158 BRITISH SEA | BIRDS. 
composed of fish. During the non-breeding 
season Divers are not particularly noisy birds, but 
at their nesting-places the cries they utter are both 
loud and startling, described by some listeners as 
similar to the screams of tortured children; as 
shrieks of maddened laughter, or as weird and 
melancholy howls by others. 
It is a somewhat remarkable fact that the Great 
Northern Diver breeds nowhere in Europe, except 
on Iceland. It is an American species, and nests 
from Greenland westwards to Alaska, south of the 
Arctic circle to the more northern of the United 
States. It reaches its breeding-grounds in pairs 
towards the end of May, as soon as the northern 
waters are free from ice. Its favourite nesting 
places are secluded tarns and lakes, and an island 
is always selected if possible, doubtless from 
motives of security. The nest—always made upon 
the ground—varies a good deal in size, according 
to the local requirements. On wet marshy ground 
it is large, and composed of a heap of half rotten 
sedges, rushes, reeds, and such like vegetation, 
lined with dry bits of broken reed and withered 
grass. On drier and barer situations it is little 
more than a hollow in the sand or hard ground, 
with, perhaps, a few bits of dry grass for lining. 
The birds are very alert and watchful whilst nesting, 
as if fully conscious of their comparative difficulty 
in escaping from danger on the land. One bird is 
generally on the look out whilst the other sits, and 
