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LIST OF ILLUSTRATIONS

A Seal's Dormitory Photogravure Frontispiece
Bird Sympathy Facing page 42
From the Rocks of Raasey Isle " 84
On the Edge of the Precipice " 92
Aerial Piracy " 133
A Seal's Plaything " 216
A Perilous Journey " 288
"One More Unfortunate" " 308
"Nature Red in Tooth and Claw" " 316
Polite but Insistent " 346

THE BIRD WATCHER

IN THE SHETLANDS

WITH SOME NOTES ON SEALS

—AND DIGRESSIONS

CHAPTER I

MY ISLAND AGAIN!

M

MY island again!—and all the birds still there, looking just as they did when I left it. More, too, have come. At night, but in a sort of murky daylight, I walk over the breeding-ground of the terns, a long flat strip of pebbly beach—or rather the heather a little way above it, for on the beach itself they do not appear to have laid. Rising, all at once, as is their wont, they make a second smaller canopy, above me, floating midway beneath the all-overshadowing one of dreary low-lying cloud. Out of it, ever and anon, some single bird shoots down, with a cry so sharp and shrill that it seems to pierce the ear like a pointed instrument. Occasionally an oyster-catcher darts in amongst them all, on quickly quivering wings, its quavering high-pitched note of "teep, teep!—teep, teep, teep!" threading, as it were, the general clamour, whilst like a grey, complaining shadow, the curlew circles, beyond and solitary, shunning even the outer margin of the crowd. How lonely is this island, and yet how populous! The terns—a "shrieking sisterhood"—make, as I say, a canopy above me, when I pace or skirt their territories; but what is that to the great perpetual canopy of gulls that accompanies and shrieks down at me, almost wherever I go? Were it beneath any roof but that of heaven, how deafening, how ear-splitting would be the noise, how utterly unendurable! But going forth into the immensity of sky and air it sounds almost softly, harsh as it is, and even its highest, most distressful notes, sink peacefully at last into the universal murmur of the sea, making the treble to the bass of its lullaby.

Most of the cries seem to resolve themselves into the one note or syllable "ow," out of which, through varied tone and inflection, a language has been evolved. "Ow-ow, ow-ow, ow-ow!" sadly prolonged and most disconsolately upturned upon the last, saddest syllable—a despair, a dirge in "ow." Then a series of shrieking "ows," disjoined, but each the echo of the last, so that when the last has sounded, the memory hears but one. Then again a wail, intoned a little differently, but as mournful as the other. And now a laugh—discordant, mirthless, but a laugh, and with even a chuckle in it—"ow, ow, ow, ow, ow!" the syllables huddling one another like the "petit glou-glou" of water out of a bottle. All "ow" or variants of "ow," till the great black-backed (the bulk are herring-gulls) swooping upon you, almost like the great skua itself, breaks the spell with a "gugga, gugga, gugga!" or, right over your head, says "er" with a stress and feeling that amounts almost to solemnity.

How lonely and yet how populous! Does life, other than human life, around one, in any way diminish the sense of solitude? I do not think it does myself, except through human association, and for this, human surroundings are more or less requisite. Thus woodland birds seem homely and companionable in woods near which one has a home, and gulls upon the roofs of houses take the place of pigeons or poultry in the feelings they arouse. So, too, as long as a natural alacrity of the spirits prevails over that dead, void feeling which prolonged solitude brings to the most solitary, the wildest creatures in the wildest and loneliest places may seem to cheer us with their presence. But the feeling is a false one, dependent on that very condition, and treacherously forsaking us—even to the extent of making what seemed a relief, an accentuation—when it fails. How often, as I have wandered over this little, noisy, thickly crowded retreat, has all the fellowship around me served but to remind me of my own exclusion from it—as from that of fairies, ghosts, elementals—but what all this life could not do, the cheerful firelight on the bare stone walls of the solitary shepherd's hut did at once for me, and with bacon in the frying-pan I had all the companionship I wanted. A dog—one's own or that knew one—or even a cat, might do more by its own personality than such inanimate objects by association merely, to relieve the sense of solitude; but no quite indifferent creature could do as much, I believe, or indeed anything.

