88 STUDIES IN BIRD-MIGRATION 



so as regards the western coasts. The first movements 

 from the summer haunts are towards the coasts, which 

 are reached by many local routes, especially along the 

 courses of rivers and their tributary streams. 



When the east coast is reached, the emigrants skirt 

 its shores and their vicinity, proceeding southwards 

 usually by easy stages, and gathering strength as they 

 advance, particularly at estuaries and river-mouths, such 

 as the Tay, Forth, H umber, Wash, Thames, etc. They 

 finally leave our southern shores by the same routes 

 along which they travelled to reach them in the spring. 



The western emigratory movements are not so 

 simple in their geographical aspects. Here we have the 

 Hebridean and other isles, Ireland, and the Isle of 

 Man, and the numerous firths, sounds, and estuaries 

 of the mainland exercising varied influences. The routes 

 followed by these departing summer birds are the same 

 as those already indicated for the spring movements of 

 the birds of passage, but the direction is the reverse, 

 — i.e.^ to the southwards. The Outer Hebridean summer 

 birds move towards the north-west coast of Ireland, 

 some of them by way of Skerryvore, while others even 

 traverse St Kilda. Those leaving the inner isles 

 proceed by Dhu Hearteach and I slay, towards the 

 mainland at Can tyre, whence they probably travel along 

 both sides of the Irish Sea. The eastern section of 

 this migratory stream skirts the west coast of Britain, 

 and receives in its course considerable tributaries from 

 the Clyde basin, Galloway, the Solway, the Isle of 

 Man, Wales, and the Bristol Channel. From the 

 Pembroke coast southwards very important additions 

 are received from Ireland. Finally the south-west 

 coast of England is reached, between the Scilly Isles 



