SPRING MIGRATION lA^ BRITISH AREA 249 



have been describing is actually in progress — long before 

 it ceases — with the advent of March in fact, the northern 

 migration of our summer birds begins. Amongst the 

 veiy first of these spring migrants we must class the 

 Woodcock, which begins to arrive in our area in February, 

 but the migration is strongest in March and April ; 

 another early bird to appear is the Pied Wagtail, that 

 is to say, the individuals that breed with us and winter 

 further south. The Wheatear and the Chiftchaff, how- 

 ever, are the two best known species that indicate the 

 beginning of the exclusively spring migration. Neither 

 of these birds winters in the British Islands normally, 

 but they reach us in March. At first the migration is 

 a weak one, but as April advances the flight becomes 

 stronger and stronger, and wanes gradually again into 

 May. But little migration amongst our typical summer 

 birds, however, is apparent until April. Almost the 

 only species that are seen to arrive in our islands in 

 March are perhaps the two just mentioned, together 

 with the Kestrel, the Ring Ouzel, the Willow Wren, 

 and the Yellow Wagtail. More rarely a very slight 

 migration of the Wryneck, the Stone Curlew, and 

 the Garganey may be observed during March ; but 

 with none of these species does the flight become 

 dominant until April. 



Scarcely without exception the migration of every 

 species that visits the British Islands in summer begins 

 to be apparent some time during this latter month. The 

 most noteworthy exceptions are the Osprey, the Spotted 

 Flycatcher, and the Marsh Warbler ; the two latter 

 species, as we have already seen, migrate far to the east 

 and south of our area. With the advent of April, then. 



