THE BIRD AND THE TREE 



case of the wagtails, the yellow may be described 

 as a tree-perching bird ; it can be observed, es- 

 pecially when its young are hidden in the herbage 

 of a neighbouring field, alighting on the topmost 

 boughs of the tall hedge-row very much after the 

 manner of the yellow-hammer. Both the pied 

 and the grey wagtails regularly perch on trees, 

 but they would seem normally to prefer a flat 

 surface, as of a rock or wall, to rest upon. Their 

 feet, indeed, being of lark-like character, are 

 formed to enable them to trip lightly and swiftly 

 upon the level, but plainly lack something of the 

 grasping power by which the tit or finch clings to 

 a slender spray, no matter how rudely it may be 

 swept to and fro by the strongest winds. 



This statement also applies to the wheatear, 

 for although its congeners, the whinchat and the 

 stonechat, will rest securely on the slender support 

 of the telegraph wire, we, personally, have only 

 seen the wheatear take to even the stouter branch 

 of a tree on one or two isolated occasions. It 

 is clear that lark, wheatear, and many other 

 species choose instinctively a surface sufficiently 

 broad to permit the foot and claws to rest flatly 

 upon it, and that any resting place that in- 

 volves a curved grasp is more or less irksome or 

 inconvenient. This is conspicuously true of all 

 the wader clan, and of all birds with webbed feet. 

 Yet numbers even of these unlikely subjects will, 

 on occasion, betake themselves to trees, and it 

 must be noted that some birds — the herons, for 

 example — which seem singularly unfitted by 

 Nature for arboreal life, none the less habitually 

 both perch and nest in branches. 



Of birds of the type of the mallard, the water- 

 hen, and the dipper, although they can hardly 

 be described as even occasional perching birds, 

 still all three, at times, use the tree as a nesting 



129 