But with the gulls here—and still more with the terns—there is more than mere indifference. It is a disagreeable reflection that all these many birds—these beings everywhere about one—resent one's presence and wish one away, that every one of all the discordant notes uttered as one walks about under this screaming cloud of witnesses has a distinct and very unflattering reference to oneself, upbraids one, almost calls one a name. To be hated by thousands—and rightly hated too! It is strange, man's callousness in this respect—that he should see his presence affect bird and beast as that of the most odious tyrant affects his fellow-men, yet never sleep or eat a meal the less comfortably for it! So it is indeed—and the principle holds good as between races and classes of men—when one has one's fellow-tyrants to laugh and joke and chat with; but here, with but oneself and one's own thoughts, the hostility of all these gulls begins to trouble one. There is no one to share in the obloquy—it falls upon you alone. You are the most unpopular person in the island.

I get another odd sensation through being here. Gradually, as the days go on, it seems more and more as though gulls made all the world, and this feeling, which, for its singularity, I value, I can encourage by seeking out some spot from which the sight of all but them and inanimate nature is, with extra rigour, shut out. The centre of the island, which is the gulls' especial sanctuary, presents these conditions. It forms an extended grassy basin, ringed in with low, swelling peat-hills, above which—for the intervening space is invisible—rise the tops of hills far higher, belonging to islands of some size which lie spread about this little one, hiding it from all the world. Through dips in these, and in the rim of one's own brown basin, one gets the sea—dull, cold grey lakes of it, engirt by dimmer islands, far away. No human sight in it all; no sail, for hours, upon the sea—only the gulls which, in their thousands and their all-possession, seem to have subdued the world. Men are gone, and gulls now take their place, become ennobled for want of a superior. Like snowy-toga'd Roman senators, they stand grouped about, or walk over the grassy amphitheatre—their natural senate-house—and it is wonderful with how slight an effort of the imagination—or indeed with none—the dissonant cries and shrieks, the clang and the jangle, become as the dignified utterance, eloquent oratory, to which one has sat and listened, spell-bound, in the gallery of the House of Commons. "Such tricks has strong imagination." "How easy," indeed, as Shakespeare tells us, "is a bush supposed a bear!"

