276 SEA-BIRDS 



fishing under water), since it momentarily hides the conspicuous 

 bill from a partner. The well-known bill-rubbing ceremony of the 

 puffin is like the bill clashing of the gannet; it may have its origin 

 in threat display. It is initiated as a rule by the male: approaching his 

 partner in the threat attitude, he begins to quiver his head to and fro, 

 thus signalising that his intention is not hostile (the bill remains stiff in 

 hostile display). Elements of threat seem to remain in the violent 

 pushing movements of the male as he shakes and presses his bill against 

 one side of the female's, and she is sometimes pushed off her balance 

 as a result. In a large assembly on land a bill-rubbing pair, or a 

 pair fighting, at once attract neighbours, who crowd round, and, 

 by joining in the ceremony, break it down; we have seen three puffins 

 bill-rubbing together, with more trying to join in, or three or four 

 in a fight — but always the action was broken off quickly, and the 

 birds separated and moved their normal distance apart (Lockley,i953). 

 Puffins are intensely curious of all movements near them in the 

 puffinry, and will toy with the snare or hook at the end of the 

 fowler's rod as it slides over the ground towards them. 



Bill-rubbing or pushing takes a milder form in the little auk 

 (Foster et al., 1951) and the razorbill (Paludan, 1947). Courting 

 guillemots are so short of manoeuvring space on the crowded ledges 

 that the pair may stand shoulder to shoulder in courtship, caressing 

 each other in this position, bowing and groaning with heads sideways 

 (Johnson, 1941). The holding of a fish in the bill of a guillemot early 

 in the season Johnson considers to be part of the courtship ceremonial, 

 and he records its retention for long periods — up to four hours. We 

 may compare this with the fish flights of the terns (p. 255). 



Armstrong (1940) considers that the brilliant red colour of the 

 legs of the black guillemot may be functionally useful in the under- 

 water chases which are "nuptial, connubial and recreational." As 

 the tysties flutter along like large exotic water-butterflies just below 

 the surface, they may be guided by the bright webs of the leaders. 

 Certainly in this rotund species the feet are used as paddles more 

 freely under the water than in other auks. But puffins, with vermilion- 

 coloured legs and webs, are less given to this form of social behaviour 

 than are the black-footed razorbills. 



Black guillemots face each other, bowing and whistling until 

 the female suddenly squats flat on the rock with her tail erect; the 

 male mounts, paddling with the feet to maintain position while copulat- 

 ing. Razorbills and common guillemots mate, noisily groaning, at the 



