196 THE BIRD WATCHER 
eaten at all, I cannot say ; but I have noticed that the 
guillemot, also, somet#Mfes brings in a sand-eel to the 
ledges, that has been neatly decapitated. I can quite 
understand that the head of a herring, if swallowed by 
a greedy young chick, might have a bad effect on it, 
but that the old birds, through some process of 
natural selection—-for we cannot suppose that they 
are impelled by ordinary foresight—should have 
acquired the habit of first decapitating the herrings 
and thus removing the risk, seems very unlikely. On 
the other hand, that they should eat one particular 
part, and no other, of each fish that they bring to 
their young, is almost as difficult to believe. I have 
elsewhere suggested another explanation,’ but this 
too I find it difficult to adopt, and the only remaining 
one I can think of is that the gulls who catch these 
herrings, and who are robbed of them by the skua, 
either bite off their heads in order to kill them, or eat 
the head separately. Whatever the reason of it may 
be, I once more draw attention to the fact. 
At the tail, so to speak, of this track of herrings, 
I find another young great skua, and sit down by him 
to make my entry. He is a big chick, but the fluff 
still remains upon his head, neck, and under surface, 
springing from the ends of the true feathers, which 
have thus gradually pushed it out. On the back it is 
almost gone, thin patches of it only appearing above 
a thick brown panoply of the mature plumage. This 
chick is of milder mood than either of the other two. 
1 Bird Watching, p. 117. 
