THE AUKS 279 



(or the chick) alone; one or other of the pair (or of other adults of the 

 colony?) remains with it. Thus it is protected from attack by gulls, 

 skuas, etc. ; but at the same time it is not safe from the risk of being 

 stolen or pirated by neighbouring adult guillemots. 



Puffins are essentially sociable birds. During the period when 

 one or other of the pair is incubating it is out of sight of the main 

 colony and is thus denied the stimulating visible presence of its fellows 

 which the guillemot enjoys. As if to make up for this, at certain periods 

 of the day, and especially on summer evenings, both male and female 

 puffins abandon the egg for two or three hours at a stretch, and sit 

 about and parade on the cliffs in a recreational assembly. The egg 

 does not appear to suffer as a result of this temporary cooling. For 

 the rest of the twenty-four hours it is probably much more steadily 

 incubated than those in the restless colonies of the razorbill and 

 guillemot. Observations on large colonies of these two species show 

 that there is a constant interference in incubation by the shufflings 

 and movements of the massed birds, the egg being frequently uncovered 

 in the process. 



The scene in the common guillemot colony is fascinating to watch. 

 Gatke, in his book on Heligoland, describes the guillemots aptly as 

 making an "endless obeisance" and the birds all talking volubly 

 about nothing in particular. The larger colonies seem to bubble 

 over with a non-stop excitement as a result of the perpetual bobbing 

 and bowing and shaking of each head and of the mild squabbles 

 of close neighbours and of the disturbances caused by each new arrival, 

 who is greeted so boisterously. When alighting in a colony the guillemot 

 announces its arrival with loud squawks, as if to warn those on the 

 ledges to make room for it, and it is usually received with apparently 

 aggressive cries. On the ledges progress is by means of a shufflng 

 walk with the whole tarsus pressed on the ground at each pause, 

 the body being held perpendicular. The razorbill walks in the same 

 way. Sometimes, when flying down to the sea, the auk moves its 

 wings at about half the usual speed, giving the appearance of slow 

 motion or, as it has been called, "butterfly" flight; in the puffin this 

 change in the usual mode of flight takes the form of a curious gliding 

 with the wings held high and the wing-tips rapidly fluttering in a 

 kind of "moth" flight. 



The eggs of the guillemot, varying so much in colour, are large and 

 pyriform; a design which minimises rolling but does not always 

 save the egg from tumbling over the narrow ledge. Johnson (1941) 