It is curious how the gulls cling to their breeding-places long after the breeding-time is over. Summer—or say July—is now fast waning, yet in the way they stand amidst the heather, rise as I approach, and float, shrieking, above me, it is just as it was last time I was here, which was in early June, when things were hardly more than beginning. Any one not knowing the time of the year—and it is difficult to tell in the Shetlands—might expect from the birds' actions and the general appearance of the whole community, to find eggs and newly-hatched chicks all about; but all are gone, and the nests now hardly to be distinguished from the surrounding heather. A few young birds there are, but they are of large size, though unable as yet—or scarcely able—to fly. It is the habit of these, when approached, to crouch and lie flat along the ground, without making any attempt to escape, even allowing themselves to be stroked and taken up in the hand. When set down again, however, they generally start off running, and often get to a great distance before they stop. Young terns and young peewits do just the same thing, and it is curious that in their manner of thus crouching, before the power of flight has been fully gained, they exactly resemble the stone-curlew, in which bird the habit is permanent, though not, I should say, very frequently indulged in after maturity has been reached. As no adult gull or peewit crouches in this way, we must suppose either that natural selection has infixed a certain habit in the young bird, suited to its flightless condition, or that in thus acting it reverts to a trick of its ancestors, which were presumably, in that case, flightless, through life. The clinging of the stone-curlew to the early habit seems to support the latter supposition, and primâ facie it is perhaps more probable that crouching in a bird should have come before flying than after it, or, at least, that it should have been resorted to by certain species, on account of their flight having become weak. It is conceivable that some birds may have alternately lost and reacquired the power of flight many times in their genealogical history. But where have the majority of the young gulls gone? That they have left the island seems evident, for, were it otherwise, they would either be all about the heather, or fill the air more numerously than do the mature birds, when they cluster above me in my walks. In the air, however, none are to be seen, though, as by far the greater number must now be full-fledged, it is there that they ought to be, with the rest. On the ground there are, as I say, a few that seem to have been later hatched, and are not yet matriculated in flight. Their proportion, however, is not more than one to a hundred of the grown gulls, whereas since every pair of these rears three young, it should be as three to two. Gilbert White speaks of that general law in accordance with which young birds are driven away by their parents, when they are no longer dependent upon the latter's attention, but can feed and look after themselves; but with social birds this law of expulsion is apt to merge in a larger one, that, namely, which is expressed in the old adage that "birds of a feather flock together." We often see this illustrated in the case of the sexes, and after watching kittiwakes at the close of the breeding-season, I can have no doubt that the same principle governs the motions of young and old birds. Of hostility on the part of the parents I have seen but little, nor is it necessary; for the young, which are now distinguished by a different coloration, both of plumage and bill, making them look like another and quite mature species, delight to associate together, so that both the rocks and the water become the scene of tolerably large gatherings of them, at which hardly an old bird is present. As the parents of these assemblies are now free from the cares of domesticity, it seems as though the reason for such a segregation must be of a psychical nature, since one can hardly suppose that the dissimilarity of plumage has anything to do with it, seeing that young and old are as familiar with one another's appearance as with their own. It is the same thing, no doubt, with the gulls on this island, but as the whole interior, or rather the crown of it, is little else than their nesting-ground, it would be difficult for the younger generation to foregather, without the constraining presence of the elder one. The inconveniences of this may be imagined. Not a remark but would be overheard, not a side-glance but would be supervised and harshly interpreted, not a giggle that would pass unreproved. In these irritating circumstances, apparently—this, at least, is my theory of it—the young people have migrated en masse, a striking proof that, with birds no less than with ourselves,

Crabbed age and youth cannot live together.

CHAPTER II

SPOILER AND SPOILED

T

TO the one smooth beach that there is here come the terns, each year, to breed, and from these, as well as from the various gulls that nest upon the island, the lesser or Arctic skua—whom some call Richardson's, as though it belonged to that gentleman—is accustomed to take toll. Sweeping the sea with the glasses, one detects, here and there upon its surface, a dusky but elegantly shaped bird, that sometimes rises from the water and descends upon it again, slowly and gracefully, but is never seen to poise and hawk at fish, like the terns themselves, or, more rarely, some of the gulls. These are those skuas who elect to take their chances at sea, and whenever a tern rises after making his plunge, with a fish in his bill, they rise also and pursue him. Then may be witnessed a long and interesting chase, in the course of which the two birds will sometimes mount up to a considerable height, rising alternately, one above the other, as though each were ascending an aerial ladder. There are no gyrations in these ascents. They are, or at least they have the appearance of being, almost perpendicular, so that they differ altogether from those of the heron and hawk, once familiar in falconry, and of which Scott has given us such a splendid description in "The Betrothed," that delightful work which an obtuse critic and publisher (l'un vaut bien l'autre very often) almost bullied its author into discontinuing. The victory is by no means always to the robber bird, and I believe that if a tern only persevere long enough it has nothing to fear, for, as in the case of the black-headed gull and the peewit, with much threatening, there is never, or, to be on the safe side, very rarely, an actual assault. It almost seems as if this logical sequence of what has gone before had dropped into desuetude, and that the skua, from having long been accustomed to succeed by the show of violence only, had become incapable of proceeding beyond the show. Why, if this were not the case, should he always leave a bird that holds out beyond a certain time? It is not that he is outstripped in the chase, for the skua's activity and powers of flight have always seemed to me to be sufficient to overtake any bird of his own size, however swift, with whom he has piratical relations. Of his own size, or something approaching to it, for I have seen him altogether baffled by the smaller turns and evasions of such a comparatively feeble flyer as the rock-pipit. But this was out of the ordinary way of his profession. The rock-pipit carried nothing, and, even if he had done, it would have been too insignificant for the skua's attention. Either amusement or murder—or the amusement of murder, which is felt by birds as well as men—must have been the object here, nor does this contravene the theory I have just laid down, since such generalised and legitimate longings are only indirectly related to the bird's special instinct.

