64 



KNOWLEDGE. 



[April 1, 1898. 



WOODPECKERS. 



By Hakey p. Witherby. 



THE woodpeckers (Picida) may be distinguished by 

 the formatiou of the tail and head. The tail 

 would, perhaps, strike the ordinary observer as the 

 most curious part of the bird. It is composed of 

 stiti' but elastic feathers, and is used as a support 



for the body when climbing. The usefulness of the tail is 



seen to best advantage when the bird is pecking, for it then 



uses the tail as a prop to lean upon. This support enables 



the bird to throw its head right back, and then strike or 



hammer the tree with great force, and without losing its 



balance. The woodpecker's head, which is described later 



on, is even more remarkable than the tail. 

 Another peculiarity in the 



anatomy of the woodpecker 



is the small size of the keel 



of the breastbone. This 



dwarfing of the keel permits 



the bird to keep its body 



close to the tree while 



climbing. 



Comparing the breast- 

 bone of a green woodpecker 



with that of a stockdove, a 



bird of about the same size, 



a remarkable dift'erence is 



seen. The stockdove is 



endued with great powers 



of flight, and thus requires 



large pectoral muscles, and 



it possesses a deep keel to 



the breastbone ; while the 



woodpecker, being endued 



with but moderate powers 



of flight, does not possess 



these large pectoral muscles, 



and as it is a climber it has 



the peculiarity of breast- 

 bone mentioned above. 

 The green woodpecker 



(Picus ririiiiK), figured in 



our illustration, is the most 



common bird of the genus 



formd in England. It may 



easily be known from other 



members of the family by 



its plumage, which is of a 



lovely olive green on the 



back, shading to a bright 



yellow on the tail coverts. 



The top of the head is of a 



rich crimson. 



The male differs from the 

 female in having a crimson 

 female has a black one. The peculiar marking, which 

 has earned the name of moustache, is a line of feathers 

 running from the base of the lower mandible under the eye 

 to the end of the skull. 



In common with all others of its genus, the green wood- 

 pecker is possessed of an immensely strong head and beak, 

 admirably suited to the work of hammering trees in search 

 of insects, and boring holes in them for nesting purposes. 



When the bird is climbing a tree it grasps the bark with 

 its feet, and, aided by the tail, proceeds by a series of jerks, 

 always in an upward direction, livery now and then it will 

 be seen to give the tree a tap with its beak, so as to ascer- 

 tain by the sound given out where the tree is rotten. If the 

 bird finds a decaying part in the tree, it continues its blows 



(Irfpn Woodijeckei's; with entv 



' moustache," whilst the 



in order to disturb the insects under the bark, and as these 

 try to escape they are secured with the tongue. Sometimes 

 the bird will tear off a piece of bark while searching for food. 

 The tongue is very curiously formed; it is long and 

 tapers to a hard sharp point like that of a needle, and is 

 furnished at the tip with several hair-like barbs. By 

 means of a very simple contrivance of the muscles of the 

 head, the bird is enabled to project its tongue a great 

 distance beyond the point of the beak. When the bird 

 sees an insect in a crevice of the bark or in a hole into 

 which it cannot put its beak, it thrusts its flexible tongue 

 into the crevice and impales the insect, the barbs preventing 

 it from escaping. Insects captured in this manner form 

 the staple food of the green woodpecker. It occasionally 

 feeds on ants and their eggs, obtained by scraping with its 



feet at their nests. 



These birds have no song, 

 but they utter a harsh 

 mocking noise like a laugh, 

 which may be heard from 

 a good distance, and sounds 

 very uncanny to the unac- 

 customed ear. The laugh 

 is made, as a rule, in the 

 bird's flight, which is heavy 

 and undulating. 



Very early in the year a 

 decayed or decaying tree is 

 chosen for the nest, and tree 

 after tree is attacked until 

 a suitable one is found. 

 Small holes in trees, formed 

 in tliis way, may always 

 be found in localities fre- 

 quented by woodpeckers. 

 The bird, once satisfied with 

 the tree of its selection (fre- 

 quently an old beech), bores 

 a hole some eighteen inches 

 deep into it. The chips are 

 carried away with the beak, 

 while some of the wood- 

 dust, similar to the saw-dust 

 of carpenters, is left at the 

 bottom of the hole. The 

 eggs are laid and the young 

 hatched upon the wood- 

 dust, which takes the place 

 of a nest. Both birds take 

 their turn at sitting. The 

 hole is usually made at about 

 twenty feet from the ground, 

 but I have seen oneiuana?li 

 tree, containing eggs, not 

 more than five feet from the 

 ground. The hole is generally bored into the trunk, but it is 

 occasionally found in oneof the largerbranches. Theeggsare 

 generally five or six in number, and are of a dull ivory white. 

 The young of the green woodpecker, during the first 

 year, may be distinguished from the adult birds by the back 

 being speckled. The whole of the plumage of the young 

 birds is duller than that of the adults. 



Three of the genus Picus are inhabitants of England — 

 the spotted woodpecker (Pints major), the lesser spotted 

 woodpecker (Pici/s minor), and the green woodpecker (P/t!(.v 

 viridis). The habits of the first two are very much the 

 same as those of the green woodpecker described above. 



The black woodpecker (/'/cms iiiartiuv) and the three-toed 

 woodpecker {Pirns tri/tl/ictilus) have been occasionally 

 observed in Great Britain. 



