WOODPECKERS 167 



6. It is interesting to inquire by what means the bird becomes aware 

 of the existence of insects or their larvae in the interior of the tree.* It 

 may discover this by means of its eyes (by the worm-holes), or the 

 tappings of the beak may convey some notion of it to the ear. (We can 

 tell by tapping a barrel whether it is empty or full.) It is possible, too, 

 that the sense of smell may give it some indication of the presence of its 

 prey. (We ourselves recognise the presence of several insects by our 

 smell. Give examples.) It is, however, a well-ascertained fact that the 

 tongue of the woodpecker is excellently adapted as a tactile organ. 



ii. Trees provide both its Breeding -place and its Resting-place at Night. 



With its beak the woodpecker hollows out its nest in the trunk of the 

 tree, always high above the ground. (Why ?) It first chisels out a 

 horizontal passage only sufficiently wide to allow it to slip through (why 

 is it so narrow ?), and then excavates the nest-hole, which passes down 

 vertically into the stem. The eggs, which are white (see barn-owl), and 

 incubated alternately by both parents, are laid on chips or powdered 

 wood at the bottom. A similar hole forms the bird's sleeping chamber at 

 night. 



C. Place of the Woodpecker in the Economy of Nature, and its Importance 



to Man. 



From the mere fact that the woodpecker consumes daily large 

 quantities of injurious insects, we may gather its great importance to the 

 forest and to those concerned with its preservation. Naturalists who 

 have carefully studied the life and habits of this bird call it " the real 

 preserver of our forests." It has been condemned for chipping and 

 mutilating the trees ; but it is just for this very act that it deserves the 

 gratitude of the forester, since no other animal is able to the same extent 

 to kill off wood-boring insects, and thus effectually check the increase of 

 these destroyers of our forests. Indeed, the woodpecker never attacks 

 sound trees, since these would furnish no food, but only such as are 

 infested by insect pests. In this way the bird points out to the forester 

 what trees are to be cut down before they are destroyed beyond all hope 

 of being of further use ; and though it hews out its holes for its own 

 benefit, these at the same time form most suitable breeding-places for 

 many song-birds (starlings, tits, redstarts, which are themselves active 

 insect-destroyers). The woodpecker accordingly is doubly deserving of 

 protection ; nor ought we to grudge the bird the small tribute it takes 



* It is extremely difficult to form a correct judgment on the perceptions of an animal. 

 (Why ?) We are invariably tempted to draw comparisons, which may be very erroneous, from 

 our own senses. 



OF THE 



UNIVERSITY 



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