Gulls have no very salient or pronounced courting antics—I mean I have observed none—and, in the same sense, there is no special display of the plumage by one sex to the other. When amorous, they walk about closely together, stopping at intervals and standing face to face. Then, lowering their heads, they bring their bills into contact, either just touching, or drawing them once or twice across each other, or else grasping with and interlocking them like pigeons, raising then, a little, and again depressing the heads with them thus united, as do they. After this they toss up their heads into the air, and open and close their beaks once or twice in a manner almost too soft to be called a snap. Sometimes they will just drop their heads and raise them again quickly, without making much action with the bills. This is dalliance, and between each little bout of it the two will make little fidgety, more-awaiting steps, close about one another. Always, however, or almost always, one of the birds—and this one I take to be the female—is more eager, has a more soliciting manner, and tender-begging look, than the other. It is she who, as a rule, commences and draws the male bird on. She looks fondly up at him, and raising her bill to his, as though beseeching a kiss, just touches with it, in raising, the feathers of his throat—an action light, but full of endearment. And in every way she shows herself the most desirous, and, in fact, so worries and pesters the poor male gull that often, to avoid her importunities, he flies away. This may seem odd (to non-evolutionists), but I have seen other instances of it. No doubt in actual courting, before the sexes are paired, the male bird is usually the most eager, but after marriage the female often becomes the wooer. Of this, I have seen some marked instances. That of a female great plover calling up the male by her cries, when pairing took place between them, I have already given, and I have seen precisely the same thing in the case of the kestrel hawk. Female rooks, too, are often very importunate with the males in the rookery when building is going on. It is always a great satisfaction when the male and female of a species differ noticeably in their plumage, as then one is never in uncertainty as to which of them it is that performs any act. Often one must remain quite in the dark as to this, and often, again, one can only surmise. Of course, when one watches birds for any time in the breeding season, one gets clear ideas as to which is the male and which the female, but certainty is better, and certainty, at any moment or on any occasion, unless there is some marked difference between the sexes, one cannot have. In the case of gulls, however, though the plumage is alike, there is a difference in size sufficient to strike the eye, the male being larger—in the great black-backed gull, greatly larger—than the female.
Leaving the palled blandishments of its spouse, the gull husband cleaves the air, cuts the dark line of beetling precipice, and seeks the free haven of the open sea, where, with other sensible, repentant Benedicts, it wheels and circles. Suddenly a dusky form, slender and swallow-like, though as large as a pigeon, shoots over the rounded bastion of the heather, and sweeping upwards as it nears the cliffs, darts upon one of the gulls. A second pirate follows. With wild cries, and long, gliding sweeps, they press and harass the larger bird, who, doubling, twisting, avoiding, dodging, but never resisting, utters again and again a cry of distress and complaint. Its companions sweep and eddy about them, shooting athwart and between. They protest, they cry to heaven, their wild voices mingle in harsh, discordant unison with the rock-dash of the waves, and the everlasting notes of the wind. Suddenly something drops from the oppressed gull. There is a sinking towards it of one of the dark shadows—swift beyond telling, but so soft that the speed is not realised—the object is covered, lost, and almost with a jerk, the eye—or rather the brain—realises that it has been caught in the descent. Empty, and now unregarded, the robbed bird sweeps on, the pirates sweep back to the heather, the cloud of witnesses disperse themselves, and, as with us each day, each hour, things smooth themselves again over the high-placed acts of successful villainy. Who troubles over a robbed gull? What moral Nemesis concerns itself with the wrongs of some cheated, done-to-death savage or tribe of savages? Over both there is some shrieking, some eloquence at the time, but both are soon lost in oblivion, the waves close over, the world jogs on its way. Retribution, retributive justice—such fine things may exist, perhaps, but, if so, it is for showier matters. Had the skuas robbed an albatross, something, perhaps, would have happened. Their sin might have found them out—then. A gull is like an Armenian, or ... but there are so many.
Thus closes one of nature's wild dramas. The gulls are circling again now, and all is as before.
"Es pfeift der Wind, die Möven schrein
Die Wellen, die wandern und schäumen."
