almost naked babes into fluffy feathered creatures is gradual. Whatever down 

 there is, is pushed out on the tips of the incoming juvenal feathers which 

 begin to break their sheaths before they are quarter .grown. In the case of a 

 Red-winged Blackbird, for example, the 'pin-feathers' have pushed the down 

 entirely out and are well grown by the end of the fifth day, and on the sixth, 



(294) 



