8 THE NESTS AND EGGS OF BRITISH BIRDS. 



England than in other portions of the British Islands, 

 Many rookeries may still be found in towns ; and Lon- 

 don can boast not a few, although they are gradually 

 decreasing in number and extent. 



Breeding habits : The Rook pairs for life. Not 

 only does it continue to frequent the same nesting-sites 

 every season, but it lives in close companionship with its 

 mate throughout the year, and periodically visits its 

 nest trees, as if to assure itself that the home is safe. 

 Tall trees are generally selected for nesting sites — oaks, 

 elms, beeches, horse-chestnuts, planes, and sycamores. 

 Lofty and slender ash and larch trees — mere poles — and 

 in many districts Scotch firs are frequently used. In 

 some rare instances tall holly bushes are selected. As a 

 rule the nests are made in the topmost branches, and 

 very often numbers are built close together, sometimes 

 in large masses. As the Rook is in the habit of adding 

 to its nest each spring, some of the structures are of 

 enormous dimensions, and contain a sackful of sticks 

 or more. In some instances these piles of accumulated 

 sticks have ceased to serve as nests, the owners either 

 being dead or having deserted them. The nest is very 

 firm and compact, made principally of sticks cemented 

 with clay or mud, which latter material usually forms 

 the first or inner lining. This is further lined with turf, 

 moss, wool, dry leaves, bits of straw, and often a few- 

 feathers. It is somewhat shallow, but the lining is 

 remarkably smooth and compact. Both male and female 

 assist in building the nest, and as a rule the birds only 

 work at the task in the morning ; and in the smaller 

 rookeries never remain all night in the trees until the 

 first eggs are laid. Rooks are remarkably noisy and 

 quarrelsome during the building period, and are very 

 prone to steal materials belonging to their neighbours — 

 a practice which often leads to fatal conflicts. As may 



