Part 1

Transcriber Notes

Italic text is denoted by _underscores_ and bold text by =equal signs=.

Birds' Nests, Eggs and Egg-Collecting

By R. Kearton, F.Z.S.

Author of "With Nature and a Camera," "British Birds' Nests," "Wild Life at Home," etc. etc.

_Illustrated with 22 Coloured Plates_

Cassell and Company, Limited London, New York, Toronto and Melbourne 1913

First printed _February 1890_. _Reprinted June 1890, May 1893._ New and Enlarged Edition _January 1896_. _Reprinted June 1896, November 1898, July 1900, March 1902, September 1903, July 1905, December 1907, January 1913._

ALL RIGHTS RESERVED

PREFACE

The very kindly reception by the press, and a steady public appreciation, have led to this endeavour to make my little book more complete, by preparing an Enlarged Edition, including all British-breeding birds that have now any reasonable claim for treatment. The work deals with a number of more or less familiar winter visitors that do not stay to breed with us; however, this is perhaps an advantage nowadays, when we all travel much and far.

As mentioned in the preface to the first Edition, this book is not intended to encourage the useless collecting of birds' eggs from a mere _bric-à-brac_ motive, but to aid the youthful naturalist in the study of one of the most interesting phases of bird life. It is to be hoped that the Act of Parliament empowering County Councils to protect either the eggs of certain birds, or those of all birds breeding within a given area, will be of great benefit to many of our feathered friends.

Besides a pretty extensive experience, I have, in the preparation of this work, sought the aid of such excellent authorities as Yarrel (fourth Edition), Seebohm, Dixon, and others, to all of whom I gratefully acknowledge my indebtedness.

R. KEARTON.

Boreham Wood, Elstree, Herts, 1896.

Works by R. KEARTON, F.Z.S., F.R.P.S.

KEARTON'S NATURE PICTURES

THE FAIRYLAND OF LIVING THINGS

BRITISH BIRDS' NESTS

OUR BIRD FRIENDS

NATURE'S CAROL SINGERS

WILD NATURE'S WAYS

WITH NATURE AND A CAMERA

PICTURES FROM NATURE

WILD LIFE AT HOME

THE ADVENTURES OF COCK ROBIN AND HIS MATE

THE ADVENTURES OF JACK RABBIT

STRANGE ADVENTURES IN DICKY-BIRD LAND

Cassell and Company, Ltd., London, New York, Toronto and Melbourne

BIRDS' NESTS, EGGS, AND EGG-COLLECTING

INTRODUCTION.

=The Problem of Preservation.=--As a rule the first subject to which the young naturalist turns his attention is the most interesting one within his reach, and that subject is undoubtedly found in bird-life; particularly that portion of it which concerns the nests, eggs, young, and various modes of nidification, for this is really the kernel of ornithology. Its details teach him the utility of systematic study and close observation, two important points in all matters of scientific research.

It is my intention in the following pages to furnish as full and interesting particulars on Oology, which may fairly be entitled to the dignity of a science, as can be found, or is likely to be required, in any popular treatise of its modest compass.

This particular branch of natural history has been until lately but indifferently studied--in fact, considered unworthy of higher attention than that which could be bestowed upon it by schoolboys. People have been content to know that the wonderful architecture and mechanism of a bird's nest was the outcome of a force vaguely known as _instinct_, without taking the trouble to discover its workings, extent, or limits.

Instinct is an extremely difficult power to define, and whether it be described as "hereditary habit," or simply accepted as an unknown law of Nature blindly followed by its possessor, it cannot be denied that it is the outcome of conditions, and always amenable to them. If the word mystery were often substituted for instinct, it would not be at all out of place, for it means quite as much. It is more honest to acknowledge our ignorance than to fence it round by speculative theory or cover it by almost meaningless phrases. Survival of the fittest is undoubtedly Nature's great law. With this end in view she governs and regulates the actions of birds in exactly the same way as she controls the colour and character of their plumage, shape, size, tint, and number of their eggs, first movements of their young, and other peculiarities we do not understand.

If we grant that birds possess highly-developed imitative faculties and tenacious memories, with a discriminating power which enables them to adapt certain habits of life to surrounding conditions, even this fails to explain a great deal. Supposing it is the secret of their beautiful nest-building, the house sparrow adopting trees to nest in where the houses are built of brick and lack crevices, or the falcon deserting its usual high inaccessible crag and nesting on the ground; it cannot possibly account for a young duck taking the water directly it has left the shell, or the habit of young plovers, snipes, grouse, and other birds crouching flat when danger is overhead even as soon as they are hatched. A stronger point still is migration, for birds cannot return to their old haunts by a memory of landmarks, as pigeons do even in their longest flights, for they fly over immense bodies of water and traverse vast tracts of land by night, on wings the length and strength of which have been specially developed for such long flights. Some fly across great stretches of country, yet are never seen except at the points from which they start and finish their flight. Neither can these journeys be performed always under the guidance of leaders, for all migratory birds do not travel in flocks.

