144 THE GULLS 



open and vociferous, followed by downward swoops. Distinct again 

 are the assaults of flying birds upon sitting. The best time for watching 

 these is during the periodical simultaneous flights that a number of 

 birds in a colony or part of a colony will make when recently disturbed. 

 The upflight from the ground is comparatively silent. Even when 

 not looking at the part of the gullery in which the upflight occurs, 

 one knows it is taking place by the sudden hush. No sooner do the 

 birds halt in mid-air than the noise again begins, and it goes on 

 increasing on the down-flight till it reaches a climax at the moment 

 that precedes alighting. Then there is a wild confusion of white 

 fluttering wings, of red legs flashing in the sun, and from the red wide 

 open beaks there issues a fast and furious storm of screams. It is at 

 this moment that sitting birds have to be on their guard ; they often 

 sit, with neck and head upstretched and beak wide open, to defend 

 themselves from a playful dig in the back from their over-excited 

 mates or comrades in the air. 



In the universal incessant chorus of disapproval that descends 

 upon the intruder into a colony of blackheads, it is no easy task to 

 distinguish the different notes that are uttered, especially when 

 allowance is made for distance and differences in pitch. One note, 

 however, it is possible to study in its most intimate details, and that 

 is the harsh screech that ends the swoop of the angry gulls near 

 whose nest one happens to be. It is uttered at the moment when 

 the bird, instead of dashing itself upon the object of its wrath, as it 

 seems about to do, suddenly checks its flight and swerves away to 

 mount and repeat the attack. It is repeated again and again till the 

 victim is heartily glad to beat a retreat. It provides the strong notes 

 in the gull orchestra, and may be variously syllabled as a strident 

 qwerrr, qworrr, or qwarrrr. During the descent to the attack the bird 

 utters a rapid tt, U, trrr, tt, tt, trrr. This note forms a background 

 of sound in the general chorus. A third note is a curious ttuk, or 

 ttup ! which may be uttered as a single sound, or repeated, sometimes 

 slowly, sometimes rapidly. When rapid, it seems to merge into the 



