THE BIRD-LIFE OF LONDON 
with its body pressed close up to the trunk. If disturbed 
the light seems to cause it uneasiness, and it glides 
off on silent wings in an erratic, uncertain way, its only 
aim, apparently, to find another dusky nook. It is 
thoroughly nocturnal, heard but seldom seen, and seeks 
its prey in darkness. ‘This food consists chiefly of mice, 
rats, voles, shrews, young rabbits, and frogs, all the 
indigestible parts of which are thrown up in pellets. 
Small birds are occasionally caught. During winter 
the Tawny Owl is somewhat solitary, but at other times 
lives in closer company with its mate, to which it 1s 
apparently paired for life. ‘The same retreat and nesting- 
place is often used year after year. It makes no nest, 
but lays its three or four rotund white eggs in a hole in a 
tree or cliff, amongst a dense cluster of ivy, or even in the 
deserted home of a Crow, a Magpie, or a squirrel. ‘The 
first clutch of eggs is usually laid in March, and succeed- 
ing clutches are produced as late as August. ‘The birds 
resent any disturbance, and are frequently very fearless 
when their young are approached. 
The general colour of the upper parts of the Tawny 
Owl is chestnut-brown, vermiculated and spotted with 
dark brown and black; the wing-coverts are marked with 
round white spots ; the under parts are buff, streaked and 
barred with brown. ‘The female is a trifle larger than the 
male. Bill greyish yellow ; irides dark brown. Length 
of adult between 15 and 16 inches. ‘The nestling is 
clothed in greyish white down. 
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