70 EDWARD A. WILSON. 
without exception, it was given with the wing, and the claws were never used in 
the attack. While her partner was thus doing his best to frighten off the intruder, 
the sitting bird was loudly and persistently advertising the exact position of the 
nest, nor would she leave her post till we had come, sometimes, to within a yard 
or two. 
The bird’s cry is much like that of other gulls, a loud and anxious rapidly 
repeated cry, and very harsh. But the cry of the fledgling is very different. At Cape 
Adare I thought for some time that there must be a bird of the sandpiper type about, 
for I constantly heard a liquid, melancholy whistling trill. By degrees, however, 
it brought me to a fledgling Skua, which was just beginning to use its wings for 
flight. I saw it whistling with a most musical note, wholly unlike the harsh cry of the 
adult. 
The bird makes no attempt at concealment, though its colour as well as the colour 
of its eggs might be considered to be specially adapted to the nature of the ground, 
but with such habits as the Skua’s there is obviously nothing in it. Even when the 
bird is away from its nest, one has but to climb a little rocky hillock, and somewhere 
in the hollows under one’s eye will be apparent two eggs in a shallow scooped-out nest, 
easily visible even at a distance of ten or twenty yards. There is never any attempt 
at nest-making other than the shallow depression in the gravel on which the eggs are 
laid. Once only I found a little collection of the Adélie penguin’s tail feathers laid in the 
hollow, as one occasionally finds a little twig or a few bents laid in the hollow of a 
Peewit’s nest,* but as a rule in a Skua’s nest there is nothing at all, We never found 
more than two eggs in a nest, and in a certain number of cases in every rookery one 
ege is considered sufticient for incubation, the other doubtless having been stolen by a 
marauding neighbour. In many cases there is to be found in company with a normal 
egg another with a much thinner shell and a pale bluish ground, but with little or no 
marking. Sometimes a thin-shelled egg may be ringed round the upper third by 
minute and crowded dots and speckles, but be lacking in the characteristic blotches of 
the normal egg. These I took to be the results of an effort to replace a stolen egg, the 
amount of shell and colour that the bird is able to secrete being nearly exhausted in 
the production of the first two eggs. In one nest I found a normal egg in company 
with another the size of a Blackbird’s.— All round the colony, in addition to the 
empty shells of sucked penguins’ eggs, are to be found the shells of Skuas’ eggs bearing 
similar evidence of theft and suction. 
A very favourite nesting site in McMurdo Sound was a group of moraine-covered 
islands on the western side, now known by the name of Dailey Islands. At Dellbridge 
Islands, also, on the eastern side of McMurdo Sound, we procured large numbers of 
Skuas’ eggs, but neither here nor at the Dailey Islands did the rule hold that Skuas 
always breed near penguins, for in each case they were quite alone. 
* Peewit = Vanellus vulgaris. 
t Blackbird = Turdus merula. 
