MARSH WARBLER 



districts than is sometimes imagined to be the case, but, 

 according to my experience, is gradually extending its range in 

 a northerly direction. It is now eleven years since the bird 

 first came under my notice on the northern boundary of the 

 county of Worcester. A solitary individual then appeared 

 in June, but after remaining a few days vanished. For some 

 years following there was no further sign of the species, but 

 it has now reappeared and, I hope, finally established itself in 

 the district. There are places in both Worcestershire and 

 Gloucestershire where it can by no means be described as 

 uncommon, since it is an annual visitor in numbers which seem 

 to be increasing. The Severn Valley appears to be especially 

 favoured, but in saying this we must bear in mind how limited 

 our knowledge of its distribution may really be, and how rare 

 the bird was supposed to be until efforts were made to discover 

 it. Many districts in which it has already been found nesting- 

 are eminently suited to its habits, and it is difficult to believe 

 that in such places it is a casual visitor only. But just because 

 it is an easy matter to assume that it has been overlooked, we 

 must in the future scrutinise all the facts relating to its dis- 

 tribution the more closefy, for otherwise we should be neglect- 

 ing the bird with the most striking and highly developed vocal 

 powers of all our birds. The gradual extension of its breeding 

 range has a meaning in relation to the struggle for existence 

 which we can scarcely afford to ignore. On migration it has 

 been recorded from St. Kilda and Fair Isle. Concerning its 

 distribution in the Iberian Peninsula little appears to be known 

 beyond the fact that it is said to have bred towards the south, 

 though the evidence is far from satisfactory. In France it is 

 generally distributed, except in the western provinces. In all 

 suitable localities in Belgium, the Netherlands and Germany 

 it is common, but in Denmark scarce : it has occurred near 

 Gothenburg. To the northern provinces of Italy, especially 

 Piedmont, it is a common summer visitor, and though less 

 common than the Eeed Warbler in Switzerland, it is neverthe- 

 less generally distributed in all suitable localities, such as the 



3 



