FOR NORTHERN INDIA 160 



the other non- migratory : the steppe-eagle 

 and the tawny eagle, the large Indian and the 

 common kite, the long-legged and the white- 

 eyed buzzard, the sparrow-hawk and the shikra, 

 the peregrine and the lugger falcon, the com- 

 mon and the red-headed merlin, the kestrel and 

 the black- winged kite. 



It is tempting to formulate the theory that 

 the raptores are migratory or the reverse 

 according or not as they prey on birds of 

 passage, and that the former migrate merely 

 in order to follow their quarry. Certain facts 

 seem to bear out this theory. The peregrine 

 falcon, which feeds largely on ducks, is migra- 

 tory, while the lugger falcon a bird not 

 particularly addicted to waterfowl remains 

 in India throughout the year. 



The necessity of following their favourite 

 quarry may account for the migratory habits 

 of some birds of prey, but it does not apply 

 to all. Thus, the osprey, which feeds almost 

 exclusively on fish, is merely a winter visitor 

 to India. Again, there is the kestrel. This 

 preys on non-migratory rats and mice, never- 

 theless it leaves the plains in the hot weather 

 and goes to the Himalayas to breed. All the 

 species of birds of prey cited above as migra- 



