are Birds Deceitful ?



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Chaffinch nest in a flowering fruit-tree which was clotted over with

pieces of white paper in order to make it look like a cluster of

blossom : unfortunately the genuine bloom would soon fade and drop

away rendering the supposed disguise utterly futile.


Of course many birds do try to hide their nests, and I even

on one occasion had that of the Skylark pointed out to me concealed

by a piece of tangled water-weed loosely attached to one side, so that

it fell over the eggs and hid them from sight when the mother was

from home : the presence of this water-weed at some distance from a

dyke caused me to stoop and examine it closely and thus I discovered

the eggs : whether this was a wilful attempt to deceive on the part

of the bird may be open to question.


As a rule, when a bird is anxious to conceal its nest, it places

it in thick scrub, in dense undergrowth, among ivy or other close¬

growing creepers, or in a hole in a tree, bank, or wall; it does not

artistically examine the surroundings and attempt to imitate them

accurately. A Wren may decide to build its nest in a mass of moss

overhanging a bank, and naturally uses the available material (which

it has pulled out from the centre) in covering the outside of the nest;

or if it builds in a mass of fallen and dead leaves in the midst of a

bramble, it also uses the materials which are at hand ; but although

this renders the nest inconspicuous, I do not for a moment believe

that the little architect is aware of the fact.


Many insects invariably settle for rest upon objects which

best conceal them and are so well hidden that it requires either an

entomologist or a hungry bird to discover them ; but it need not

therefore be assumed that everything which is difficult to distinguish

from its surroundings must necessarily be designed for concealment.


It must also be remembered that man is not the only animal

against which birds would desire to protect themselves ; and when

one considers that, in the case of birds which build open nests

above the ground, the eggs are usually more or less conspicuously

coloured, the advantage gained by a deceptive nest is greatly reduced.

Perhaps this is why natural selection has not made the artificial con¬

cealment of nests by external ornamentation a rule: the advantage

gained is so uncertain that the necessity for it has not been impressed

upon the minds of birds and therefore has not become instinctive.



