NESTLESS BIRDS AND ANNEXERS 47 



two groups, the Birds of Prey and the Owls, and of 

 course it is by no means a universal one in these. 

 Here again w^e are confronted by widely differing 

 methods of nidification amongst what are obviously 

 closely allied birds. We find species failing to make 

 any provision of their own for their eggs, notwith- 

 standing the fact that so far as we can judge they 

 are just as well able to build a nest as their more 

 thoughtful or industrious relations. One or two 

 instances selected from well-known species must here 

 suffice to illustrate this peculiar trait. One of the 

 most familiar of these is the Kestrel. It has been 

 stated by more than one writer that this pretty little 

 Haw^k occasionally makes its own nest, but this I do 

 not for one moment believe. If it cannot find a 

 suitable deserted tenement it lays its eggs upon the 

 bare earth or rock in some crevice of the cliffs, or 

 even in a hole in a building or a tree trunk. Indeed 

 there can be no doubt that many pairs make such a 

 selection from choice and not from necessity. In 

 such a spot no nest is ever constructed, but as the 

 breeding season progresses numbers of pellets or 

 castings accumulate in the place and often surround 

 the eggs. But it is as an annexing species that we 

 are now considering the Kestrel. The bird generally 

 selects the deserted home of a Crow, a Magpie, or a 

 Sparrow Hawk, less frequently the old nest of a Ring 

 Dove or even the drey of a squirrel. The Hobby is 

 another annexing species. Unfortunately the British 



