338 THE BIRDS OF THE BRITISH ISLES. 



Strike a wounded bird with his stick, killing it before he 

 attempts to pick it up, because in its struggles it litters every- 

 thing with these easily shed feathers, and there are good 

 retrievers which will not pick it up, having once experienced 

 the unpleasant mouthful. Though some immigrants arrive in 

 October, the biggest hordes come in during the next three 

 months, and often return again in February. Fortunately the 

 numbers vary in different years and the localities attacked are 

 widespread, for a Wood-Pigeon invasion is a menace to food 

 supply ; the numbers sometimes observed coming in from the 

 North Sea are beyond all calculation. Much grain is devoured- 

 by the greedy bird — 838 grains were counted from one crop — 

 but acorns are its great stand-by ; in years when the acorn 

 crop is large, immigrants are most abundant. Beech-mast, 

 nuts, haws, berries, young leaves of ash, beech, and oak are 

 amongst the harmless foods ; turnip-tops, young greens, 

 Brussels sprouts, small potatoes, crops which it damages ; but 

 by devouring seeds of charlock, ragwort, and other weeds it 

 does some amount of good. The crops of birds have been 

 found full of caterpillars of the dotted border and mottled 

 umber, both defoliating species, and certainly at times it eats 

 harmful slugs. 



The nest (Plate 151) is a flimsy platform of intertwisted sticks, 

 through which the light shows, and the eggs may be seen from 

 below ; it is built in a tree or hedge at varying height from the 

 ground ; exceptionally it is on the ground or on a ledge. The 

 two eggs are dead white and glossier than those of the Stock- 

 Dove ; they measure about r6 by 1*2 inches. Winter eggs 

 have several times been found, but from April onward is the 

 usual time ; two or even three broods are reared. The nestling 

 or squab has sparse yellow down, and a broad, soft bill, the 

 lower mandible broadest ; it pushes its boat-shaped bill into 

 that of the mother bird and sucks up the milky fluid she 

 provides for its early nourishment. 