I do not myself see how these curious relations of robber and robbed could have arisen, unless there had been, from the beginning, a marked difference in the relative powers of flight possessed by each. The skua, originally, must have caught fish, like the birds on whose angling it is now dependent, and only an easy mastery over the latter could have induced it to abandon the one way of living for the other. This superiority was probably first impressed upon the weaker species through bodily suffering, but it would have been less trouble for the stronger one could it have succeeded without coming to extremities, and this, and its constantly doing so, might in time have made it forget, as it were, the last act of the drama. But say that the skua has forgotten this, then it is likely that a certain number of the persecuted birds have by practice discovered that it has, and so emancipated themselves from the tyranny. Whether this be the reason or not, I have often noticed the persistence with which some terns refuse to yield the fish, though the nearness of the skua, and its sweeping rushes, seem quite sufficient to induce them to. Those, on the other hand, who drop it quickly, often do so whilst the enemy is still at a distance, in which case the fish falls upon the water before the skua can catch it. Upon this, the latter—if not invariably, as the fishermen assert, yet certainly in the greater number of instances—flies off without any further attempt to secure it, and I have then seen the tern sweep back, and, plunging down, retake possession of its booty. Whether, in such cases, the fish was designedly relinquished, in order to be secured again, I cannot say, but here, at any rate, we see another way in which the parasite might come to be outwitted by the more intelligent of its vaches à lait.

These competitions between skua and tern, both of them birds of such swift and graceful flight, are very interesting to watch. The skua, in the midst of the chase, will frequently sweep away, as if it had abandoned all hope, and then return in a wide circling rush, at the end of which there may be a sudden upward shoot, for the tern generally seeks to elude its pursuer by rising higher into the air. Often—and again this is just as with the peewit and gull—a pair of skuas will give chase to the same tern, and then one may see the slender, shining bird quite overshadowed by the two evil figures, as, pressing upon either side, they rise or sink towards it, often almost covering it up with their broad and dusky pinions. Twin evil geniuses they look like, seeking to corrupt a soul, or else dark shadows that this soul itself has summoned up, and that attend it, hardly now to be shaken off:

Da hab' ich viel blasse Leichen

Beschworen mit Wortesmacht.

Sie wollen, nun, nicht mehr weichen

Zurück in die alte Nacht.

For imagination can easily multiply the two into many—cares, shadows, sorrows, they are easily multiplied.

A tern that either eludes or is not molested by a skua at sea, flies home with its fish, to feed its young. But here it has often to run the gauntlet of other skuas, who wait and watch for it upon the land, sitting amidst the short stunted heather, with the brown of which their plumage, as a rule, harmonises. There are, therefore, land-robbers and sea-robbers—pirates, and highwaymen—amongst these aristocratic birds, and it would be interesting to know whether the two rôles are performed by different individuals, or indifferently by the same one. To ascertain this satisfactorily I have found a difficult matter, but I believe that here as elsewhere—in everything, as soon as one begins to watch it—a process of differentiation is going on.

Where there are terns to be robbed, the skuas—I am speaking always of the smaller and, as I have found it, the more interesting species—seem to prefer them to any other quarry, so that the gulls, generally, benefit by their presence; otherwise all are victimised, except, as I think, the great black-backed gull. The latter will, himself, attack the skua, who flies before him, so that, taking this and his size into consideration, it does not seem very likely that the parts should ever be reversed between them, nor can I recall any clear instance in which they were. Of all the birds attacked, the common gull—which, like common sense, seems to be anything but common—makes, in my experience, the stoutest resistance; for it will turn to bay and show fight, both in the air and on the water, when it has been driven down upon it. Generally it is able to hold its own, and I look upon it as a vigorous young Christian nationality, in course of establishing its independence against the intolerable yoke of Turkish oppression.