I will endeavour to point out how Nature has solved the problem of preservation; and it is equally interesting whether by the self-governed action of the bird, or the blind following of an impulse known only as instinct. Because we are unable to find any protective colouration in the plumage of a bird, its eggs or nest, we must not conclude that such peculiarity is a mere accident or useless decoration, for it either serves some wise end unknown to us, or has done so in far past ages, and is perpetuated because its possession is not distinctly harmful, and may at some future date be again called into requisition against danger. The extinction of nearly all birds whose existence is reasonably well-known has not been due to natural causes, but to man or the influence his civilisation has introduced. Nature never made such a mistake as the introduction of rabbits and sparrows into Australia. They are two potent forces turned loose into practically unrestricted space, without any of their natural limiting influences.

=Protective Colouring of Birds.=--The protective colour of the plumage of certain birds is the great source of their safety during incubation. For instance, birds which nidificate on the ground, such as Black and Red Grouse, Pheasants, Partridges, and Sandpipers, all subject to the depredations of winged and creeping enemies, are preserved by the modification of their tints. The same means of security attend their eggs and downy young, even the extreme simplicity of their nests aiding the escape of detection. Birds whose down has protected them during the early part of their history, become aware of the dangers which threaten a more conspicuous plumage, which is a marvellous thing, whether acquired by reasoning or instinct. This is proved by the action of birds of the same order. The Golden Plover, with plumage in harmony with the surroundings of her nest (her feathers being still further subdued in colour during the breeding season), sits much closer than the Green Plover, although a shyer bird, with eggs possessing the same protective qualities. The Green Plover knows her plumage is much more conspicuous than her eggs, and quietly slips away before danger approaches half so near as the golden plover will allow it.

I am surprised to find so great an authority as Darwin assert that "the species which represent each other in distinct countries will almost always have been exposed to different conditions, but we can hardly attribute to this action the modification of the plumage in the males alone, seeing that the females and the young, though similarly exposed, have not been affected."

Possibly such may be the case where no protective modification is necessary in the female or young; but what about the fact that female Red Grouse differ much in the colour of their plumage, according to the conditions under which they live, though the males are left totally unaffected? Instance the female Grouse, known as the "Moss-hen," always found on the highest and most exposed situations where there is little cover, consequently great need of harmonising colours: a strong point, I venture to assert, in favour of protective utility.

Moulting has been rendered subject to the law of preservation in a remarkable degree, for where birds are open to periodical changes of surrounding conditions which materially affect their existence, they are provided with an extra moult. For example, the Ptarmigan's plumage is pure white for winter snow, and brown for summer heather.

The stoat's fur undergoes a similar change of colour; and more marvellous still, to pursue the preservation argument into the water world, take a common trout, and chase him up and down a shallow pool until he has become thoroughly scared, and it will be found that wherever he rests for a few seconds his colour will change in obedience to that of the bed of the stream directly beneath him; so much so that I have known one half of a trout very dark and the other half very light coloured, correspondingly with objects beneath and around him.

Again, the same high authority points out that "the feathers of young birds are in male and female similar to the female parent when she is of a dull colour, but like the male when he is dull and the female bright; also, when both parents are of a conspicuously bright colour the young take a dull colour of their own"--for example, Robins. He infers that these colours represent those of far distant progenitors; but as safety lies in these modified tints, and preservation being Nature's chief problem, it is more reasonable to suppose that Nature lends this means of protection whilst the bird is in its most helpless condition, for an evolution that tends to increase dangerously conspicuous colours would only seem to invite extinction.

In another place he says "it deserves especial attention that brilliant colours have been transferred much more rarely than other tints." Yes, simply because they are generally a source of danger to the possessor.

Three familiar instances of special modifications in the plumage of the female are to be found in the black grouse, pheasant, and blackbird, all nidificating in situations more or less fraught with danger. Remarkable again is the fact that where the female is more conspicuously marked than the male the latter takes upon himself the duties of incubation entirely, or renders a great deal of aid, which is strong proof that dull subdued colours have been adopted for the preservation of the young in their several stages of helplessness.

