54 MID-APRIL 
seen them partially build more than one be- 
fore deciding on the one for the eggs. (Com- 
pare the wren, Part I, pp. 82-5.) Crows evi- 
dently provide for eventualities, as they often 
choose isolated wind-driven spots, though 
they do not build so high as rooks, and prefer 
to build against the main trunk of the tree. 
The young, too, are doubtless very active in 
their movements and rough with their claws. 
So altogether the birds make their nests 
strong and heavy. It is said, and [I think 
rightly, that they use the same nest for two, 
three, or more seasons in succession, merely 
doing general repairs and re-lining when egg- 
laying time comes. And no wonder, as the 
structure must require a great deal of labour 
on their part and take a long time to make. 
(I know it took me some time to gather the 
sticks and arrange them for my partially 
built nest, and I did not have to carry up 
each one separately to the top of a high tree !) 
In this case there was no protection for the 
nest from above, but when the elder leaves 
came out they formed a fair roof. 
