34 STUDIES IN BIRD-MIGRATION 



certain birds are observed throughout the year they are 

 not necessarily represented in summer and winter by the 

 same individuals, for the place of those which have 

 passed the summer here is often taken in winter by immi- 

 grants from other areas, mainly from continental Europe. 



The ordinary observer, until lately at least, never 

 thought birds usually considered residents were repre- 

 sented in our islands by a sedentary and a migratory 

 race. 



Local British Movements.- — In addition to the 

 important migrations between the British Isles and 

 the more or less far-off lands to the north, south, 

 and east of them, much migration takes place in 

 spring, autumn, and winter between various portions of 

 the British area. These local movements are under- 

 taken in spring to reach nesting haunts from winter 

 quarters near at hand or somewhat far removed. In 

 autumn the summer homes are quitted and a return 

 made to winter retreats. In some cases these move- 

 ments are from Great Britain to Ireland — the Sister Isle 

 beinor the winter home. There are also smaller local 

 winter movements, but these will be alluded to in another 

 section. Thus there are innumerable minor migrations 

 between all the parts of the British area, and hosts of 

 Sea-Fowl on quitting the rocky fastnesses, in which 

 the summer has been passed, spend the winter in the 

 neigfhbourino^ seas. 



Winter Visitors.^ — In the autumn a great change 

 takes place in the bird-life of our islands. The summer 

 guests gradually slip away, and another set of birds, also 

 seeking winter quarters, arrives from Northern and 



' For a list of the British Winter Visitors, with an indication of their 

 summer haunts, see page 50. 



