THE KITTIWAKE 191 



On both these cliffs the guillemots occupy the lowest and the 

 highest places. In the case of Cliff A, this was simply due to the 

 presence of large ledges near its base. 1 



A discovery forced upon my notice at these same cliffs, was that 

 the kittiwakes nested only on their southerly or south-easterly faces : 

 I was nowhere able to watch them without fronting a biting north- 

 easterly wind. The guillemots and razorbills were quite indifferent 

 as to aspect, a fact which made watching them in the early part of 

 the year a matter of comparative comfort, as one could sit so as to be 

 sheltered from wind and rain. On the Bass Hock, however, they nest 

 on ledges facing all aspects, but chiefly south-east and north-west. 



Laying begins toward the end of May, both sexes sharing in 

 incubation, which lasts from three to four weeks. As is the case with 

 many other species, there are usually a certain number of non- 

 breeding adult pairs and single birds, which cannot apparently find 

 room to nest, but exact information on this matter is still wanting. 

 That these birds, or some of them, are willing to assume the duties 

 of parenthood was shown by Faber, who removed a pair from a nest 

 containing eggs, which were thereupon incubated by another pair, 

 and the young hatched and reared. He found the same to be the 

 case with puffins, guillemots, little-auks, and others (Fratercula, Uria, 

 Mergulus)? 



The young are fed by both parents on regurgitated food. The 

 young bird shows its desire for food in a somewhat curious fashion ; 

 it stands in its usual position, but with the head and neck contracted 

 or drawn back between the shoulders. The head and beak are tilted 

 slightly up, and bobbed up and down with a regular automatic 

 action, that gives the bird somewhat the appearance of being a child's 

 toy worked by internal mechanism. Usually the young kittiwake 

 interrupts the movement from time to time to make a dab with 



1 Some years ago Mr. Jourdain noted that on the Bempton and Speeton Cliffs the kitti- 

 wakes nested on the lowest ledges, none high up. 



2 Naumann, Vogel Mitteleuropas, xi. 293. For examples of the same habit among Passerine 

 species, see above vol. i. 54, 55. 