=Protective Construction of Nests.=--It is surprising again to find Darwin, in arguing that few British birds build covered nests to protect themselves against the conspicuousness of their own colours, citing the Dipper as an instance of this. But what about the white breast of this bird, which marks it out at long distances against the dark rock or water? Again, her pure white eggs are manifestly a source of danger, more conspicuous even than the bird. It must not be supposed I overlook another important feature in the covered nest of this bird, which is, however, subservient to the bird's desire to hide her white plumage and eggs, which renders it equally preservative in character. The bird generally builds near a waterfall, often quite behind, undoubtedly for the safety this situation affords, and she is not only obliged to construct a covered nest, but one which must keep out the constant dripping of water percolating through fissures in the rock. The construction of this nest even cuts off the chance of a stray splash of water finding its way to the eggs or young during the parent bird's absence, by the peculiarly ingenious entrance she makes to her little home.

Still further, where birds are conspicuous in colour they either build covered nests, or place them in such situations as afford safety, and are thus equivalent. For instance, the Woodpecker, Kingfisher, and Magpie, the two former having a double object in the selection of a situation, firstly their own eminently brilliant colours, and secondly their pure white eggs. The latter building a covered nest of such materials as thorns, seems to point to a strategic planning against the immorality of the family to which he belongs.

=Periods of Incubation and their Utility.=--The Duck family all lay eggs white, or nearly approaching it, and take the precaution to cover them carefully on leaving the nest.

Some naturalists have been of opinion that this is to prevent an undue escape of the heat generated by the parent; however, I am unable to find any observations to prove that these birds leave their eggs for feeding purposes longer than any others that hatch their young in three weeks. Neither does it appear that they transmit heat better or worse than birds of entirely different habits, for it takes a Fowl four weeks to hatch a Duck's egg, and a Duck will on the other hand hatch a Fowl's in the normal time, three weeks. It appears that the period of incubation is regulated with a great amount of precision by the contemplated habits of life, the difficulties to be overcome, and dangers to be endured, as the following facts show:--

A Pigeon hatches its young out in sixteen days, and by a special process and careful assiduity feeds them until they are almost full grown. A Fowl, though not capable of feeding her young in the same way, possesses the power of defending her offspring, finding and selecting suitable food, and attending to their education generally in a higher degree than the Duck can bestow on her progeny, which take four weeks to hatch.

To still further illustrate this wonderful regulating principle, let us diverge for a moment from the eggs of birds to those of fish, where we find things adapted with incredible precision to the surrounding conditions of existence. I have noticed that trout living and being obliged to deposit their ova in a stream subject to great variations of temperature, spawn much earlier than trout in a stream preserving a comparatively even temperature. The condition of the latter in comparison with the former showed unmistakably that the difference of food supply did not account for it, and as the fry in both streams appeared about the same time in the spring, and exhibited no appreciable difference in size or strength during the summer, the natural conclusion to be arrived at is that the time required for hatching in each stream is contemplated and provided against in some mysterious way.

=Mechanical Construction of Eggs.=--We now come to another phase of the protective principle, even more remarkable than those we have already discussed, and equally useful. This is in the mechanical construction of eggs to suit their situation and surrounding conditions. What an admirable provision Nature has shown in placing the axis of a bird's egg just where it will prevent it rolling off a flat surface, such as a ledge of rock, when moved by the terrible gusts of wind that sweep over high latitudes, or perhaps roughly moved by the parent bird suddenly fluttering off when scared.

Take, for example, the egg of the Guillemot. This is so wonderfully constructed that if moved it will not roll away like a marble or billiard-ball, but simply spins round on its axis, in the same way as a screw or top, showing a wonderful adaptability to the exposed situation chosen by this bird for incubation.

Birds which make round, cup-shaped nests or incubate in holes, such as the Owl and Kingfisher, for instance, lay round eggs, which run no risk of rolling away and being smashed. Their shape also facilitates alteration of position of the parent bird to secure an equal distribution of warmth and ventilation.

Were the Guillemot and either of the latter birds to change nesting situations for a while, it is probable a speedy extermination of the species which adopted the flat rock for the round egg would soon take place, affording a beautiful illustration of the power that is also guiding the action of birds under the mysterious name of instinct. It is an unknown and unknowable power, yet its workings are as undeniable as its results.

As a further illustration, let us take the eggs of the Golden and Green Plovers, and consider for a moment their size, shape, number, and colour.

All these qualities serve some well-defined and demonstrably useful end. Firstly, their size is abnormally large compared with that of the layer, but this is a provision which supplies the necessary size and strength of the young bird to enable it to cope with the surrounding conditions of its first days of self-feeding and locomotion amongst coarse grass and other obstacles.

Secondly, the shape of the egg serves to economise space, an important point where the eggs are large and the bird small. Thus the four pear-shaped eggs, having their small ends all pointing to a common centre, practically form a square, and thus enable the bird to cover them all at the same time.

