362 CORMORANTS 



the rock. Again, a bird whilst standing, but not quite erect, will dart his 

 head forward and upward, and make with his bill as though snapping 

 at insects in the air. Then, after a second or two, he will throw his 

 head back till it touches or almost touches the centre of his back, and 

 whilst at the same time opening and shutting his beak, communicate a 

 quick vibratory movement to the throat. It looks as though he were 

 executing a trill or doing the tremolo so loved of Italian singers, of 

 which, however, there is no vocal evidence." 



The female will sometimes cosset with her bill the throat or neck- 

 feathers of her recumbent adorer, a favour which he acknowledges by 

 " sundry little pleased movings of his head." 



Green-cormorants begin in December to don their breeding- 

 plumage, when the crest on the head first makes its appearance 

 (J. Tomison, Annals Scot. Nat. Hist., 1904, pp. 18, 19). If the weather 

 is mild they begin nest-building as early as February, and complete 

 their nests in six to eight days. Often the nests are built so near 

 the water that the first heavy sea washes them away. One bird only 

 builds, while the other acts as carrier. 



The female begins laying in April, sometimes even earlier. Mr. 

 Tomison saw fifty-four nests on a space of rock not more than thirty 

 yards square, some of them within a foot of one another. 



The clutch consists of 2 to 5 eggs, 3 being the most common 

 number. " When the young are small, one of the parents acts as food 

 provider, but when they are a fortnight old it takes the united efforts 

 of both parents to convey sufficient food to their hungry offspring. 

 . . . The old bird comes in from the sea and alights at the side of the 

 nest. Immediately there is a rush made by the young to see who will 

 get to work first. The fortunate one shoves its head entirely out of 

 sight down the old one's throat, and by its movements seems to be 

 enjoying itself. I don't suppose they know what it means to get 

 enough ; but apparently the parent decides that question, for I have 

 often seen it shake off the one at work and give No. 2 a chance, and 

 then No. 3. ... I have seen five eggs and five young birds hatched, but I 



