1 84 SEA-BIRDS 



fulmars may skip a day or two, and at first may stay only for a few 

 hours on land. Male albatrosses may desert the colony for a few days 

 at laying-time. But gradually, as the colony becomes fuller with later 

 arrivals, those in possession of territory are less and less willing to 

 leave it, until at least one or other of the pair remains constantly on 

 duty. Courtship and defence of territory are now in full swing. 



As might be expected the awkwardness of these oceanic birds on 

 land (their feet are placed too far to the rear of the body to make an 

 upright stance possible, except in the albatrosses) prevents a very 

 elaborate display. But clashing and scissorsing of bills is part of the 

 ceremonial. The courtship of the nocturnal petrels has been difficult 

 to observe: but it is not difficult to hear the accompanying noises, 

 which must be very nearly the most weird in nature. The shearwaters 

 make indescribable crowing and screaming calls, and the storm- and 

 fork-tailed petrels have squeaking and purring notes. The fulmar 

 sings a curious cackling song, opening wide its dark purple mouth 

 towards its mate, and waving its head from side to side and up and 

 down, without moving its body much or opening its wings, as it sits 

 on a cliff-ledge. In the excitement oil may be passed between the 

 courting birds. Because fulmars nest in the open their display has 

 been more observed than that of other tubenoses. It probably is 

 typical for all these primitive, small-brained birds. Display is mutual, 

 and may take place between more than two birds (Manx and little 

 shearwaters, fulmar, storm-petrel), "visiting" by unemployed birds 

 being a habit of the courtship period of the tubenoses up to the time 

 of the laying of the single egg. 



Alone of the North Atlantic tubenoses the fulmar does not burrow, 

 although it will appropriate the entrance to the burrow of other birds 

 or rabbits. This may be associated with the fact that the fulmar is power- 

 ful enough to be able to drive away almost every avian territorial com- 

 petitor (Fisher, 1952). Normally it inhabits steep cliffs above the zone 

 of the kittiwakes and guillemots, where its increase is said to have 

 pushed out the herring-gulls. It has also been accused of driving 

 cormorants, shags, guillemots and razorbills from the ledges; but 

 there may have been a confusion of sequence and consequence, for the 

 fulmars may simply have taken advantage of space vacated when 

 these species were decreasing. On some islands the fulmar also nests 

 on the ground, on screes, on ruins and on occupied buildings; it 

 has become very plastic in its nest-site selection. 



The comparative tameness and fearlessness of the fulmar is believed 



