But with all his digging and tapping, the sound by which the vicinity of a Woodpecker is most frequently detected, especially in spring and summer, is the unmistakable laughing note which has gained for him the name of 'Yaffle.' No more perhaps than the mournful cooing of the dove does this indicate merriment; it is harsh, too, in tone; yet it rings through the woods with such jovial earnestness that it is always welcome. On such occasions the bird is not generally, I think, feeding, for if the neighbourhood from which the sound proceeded be closely watched, the Yaffle may frequently be observed to fly away, with a somewhat heavy dipping flight, to another tree or grove, and thence, after another laugh, to proceed to a second. It is indeed oftener to be seen on the wing than hunting for food on the trunks of trees. Very frequently too it may be observed on the ground, especially in a meadow or common in which ants abound.
The admirable adaptation of the structure of the Woodpecker to its mode of life is well pointed out by Yarrell. Its sharp, hooked toes, pointing two each way, are eminently fitted for climbing and clinging. The keel of the breast-bone is remarkably shallow; hence, when ascending (its invariable mode of progress) a tree, it is enabled to bring its body close to the trunk without straining the muscles of the legs. Its tail is short, and composed of unusually stiff feathers, which in the process of climbing are pressed inwards against the tree, and contribute greatly to its support. The beak is strong and of considerable length, and thus fitted either for digging into an ant-hill or sounding the cavities of a tree; and the tongue, which is unusually long, is furnished with a curious but simple apparatus, by which it is extended so that it can be thrust into a hole far beyond the point of the bill, while its tip is barbed with small filaments, which, like the teeth of a rake, serve to pull up the larva or insect into its mouth. The Woodpecker builds no nest, but lays five or six glossy white eggs on the fragments of the decayed wood in which it has excavated its nest.
Other names by which this bird is known are Popinjay, Wood-sprite, Rain-bird, Hew-hole and Woodweele.