# The Bird Watcher in the Shetlands/Chapter 11

CHAPTER XI
DARWINIAN EIDER-DUCKS
I HAVE seen a fair number of eider-ducks within the last few days. All the grown ones are females—not a male to be seen now—and the greater number of them are unaccompanied by ducklings. Of those that are, most have but one, and three is the maximum number that I have seen swimming together with their mother. Yet two years ago, in early June, the males here were courting the females, and when I left, about the middle of the month, but very few eggs, I believe, had been laid. This year, I learn, the birds have been very late in breeding, there having been some very "rough weather," as it is euphoniously called, in the spring—that is to say, the spring has been like a bad winter, and now the summer, though it has no very close resemblance to any of the four seasons as I have seen them elsewhere, yet comes nearest to a phenomenally bad November. I wonder, therefore, that so many of these mother eiders are without their young ones, for they should all have hatched out a brood of them not so very long ago. Why, too, should so many be swimming with one duckling only? Were these single ones of any size, one could understand the others of the brood having escaped from tutelage, but, like all I have seen, they are but little fluffy things. It looks as though their ​fellow nestlings had come to grief in some way, and if so it is probable that many entire broods have also. Yet perhaps they have merely drifted away into the wide, watery world, where they may be able enough to shift for themselves thus early. To judge by these, however, they would not have left the mother duck voluntarily—they are dutiful, dependent little things.
Where the coast is iron-bound, in delightful little bays and inlets—those sea-pools lovely to look down upon—one may watch the eiders feeding on the rocks, and try, through the glasses, to make out exactly what they are getting. In this way I am amusing myself this morning, having just run round a projecting point, towards which a family of three were advancing, and concealed myself behind a projecting ridge. Over this I can just peep at some black rocks, up which, whilst their mother waits, the little ducklings now begin to crawl. So steep is the slope that sometimes they slip and roll a little way down it, but they always recover themselves and run up it again, none the worse. In the intervals between such little mishaps they seem to be picking minute shell-fish off the rock; but what shell-fish are they? for the small white ones, with which large areas of the rock are covered, are as hard as stone, and might defy anything short of a hammer and chisel to dislodge them. It is not on these assuredly that these soft little things are feeding, and now I see that where they are most active the rock is black. There ​are broad, black bands and streaks upon it, but what these consist of, or whether they are anything more than seaweed I cannot quite make out; and here, where I lie, being above the sea's influence, there is nothing similar to instruct me. Rocks now I find—as I have often before—are inferior to foliage for concealing oneself, that is, if one wishes to see as well as to be unseen. One's head, projecting over their hard, sharp, uncompromising lines, catches the eye of a wary bird, and recesses made by their angles are not often to be found where one wants them. Twice has the mother duck been slightly suspicious, and now, to my chagrin—though it really should not be, for what can be more entertaining?—she goes to the length of calling her ducklings off the rock. This she does by uttering a deep "quorl"—a curious sound, not a quack, but something like one—on which they come scurrying down to join her, putting off to sea with the greatest precipitation, like two little boats that have only just themselves to launch—no waiting for people to get into them. I have heard this note before, and always it has been uttered as a danger-signal to the chicks. There is another one that is used on ordinary occasions, and this much more resembles a true "quack."
In spite of these various alarms, however, the young eiders are soon on the rock again, and after a while the mother walks up it, too, and begins picking and pulling with her bill over these same black surfaces. I still cannot quite make out, though now ​I surmise, what it is that gives this black, or rather indigo, tinting to the rock, and in trying to get nearer, the mother duck is again alarmed, and with another deep "quorl" or two, runs quickly down the slant, and slides into the water, close followed by her two little children. This time she swims away with them and returns no more, leaving me as disappointed as though I had thirsted for her blood.
Going down now to the rocks, where they have just been, I find that the black appearance of which I have spoken is caused by immense numbers of quite small mussels which grow thickly wedged together. It is on these that all three have been feeding, and I have no doubt that they form one of the staples of the eider-duck's food just now. Earlier in the year it seemed to be all diving, and when they brought anything up it did not look like a mussel. All about the rocks there are certain little collections of broken mussel-shells—often of a very pretty violet tint—coagulated more or less firmly together, and these must evidently have been ejected, as indigestible, by birds that had swallowed them; but whether by gulls only, or by both gulls and eider-ducks, I cannot tell. Gulls, I know, disgorge these queer kinds of pellets as well as others still more peculiar, since they occur over the interior of the island in numbers too great for any other bird to have produced them.
The eider-ducks, therefore, feed on the beds of mussels that the sea exposes at low tide, but they also, to go by appearances, devour the actual seaweed, ​irrespective of anything that may be growing upon it. Having seen them do both, I see no reason why I should reject the evidence of my eyesight in the one case more than in the other. What interests me is that I have several times during this week seen the same duck, with her young ones, feeding along this one flat part of the coast-line, where it forms a beach, whereas all the others that I have seen have kept in the neighbourhood of the rocks. Even about the shores of this small island it seems as though a process of differentiation were going on, and that whilst the great majority of the eider-ducks affect a diet of shell-fish, and, therefore, haunt the broken, rocky parts where it is to be best obtained, some few prefer the seaweed growing on the smooth, shallow bottoms, which they therefore do not leave, or, at least, more frequently resort to.
A difference of food like this, involving a residence in different localities, must lead to change in other habits, to which structure would, in time, respond, so that, at last, upon Darwinian principles, two different birds would be produced. Thus anywhere and everywhere one may see with one's own eyes—or think that one sees, which is just as instructive—the early unregarded stages of some important evolutionary process.
It is a good thing, I think, thus to exercise one's imagination, and by observing this or that more or less slight deviation from the main stream of an animal's habits, to try and picture its remote future descendants. ​Too little, I think, has been done in this way. The imaginative element is one without which all things starve. In natural history it is particularly wanted, and would have particularly good effects. Most naturalists think only of what is the rule in any animal's habits—exceptions they do not care about—yet, looked at in a certain way, they are still more interesting. Moreover, there is a great tendency to see an animal do just what it is supposed to do, and this tendency does not conduce to keen and interested observation. But the future modification of any species must depend largely upon deviations, on the part of individuals belonging to it, from its more ordinary line of conduct, so that any man who should wish rationally to speculate on this future must become, perforce, a patient noticer of such deviations, and, therefore, a great observer of the animal in question.
To support a theory is a great motive towards the collection of facts, yet a number of small-minded people are always deprecating what they call "mere theory" in field natural history, and crying out for facts only. Theory, however, is a soil in which facts grow, and there is a greater crop from a false one than from none at all. The history of astrology and alchemy are instances of this—if, indeed, the latter, in its fundamental belief, does not turn out to have been true after all. When have men been much interested in facts—apart from mere gaping wonder or amusement—except in connection with ​some idea in their mind, which, by giving, or seeming to give, them significance, as it were irradiated them? The "matter-of-fact man," as that lowest type of one is called, is interested in comparatively few facts even, and such fancy and imagination as he does possess plays around those few.
To return to the eider-ducks, I cannot, of course, be quite certain that it is always the same family party that I see along the beach by the fringe of seaweed, but I have little doubt that it is; for, in the first place, it always consists of the mother and three ducklings, and in the next, there is never another bird or party of birds there at the same time with them. The double coincidence is, I think, decisive, for most of the eiders that have ducklings at all, have either one only or two, whilst the greater number are without any. But then, to be sure, I have only been here a week, nor have I given the matter any very special attention. It is not quite constaté, only I like to think things, and then think as though they were as I think.