These skuas love brigandage so much that, amongst themselves, they play at it; swooping, fleeing, and pursuing, each feigns, in turn, to be spoiler or spoiled. So, at least, I understand it, for nothing ever comes of these mock skirmishings, no real fight or flight, or anything approaching to one. It is fun, frolic, with a sense of humour, maybe, as though two pirates were playfully to hoist the black flag at each other. I love the humour of it. I love the birds. Above all, I love that wild cry of theirs that rings out so beautifully "to the wild sky," to the mists and scudding clouds. By its general grace and beauty, by its sportings and piracies, its speed of flight and the rushing sweeps of its attack, this bird must ever live in the memories of those who have known it: but, most of all, it will live there by the inspiring music of its cry.

CHAPTER III

FROM DARKNESS TO LIGHT

T

TO all that I have said concerning the Arctic skua in my last chapter (I do not say it is much) I will now add what the Germans call a Beitrag, on the subject of the multitudinous variety of colouring and arrangement of markings which the plumage of this species exhibits.

Hitherto, indeed, I have spoken as if it were always of a uniformly dusky shade, but that was because I wanted that shade (and, indeed, it happened so to be) in the two that were chasing my tern. Otherwise they would not have suited the part I assigned them of twin evil geniuses, or have contrasted sufficiently with the white soul that they were seeking to corrupt. So, till that was all over, there could be no light or half-light skuas, but now that it is, and the effect produced, I permit things to be as they are.

The Arctic skua, then, is supposed by ornithologists—or, at any rate, that is how they are accustomed to speak of it—to be a bird of two different outer appearances, independent of sex, which does not add another one: dimorphic we are told it is, which means, or should mean, that it is two- or double-formed, taking form here to mean colour. Two! A hundred would be nearer the mark, I think, but I have only had the time, or the patience, to note down fifteen, which I did very carefully, through the glasses, as the birds stood amidst the short heather on the ness-side. Here they are; not, perhaps, very precisely or scientifically defined, but none the less truthfully so, for all that, and as accurate, I think, as the fact that no two people see colours quite alike will allow. But they, at any rate, bring out four facts, which, together, have, I think, a distinct meaning, viz. (1) the unmistakable and, for the most part, pronounced difference in these fifteen forms of a two-formed species; (2) the likeness of the extremely plain, permanent form to the plain-coloured great skua; (3) the same resemblance in the first true plumage of the young bird; and (4) the absence in the young bird of the two lance-like feathers which, in the old ones, project beyond the rest of the rectrices, but which are also absent in the great skua. Well, here they are.

(1) The neck, from just below the head, with the throat, breast, and ventral surface, as far as the legs, a beautiful creamy white; the rest dark, as in the ordinary dark form, but I was not careful to note the precise shade; the crown of the head—and this, it seems, is universal—sufficiently dark to appear black. This bird represents, I think, the extreme of the light or ornate form, in which dark and light are almost equally divided.

(2) The light colouring extends, speaking roughly, over the same parts, but is very much less bright and pure. It might be described as a dun-cream or cream-dun, the two shades seeming to struggle for supremacy. The cream prevails on the neck, the dun on the other parts; but even the neck is of a much duller shade than in the bird just described (No. 1). There are parts of the breast where the original sombre hue, a little softened, encroaches, cloudily, upon the lighter surface. These two birds cannot, certainly, be described as more or less handsome, merely, in the same colouring. The lighter surface, at any rate, is plainly different in shade, also its amount and distribution, though in a less degree.

(3) Another bird is much like this last one (No. 2), but there is, here, a distinct, broad, dunnish space, dividing the throat and breast parts, making, of course, a very palpable difference.

(4) Another bird—one of two standing together—is the common uniformly dark form, except that the neck and throat just below the head is, for about an inch, very much lighter, making a considerable approach to cream without quite attaining it. This light part is conspicuous in the one bird—this that I have been describing (No. 4)—but not in the other (No. 5) that it is standing by.

(5) This other one might pass for the ordinary dark form, but on examining it through the glasses a lighter, though less salient, collar is distinctly visible.

