BRITISH WARBLERS 



ground between the two territories was, so far as one could 

 judge, suitable in every respect for nesting purposes, yet 

 it was passed over in rapid flight. 



The daily routine of a male before the arrival of a female 

 is simple enough, most of his time being spent in fluttering 

 backwards and forwards between two particular trees. The 

 males of many species have a peculiar flight of their own 

 during the period of sexual activity, which alone makes 

 recognition possible, and the male Wood Warbler must be 

 reckoned amongst this number, for his slow progress between 

 two favourite points, accomplished by moderately quick though 

 short beats of the wings, is strongly characteristic of the 

 species. The two other species — the Willow Warbler and 

 Chiff-chaff, which we know well in this country, and to which 

 the Wood Warbler is closely related — have no flight exactly 

 comparable with this; but just as they have some special 

 tree, or group of trees, which they make use of more 

 frequently than another, and seem to regard as a head- 

 quarters, so this bird has two separate points with a highway 

 connecting them. The song too forms an important part of 

 this particular aspect of behaviour, since at no other time 

 is it uttered so frequently or so regularly. But we do not 

 find the bird always thus employed. There are periods of 

 varying lengths when it is engaged in searching for food 

 high up in the tree tops or low down amongst the bushes, 

 and it is just at these times that it roams farthest from its 

 central position, and, journeying thus, forms a habit which 

 justifies the application of the term "boundary" to the normal 

 limit of its wanderings. In the districts in which my 

 observations have been made, the birds are plentiful enough, 

 though not nearly so numerous as the Willow Warbler or 

 Chiff-chaff ; so that the conditions which lead to overcrowding 

 and competition have never beeu very present to my 

 experience. I have never, that is to say, witnessed much 

 rivalry between different individual males, but sufficient all 

 the same to show that they are just as anxious to defend 



