RELINQUISHING TRAVEL 219 



more powerfully-flying species are more inclined to 

 day migration than the feebler folk; thus, Crows 

 and Swallows among the Passerines, and Geese and 

 Swans among the wildfowl, migrate by day, as do 

 Hawks, Storks, and other powerful and predatory 

 birds. 



The tendency to migration is nearly universal 

 among birds of temperate zones ; even, as re- 

 marked above, in species not usually thought of 

 as migrants, because always visible at any time of 

 year in our country at least ; the most thoroughly 

 sedentary of flying birds being the Game-birds and 

 Woodpeckers, which have special facilities for 

 finding food, though even of these some migrate, 

 such as the Quail and Greater Spotted Woodpecker. 



On the other hand, there is a strong tendency for 

 migrants to settle down and form non-migratory 

 local races ; thus, most of our resident British 

 birds are recognizably different from the conti- 

 nental individuals of the same species which visit 

 us, and are nowadays distinguished as local races or 

 sub-species ; and we may notice that the Blackbird 

 shows a much greater tendency to become per- 

 manently resident in the north than the Thrush, 

 a weaker and less versatile but more strongly-flying 

 bird. The Quail, one of the most anciently-known 

 migrants, often used to pass the winter here when 

 it was commoner, and conversely has been known 

 to breed in numbers in India, usually only a winter- 

 resort, while it has established resident races in 

 Spain and in the Canaries, although attempts to 