(6) In a third bird, not far off these two (Nos. 4 and 5) the whole colouring, from immediately below the crown of the head—which seems always to be black or very dark—is of a uniform brown-drab or brown-dun colour, there being not the slightest approach to a lighter collar, or any lightness elsewhere, except, as in every bird, without exception, on the quill feathers of the wings as seen in flight.

(7) In another bird the breast and ventral surface is of a delicate silvery cream, or creamy silver, something like that on the same parts of the Great Crested Grebe. On the sides of the neck, and just below the chin it is the same, perhaps a little less silvered; but between these two spaces, and so between the chin and breast, a zone of faint brown or dun, somewhat broken and cloudy, pushes itself forward from the wings, thus breaking the continuity of the light surface by the strengthening of a tendency which is, perhaps, just traceable even in the lightest specimens. Besides this, a similar clouded space is continued downwards from the back of the head, first in a diminishing quantity, and then, again, broadening out, till it joins the upper body-colour. So that here only a little of the nape is white, hardly more than what may still be described as the two sides of the neck. This is a very pretty and delicate combination.

(8) Close beside this last bird (No. 7) is a uniformly dark brown one; and

(9) Not far off, on the other side of it, one which exhibits the same sort of general effect, in a dark, smoky dun. This latter bird would generally pass as representing the dark form, and, with fluctuations in either direction, dark or light, it does represent the common form. Nevertheless, it is both light and varied compared with the extreme or uniform dark brown form beside it (No. 8), which appears to me to be the least common one of all, less so than the extreme light one (No. 1) at the other end. When I say uniform, however, I do not mean to include the crown of the head or tips of the wings, which are always darker than the rest of the plumage, nor yet that lighter shade which is on the primary quills of every individual, but only seen in flight. These exceptions must always be understood, and, moreover, the expression uniform is not to be construed with mathematical accuracy, but only as conveying the general effect upon the eye.

(10) A bird that from the dark crown of the head to the dark tips of the wings is, above and below, a uniform dark, browny dun, yet some washes lighter than the uniformly brown one (No. 8) that I have spoken of.

(11) A bird that, from the dark crown to the dark wing-tips, is, above and below, a uniform light fawny dun.

(12) A bird that would be the extreme light form (No. 1) that I have first described, were it not that, both on the throat and breast, the cream is encroached upon by cloudy barrings of a soft greyey-brown (or something between the two) which extend also over the under surface of the wings. Moreover, a toning of the darker colour of the general upper surface encroaches a little upon the cream of the nape.

(13) A bird exhibiting the uniform, dusky-dunnish colour of the common form (a shade lighter, perhaps, on the under surface), but with a cream patch on each side of the neck, just below the head. These patches are not, perhaps, of the brightest cream, but they are very conspicuous, whether the bird is seen standing or flying—in fact, the salient feature.

(14) A bird that would be the extreme light form (No. 1), but for a distinct collar of soft brown dividing the cream of the neck and throat from that of the breast.

(15) A bird that is yellowish dun on the neck and throat, mottled-brown on the breast, and a fine cream on the ventral surface.

Moreover, all these birds differed to a greater or less extent in those lighter markings of the quill feathers, both on the upper and under surface, some being lighter and some darker; following, in this respect, the general colouring. This feature, however, is only apparent when the birds fly, and I found it too laborious to include.

