THE GANNET 371 



to my knowledge been described in any ornithological work, 1 1 venture 

 to call particular attention to it. In its most complete form the action, 

 in the case of a sitting bird vacating the nest, is as follows : the bird, 

 instead of responding to the noisy salutations of its mate, rises silently, 

 with a solemn stiffness of demeanour, and stretches the neck and beak 

 right up and slightly backward. Scanning the heavens with fixed 

 preoccupied eyes, it turns slowly and cautiously round, as if treading 

 on thin ice, and then, leaving the nest to its mate, marches, still 

 gazing aloft, wings more or less erect, tail stiffly deflected, to 

 the edge of the ledge, whence it dives into the air, uttering an 

 almost indescribable note, a kind of long-drawn wailing " yee-orrrr" 

 This note, I found, varied greatly in pitch. It was never used except 

 to terminate the strange ritual here described, which was the regular 

 formal method of quitting the ledge, whether after changing places 

 on the nest or not. Like the sex display, it was subject to variation 

 in detail, and sometimes the bird dispensed altogether with the 

 posturing, being content to utter the note. Occasionally it omitted 

 both, especially when alarmed. 2 



I can offer no satisfactory explanation of this peculiarity in the 

 gannet's behaviour. It has four salient features the erection of the 

 wings, the depression of the tail, the stiffly erect neck, and the final 

 wailing note. The erection of the wings may arise through some 

 process of mental association with the act of flight itself; it can 

 hardly be a preparation for flight, for there is no necessity for raising 

 the wings when, as sometimes happens, the bird is several feet away 

 from the edge. The same applies to the deflected tail, which may be 

 kept deflected when the bird is on the wing, in order to break the 

 velocity of the descent through the air. But how the rigid upright 

 neck and a special note should come to be associated with so simple 

 an act as taking flight, is very difficult to understand. 



1 In British Birds [mag.], iv. 163 (1910), Mr. Bentley Beetham has described, as part of an 

 article on the " Position Assumed by Birds in Flight," the movements of the birds' wings 

 previous to " letting off," but not the ceremonious preliminaries. 



8 The description of the quitting posture here given is based both on written and photo- 

 graphic evidence. 