Such a scene as the above may often be witnessed as one lies on the heather and watches, but for one actual robbery that one sees there will be a dozen or so unsuccessful attempts at it. Yet, if one believes those who have the best opportunities of knowing, neither the great nor the Arctic skua—the latter is the bird to which attention has just been called—ever eat a fish that has not first been swallowed by a gull or tern. They say, moreover—at least, this assertion is made in regard to the great skua—that if the booty is not secured in mid-air, but falls either on the sea or land, no further attention is paid to it by the robber. For myself, I believe that the skuas always, or almost always, feed in this way, because I think that when, in the satisfaction of such a daily and almost constant want as hunger, some curious and bizarre method had been adopted it would tend to become habitual, to the exclusion of all others. Two such different plans of obtaining fish as are, respectively, swooping upon them whilst swimming in the water, and catching them in the air upon their being disgorged by another bird, after a chase which is often long and arduous, could hardly be carried on by the same bird; for it is probable that either one, to be successful, would have to be habitually employed, thus leaving no room for the other. Moreover, the adoption of such a peculiar method of obtaining food at all implies a great advantage over the older method, and this being the case it would tend entirely to supersede it. But that the Arctic skua, at any rate, thus habitually chases and robs gulls one can easily satisfy oneself, nor have I ever seen either it or the great skua stooping on fish, like terns, gulls, or gannets.
The young of the great skua are fed entirely on herrings, which are first swallowed by the parent bird, and then disgorged on to the ground in the neighbourhood of the nest. I cannot say that I have myself seen this done, for it is impossible to watch the nesting habits of a bird that always attacks you when you approach its nest, and continues to do so as long as you stay anywhere near it. In these grey desolate islands there is no sort of cover, no tree or bush with the branches of which one can make oneself a shelter, and watch unobserved. Moreover, as there is no night properly so speaking, only a portentous lurid murkiness towards midnight, which seems neither to belong to night nor day, and in which, as you can read small print, the skua can very naturally see you, there is no approaching under cloud of darkness and being there, ensconced, when morning dawns. But that the bird disgorges the herrings for the young ones after the manner of gulls generally, and does not carry them in its beak or claws, which is contrary to their practice, there can be no doubt. Now, as every one of these herrings has—as I believe it has—been secured in the manner above described, it is curious to reflect that, when finally swallowed by the young skua, it "goes a progress" for the third time, nor would it be easy, perhaps, to find another instance (outside this family of birds) of prey that has been twice given up, through fear once, and then, again, through love.
The herrings lying about the nest, and which have thus been recently disgorged for the second time, look almost as fresh and clean as if nothing peculiar had happened to them. They are disgorged whole, or nearly so; for, as I myself observed, in the great majority of cases the head is absent. Thus at one nest, in the neighbourhood of which (but this means often a considerable space of ground) forty-one herrings or their remains were lying, only ten retained the head or any part of it. At another, where there were thirteen, all were entirely headless: at another there were eight, of which one only had part of the head remaining: at another ten, eight of which were headless: at another seven, six of which were: and at another four, of which one retained the entire head. Thus, out of eighty-three herrings, only fifteen had the heads to them, though the proportion of the one to the other was different at different nests. The heads when thus absent are entirely so—that is to say, they are not to be found lying about separately. That the chick should eat the head of the herring by preference seems unlikely, and particularly when it is quite young. Yet I have seen four herrings lying about a newly-hatched chick, which were quite fresh and almost untouched, but headless. The question, therefore, arises whether the parent-bird eats the head after disgorging the whole fish, or whether, in the majority of cases, it is disgorged minus the head. Fish are, I believe, always swallowed by birds which prey upon them, head first, and would therefore, one would suppose, lie in the gullet in this direction. If disgorged again tail first, as they lay, the gills, by expanding, might offer such resistance that the head would be in most cases torn off. If this be so, then the skua may often receive the fish headless from the gull, or, if otherwise, the head would be still more likely to be torn off, on a second disgorgement. This, however, one would think, must be a very disagreeable process for the bird disgorging, and it would seem more probable that the fish can be turned or shifted in the gullet, by some muscular action on its part, so as to be brought up head foremost, as it descended; but whether there is any evidence as to this, I do not know. If the head of the herring does not remain in the gullet, then it must be eaten by the parent skuas after ejection, and it would seem that they looked upon this portion as their peculium, to which they were honestly entitled, for they seem to leave the rest, mostly, for the chicks, of which there are, commonly, two. At any rate, a number of the herrings will have only a small portion eaten off them. There is a great profusion, amounting to waste, and there does not seem any reason why the skuas should vary their diet during the breeding season, as they are asserted to do, since they have the sea always at hand, and the gulls, that are to them as their milch cows, breed in their close proximity.
