552 BRITISH BIRDS. 



in winter^ when almost starved by a long-continued frost, lie will often 

 bore into the turnips with his strong beak. Perhaps the most favourite 

 feeding-grounds of the Rook are the stubbles, especially when ploughing 

 is going on and worms and grubs are to be found in the newly turned up 

 soil. When feeding, the Rook is very wary, and a sentinel is usually 

 perched on some neighbouring tree to give the alarm on the approach of 

 danger. Towards evening, when their appetites are satisfied, they often 

 fly round and round, and toy with each other in the air, before setting off 

 for their roosting-quarters. 



Towards the end of February they begin to repair their nests. Every 

 day they stop longer and longer ; and when the eggs are laid they roost at 

 the rookery. Rooks may be tempted to form a new rookery, by putting 

 up artificial nests in suitable trees. During the process of building they 

 are often very quarrelsome. When the birds break off twigs fi-om the 

 nesting- trees, they fly clear of the tree and gain the nest by an uninter- 

 rupted course, probably because, were they to convey the twig through 

 the tangled branches, it would be an extremely troublesome and difiicult 

 task. During the building-period one of the birds usually stays to guard 

 the unfinished nest whilst its mate is seeking materials ; for Rooks are 

 pilfering birds ; but when once the nest is completed it may be left 

 with safety. When I was residing at ShefBeld I had several Rooks' nests 

 in my garden, my next-door neighbour had fourteen, and there were about 

 as many more on the other side of the road — all no doubt forming part of 

 the old rookery in Broomhall Park, which must originally have been 

 scattered over a mile or more, as there are isolated trees left in the streets 

 which are still tenanted with their old occupants every spring. Towards 

 the end of February the Rooks began to be very busy about their old 

 nests. One year only one nest had survived the storms of winter. The 

 birds appeared to have a quarrel about it ; and finally it -was completely 

 pulled to pieces. They fairly began to build in good earnest about the 

 1st of March, when they might be seen, sometimes three or four in a tree 

 at once, tugging at the twigs and breaking off a piece, which they often 

 transferred from their beaks to their claws, apparently to rest from the 

 exertion of breaking it off. They seemed to be very quarrelsome all the 

 time they were building, continually stealing twigs from each other's 

 nests. Once they fought so desperately that one poor Rook fell down 

 dead. It was no uncommon thing to see a good foundation for a nest 

 laid by breakfast-time, and to find not a vestige remaining at noon. Both 

 parents assist in the duties of incubation ; and Dixon assures me that he 

 has repeatedly seen them change places on the nest. 



The nest is composed outwardly of sticks, varying in thickness from 

 slender twigs to branches more than half an inch in diameter, and is 

 cemented with mud and clay and lined with large masses of turf, a few 