Thirdly, the number of eggs is always four, and by such limitation the form of the square is preserved, and the difficulty of a small bird covering a number of large eggs satisfactorily surmounted. I have often disarranged the order of Plovers' eggs, but always found that the first thing done by the bird on her return was to reduce chaos to order by turning the round ends out and the small ones into the centre of her little household.

Lastly, we come to the beautiful harmony of colouring of the eggs with surrounding objects, rendering them often very difficult to find, even by a practised eye, and the scant nest still further aiding in the chances against discovery.

The Sandpiper affords an admirable instance of the assimilation of its eggs to surrounding objects, and the extreme difficulty experienced in finding them attests to its protective utility.

=Why Eggs Vary so much in Point of Number.=--The number of eggs laid by birds of different orders seems to be regulated by the danger to which they are exposed and the amount of food which the parents will be able to supply.

Thus, the Eagle in its inaccessible eyrie enjoys almost perfect immunity from danger, and has only two young ones, for which, however, the supply of food is only equal to the demand, and it is probable that one more voracious appetite would seriously endanger the safety of the whole family.

On the other hand, take the Common Partridge with its sixteen or twenty eggs, the high percentage of its dangers, and the generally abundant supply of food.

Again, the Swift, on its untiring wings for sixteen hours a day, avoids the majority of dangers which threaten less favoured birds, and only lays two eggs, in a position very few other birds could adopt, yet one which secures her little household the amount of safety necessary for the due survival of the species. However, with her limited family, dexterity on the wing, and enduring powers, she seems to have no leisure time during the period her young require feeding. As an opposite, take the House Sparrow, with its five or six eggs, innumerable dangers, and easy access to food, and it must be confessed these things are ordered by a power of infinite wisdom.

=Curious Nesting-Places.=--The general situation and locality in which each bird's nest is likely to be found are mentioned in dealing with the bird under its separate heading; however, it may not be uninteresting to chronicle a few of the most remarkable and well-authenticated departures from accepted rules.

I have myself found a Dipper's nest on the branch of a tree twelve or thirteen feet from the water and twenty from the bank. This nest was of ordinary shape and size, its material being of the same kind as others, and securely fastened amongst the prongs of the branch like a Missel Thrush's. When the parent bird was disturbed she dived into the pool below to make her escape (a habit invariably adopted when nesting in an ordinary position). She reared her young in safety, however, in spite of the awkward situation she had selected, and I have every reason to believe got them off without mishap. I have also found a Thrush's nest on the ground, precisely in the position a Lark selects.

House Sparrows furnish many examples of curious situations adopted for incubatory purposes. Not long ago a pair of these birds built their nest, and successfully hatched a brood, in the cartridge-box of a cannon which was fired twice daily in the Gun Park at Woolwich. It is a notable fact that in some parts of the country Sparrows build extensively in trees, whilst in others such a circumstance is unknown. Some ornithologists are of opinion that it is an hereditary habit, others supposing that it is resorted to for the sake of coolness in hot weather; but a reason I incline to is that in parts of the country where houses and out-buildings are made of stone the birds find ample accommodation in joints, crevices, and crannies where the mortar has been dislodged, and are therefore not driven to the necessity of adopting trees, like birds found in districts where the houses are made of bricks, consequently closer, and affording less opportunity for nest-building. This bird, besides its noted pugnacity, is an arrant rogue, and invariably takes advantage of the House Martin's labour. I have known a house with twenty nests all close together under its eaves, about half of which were occupied by Sparrows, which had, in some cases where the nests were new, been actually watched ejecting the eggs of the original owners.

The Robin is noted for its caprice in the selection of a nesting site, and has been found hatching its eggs in nearly every conceivable situation, from the ordinary mossy bank to the pocket of a gardener's old coat which had been hanging undisturbed for several weeks in a tool-house. Old kettles, water-cans, inverted plant pots, &c., in buildings close to machinery in daily motion, and other equally curious places, are by no means rare occurrences. A case is recorded of a Robin's nest having been built in the hole made by a cannon-ball through the mizzen-mast against which Lord Nelson was standing when he received his death-wound on board the _Victory_.

Swallows have also been known to adopt quite foreign situations for breeding purposes, such as holes in trees, and even openly on the branches.

Cases are known of the Starling building its nest down holes in the earth, and also quite exposed in trees, similar to the nest of the Sparrow. It has also been found going shares with a Magpie.

The Pied Wagtail occasionally chooses strange quarters, one case being on record of a pair building beneath a railway switch, over which trains passed nearly every hour in the day within a few inches of the nest.

The roof of a house in Hull was once selected by two pairs of Rooks for nidification, and proved a successful choice, for they managed to build nests and rear their young.