In the skuas we see the habit of obtaining food by forcing another bird to disgorge what it has swallowed, perfected and become permanent, so that the birds practising it have risen—shall we say?—into rapacious parasites; but amongst the gulls themselves, who suffer by the practice, we may see, if I am not mistaken, the habit in its incipiency, and may get a hint as to how it might have arisen. When fishing-smacks are in harbour they are thronged round, sometimes, by hundreds of gulls, all the more common kinds—viz. the lesser and greater black-backed, herring-gulls, and kittiwakes—being mixed and crowded together. When some offal is thrown out, the birds that secure any are at once mobbed, and often it is torn away from them almost before they have swallowed a mouthful. To avoid this, they often rise with it in the beak and get it down as fast as they can on the wing, dodging and jerking their head from side to side amongst the pursuing crowd. But I have observed that the pursuit does not always cease after the morsel has been swallowed, and sometimes—whether rarely or frequently I am unable to say—the oppressed gull disgorges it again, in order to be left in peace. Now, amongst a crowd of birds like this, the greater number would be unable to see whether the one they were pursuing had swallowed his morsel or not, and would therefore keep pressing about him in the hope of being able to snatch at it. But, of course when birds that were hustled began to disgorge, this would be noticed and soon remembered, and they would then be hustled so that they might do so. In this, or in some similar way, I can understand the habit arising without any initial act of intelligence on the pursuing bird's part.
Perhaps, however, there would be no great unlikelihood in assuming such an act of intelligence. For one gull to conceive the idea of making another bring up what it had swallowed, might not be so very much more than for the sea-eagle to think, in regard to the osprey with the fish in his talons, "I'll make him drop it." With all the gull tribe the bringing up of the food again after swallowing it is an easy and habitual action. Not only are the young fed thus, but I have some reason to think that, during the nuptial season, the presenting in this manner of some "pretty little tiny kickshaw" by the male bird to the female is looked upon as a chivalrous and lover-like act. Perhaps such acts are reciprocal, but I will give my two little instances and let my readers draw their own conclusions. The first is the case of a herring-gull. I was watching the mother bird (as I suppose) sitting on the nest over two young ones, one of which had been hatched either only that day or the day before, and the other a day or two earlier. "At 12 o'clock a chick moves out from under the mother, and leaves the nest. It is quite active, and has the general appearance of a young chicken, being fluffy and of a yellowish grey colour, speckled with black. At 12.40 the second young one appears, pushing itself out from under the mother bird as she rises a little in the nest. At half-past one the male gull, which has been near all the while, walks slowly and importantly to the nest, which he passes and then, turning back towards it, disgorges on to the rock a small fish, which he takes up in just the tip of his bill and pushes towards both the chick on the rock and the mother on the nest, all slowly and with a dry sort of manner, as though the bird were a cynic. The mother gull leans forward from the nest and takes it, and, first, holds it on the ground, while the chick outside pecks at it. Then she swallows it herself. The male now produces in the same way a small something—I suppose a gobbet of fish—and draws the chick's attention to it by touching it with his bill and pushing it a little towards him. The chick then swallows it, upon which the male flies off and takes his accustomed stand on a large projecting point of rock close at hand." This is a conjugal, a domestic, picture. The other, which I shall now give, and in which the hero was an Arctic skua, was, perhaps, "more condoling."