I can say with certainty, I think—judging by the lance-like projecting feathers of the tail, absent in the young bird, and by every other indication—that all the individuals here described by me, were birds of mature plumage. They were all established in one locality, and I was able to compare most of them with each other. I think, therefore, that though there might, perhaps, be some difference of opinion in regard to some of my colour terms—as where would there not be?—yet that the variation between the different forms is properly brought out. Without my seeking it, the list includes the two extreme forms, as I believe them to be, of dark and light; the former represented by a uniformly dark-brown bird, the latter by one having the whole under surface of the body, as well as the sides and nape of the neck, of a beautiful cream colour, by virtue of which, and of the salient contrast exhibited between this and the dusky upper surface, it is extremely handsome, not to say beautiful—one of the handsomest of all our birds in my opinion. Both the extreme forms are uncommon, but only, I think, as compared with all the intermediate shades, not with any one of them. Also the extreme light, or handsome, form seems to me to be commoner than the extreme plain one. Should not a bird like this be described as multi-morphic rather than as dimorphic? I believe that there exists as perfect a series between the two extreme forms as between the least eye-like and the most perfect eye-feather in the tail of the peacock—to take the well-known illustration given by Darwin to enforce his arguments in favour of sexual selection. The eye, however, insensibly masses the less saliently distinguished individuals together, so that those in whose plumage the light colour is more en évidence than the dark, go down as the light form, and vice versâ. Moreover, the more prononcé a bird is, in one or another direction, the more it is remarked; so that, perhaps, the intermediate shadings are forgotten, on the same principle as that by which extreme characters, in any direction, are more appreciated than less extreme ones, by the breeders of fancy birds—pigeons, poultry, etc. The uniform brown form, however, as being less striking (though extreme at one end) is not, I believe, so much noticed as those various dunnish shades, which have, in my view, been classed all together, as the dark variety.

In regard to the young birds, I only remember those nestling ones which had feathers under the fluff, as brown, without any admixture of cream. But I had not, at that time, these matters in my mind, and, moreover, I did not see many. When older, however, and able to fly, all that I have seen have had a distinct colouring of their own—for their plumage has borne a considerable resemblance to that of the Great Skua (Stercorarius catarriactes), being mottled on the back with two shades of brown, a darker and a lighter one. I got the effect of this when I watched young birds flying or standing, and one day I caught one whose wing had been injured, and saw that it was so. This resemblance is increased by such birds wanting the two lance-like feathers in the tail. As I say, this mottled brown is the only kind of colouring which I have seen in these immature but comparatively advanced birds, and my impression is that, in the still younger birds, such mottling was either absent or not so noticeable. At any rate, I have no clear recollection of it.

My own explanation of all these facts is that Stercorarius crepidatus—by my faith, 'tis a pretty name, though not wholly deserved—having been, originally, a plain homely-coloured bird, like his relative, the great skua, is being gradually modified, under the influence of sexual selection, into a most beautiful one, as represented by the extreme light or half-cream form. Natural selection, in the more general sense, seems here excluded, or, at any rate, extremely doubtful; and if it be suggested that the lighter birds have the more vigorous constitutions, that they are fuller of verve and energy, to which they owe their cream colouring, I, for my part, can only say "Prodigious!" (or think it), like Dominie Sampson. But I can assure all those who hold this unmanageable view—for really there is no dealing with it—that the one sort came not a whit nearer to knocking my cap off than did the other. But, leaving shadows, the main facts here suggest choice in a certain direction. There is a gradation of colour and pattern, connecting two forms—one plain, the other lovely. This suggests a passage from one to the other, and if the plain mature form—I mean the uniform brown one—most resembles the young bird in colouring—which to me it seems to do—whilst the young bird resembles, more than any old one, an allied plainer species, this makes it more than likely that the passage has been from the plain to the lovely, and not from the lovely to the plain. Supporting and emphasising this, we have the absence, in the tail of the young bird, of those lance-like feathers which give so marked a character to, and add so infinitely to the grace of, the old one. Of what use can this thin projection, an inch or so beyond the serviceable fan of the tail, be to the bird? Seeing how well every other bird does without it, can we suppose it to be of any service? Its beauty, however—which one misses dreadfully in the young flying bird—is apparent to any one, and it goes hand in hand with an ascending scale of beauty in colour. All this seems to me to point strongly towards sexual selection as the agency by which these changes have been, and are being, effected;[1] since I am, personally, a believer in the reality of that power, having never heard or read anything against it, so convincing to my mind as what Darwin said for it, nor seen anything that has appeared to me to be inconsistent either with his facts or his arguments.

The Bird Watcher in the Shetlands, with Some Notes on Seals—and Digressions

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