I should be pretty sure, therefore, that he swims only and does not fly (if this expression is permissible) under water, if I did not seem to remember having once seen him do so, as I lay with my head just over the river's bank and he passed underneath me. But it was years ago; I have no note, and my memory may very likely have deceived me. Possibly both in regard to this, as well as the way in which he dives, the dabchick may be in a transition state. His multifariousness in this latter respect seems to render this likely. The shag, if I mistake not, never dives in any other way than that which I have described, unless he is really alarmed, when he disappears instantaneously and in a dishevelled manner.
The moor-hen, also, may follow no fixed plan in his diving, for I have certainly seen him using his feet only under water, and I believe I have also seen him using his wings. Though this, too, was many years ago I ought not to be mistaken, as the incident made such a deep impression on me at the time. I was standing on the bank of a little creek, or streamlet, running out of a reedy moor-hen-haunted river. The creek itself, however, was clear where I stood, and all at once a strange object passed right in front of me, swimming beneath the surface. It was a moor-hen, but the wings used in the way I have been discussing—a thing to me quite unexpected—seemed to give it an entirely unbirdlike appearance, and surprised me into thinking for the moment that it was some kind of turtle. The legs, I believe, were also used, alternately in a kind of long, gliding stride, and may just have touched the mud at the bottom. This, however—and I believe the moor-hen often walks in this way along the bottom rather than swims—would seem to make its use of the wings at the same time all the more unlikely. I have but my memory, which, as evidence after so many years, is of little value. In all such matters what is wanted is a note taken down at the time. As to the actual dive down of the moor-hen, whenever I have seen it it has always been a sudden duck, sometimes in a rather splashy and disordered manner, but whether the wings were ever thrown partly open I am not able to say. I have noted cases, however, where they certainly were not, and this again makes it more likely that the moor-hen in diving does not use the wings at all. I do not know that I have ever seen the moor-hen dive, unless it was in alarm from having seen me; and with regard to this a question arises which, I think, is of interest—to what extent, namely, does diving enter into the moor-hen's ordinary habits, how often does it do so of its own free will? Possibly it may differ as to this in different localities. Jefferies, for instance, writes as though it were always diving. Yet I have watched moor-hens latterly, at all seasons, and for several hours at a time, without having once seen them do so; so that from seeing them thus au naturel, and without any suspicion of my proximity, I might have come to the conclusion that they were not diving birds at all. As it is, I am inclined to think that they rarely dive except to avoid danger, and only then when surprised and as a last resource. For instance, if a moor-hen sees one from the smallest distance it flies to the nearest belt of reeds, but if one appears quite suddenly on the bank just above it—as sometimes happens—it will then often dive. Even here, however, according to my own experience, it is more likely to trust to its wings; so that, as it seems to me, the habit under any circumstances is only an occasional one, and may, therefore, be in process either of formation or cessation. If we look at the moor-hen's foot, which shows no special adaptation to swimming, but a very marked one for walking over a network of water-herbage, the former of these two suppositions seems the more probable. The bird from a shore and weed-walker has become aquatic, and is probably becoming more so. If the habit of diving is only becoming established, it is possible that some localities might be more conducive to its quick increase than others, and it would be interesting, I think, if observers in different parts of the country would make and record observations on this point.
The chariness of the moor-hen in diving is the more interesting because the coot, which belongs to the same family, has the same general habits, and has evidently become aquatic by the same gradual process, dives frequently, and is accustomed to feed upon weeds which it pulls up from the bottom of the water. Here is an instance, in which it will also be seen that the coot's manner of diving is very much more formed than the moor-hen's, which may be said to be archaic. "It dives down and reappears, shortly, with some dank weediness in its bill, which it proceeds to peck about and swallow on the surface. Then it dives again, comes up with some more, which it likewise eats, and does this several times in succession. After five or six dives it comes up with quite a large quantity, with which it swims a little way to some footing of flag and reed, and on this frail brown raft it stands whilst picking to pieces and eating 'the fat weed' which it has there deposited. Having finished, or selected from it, it swims to the same place again and continues thus to dive and feed, each time coming up with some weeds in its beak, which I see it eat quite plainly. It is charming to see this, and also the way in which the bird dives, which is elaborate, studied, and yet full of ease. Rising, first, from the water in a light, buoyant manner as if about to ascend, balloon-like, into the air, it changes its mind in the instant and plunges beneath the surface, having, as it goes down, a very globular and air-bally appearance. It is like the sometime dive of the dabchick, but with more deportment and less specific gravity. The dabchick is an oiled powder-puff, the coot a balloon, the dabchick a small fluff-ball, the coot an air-ball."
From this it would seem as though the coot belonged to the cormorant school of diving, disagreeing in this with the moor-hen, to whom it is so closely allied, whilst agreeing with the dabchick, as well as the great crested grebe and other birds—the cormorant itself—with whom it has no close affinities. But this cannot be said without considerable qualification, for, though the description I have given is from the life and seen over and over again, yet at other times the dive down of this bird is so totally different that no one who had seen only the one could think it capable of the other. In the winter, coots swim about in flocks, and then one may see first one little spray of water thrown up as a bird disappears, and then another. That is all; there is the spray and there is no bird, whereas just before there was one. Indeed, I think it is a quicker dive than any that I have seen a sea-bird make, only equalled, perhaps (or even, perhaps, not quite equalled), by that of a really alarmed dabchick. As for the process of it, it is undiscoverable, the eye catches only the spray-jet, which is pretty and always just the same. But there is no disorder, no higgledy-piggledyness. It is something which you can't see, but which you feel is the act of a master. Here again, then, the coot in diving is quite the moor-hen's superior. The dive of the latter bird is, as we have said, archaic. It is unpolished, and greatly wants form and style. Now, the coot is fin-footed—that is to say, the skin of the toes is extended so as to form on the interspace of each joint a thin lobe-shaped membrane. In this formation, which likewise distinguishes the grebes, we may, perhaps, see the gradual steps by which the feet of some more purely aquatic birds have become webbed. As the lobes became larger they would have met and overlapped, and from this to an actual fusion does not seem an impassable gulf. This, however, is only a supposition. It seems more likely that the web has been, in most cases, gained by the extension of the slight membrane between the toes, at their junction with one another. Possibly the lobes on the toes of the coot were gained before he became a swimmer, and served the purpose of supporting him on mud or floating vegetation, or, as perhaps is more probable, they may have been developed in accordance with the double requirement. At any rate, if we suppose this structural modification to have been effected after the bird became in some degree truly aquatic, then, though this does not prove that the period at which it became so was longer ago than in the case of the moor-hen, which has remained structurally unaffected, yet it, perhaps, renders it likely, and we can, by supposing so, understand why the one bird should dive habitually and the other only occasionally.
The great crested grebe exhibits the same feature of variety in his manner of diving as does his sprightly little relative the dabchick. Sometimes it is quite informal—he just spears the water before disappearing, sinking in it a little before he spears—but at others there is the cormorant leap upwards as well as forwards, before going down. Of course, no more than with the dabchick is there the same tremendous vigour, the wonderful supple virility which lives in the leap of this strong-souled sea robber. I say "of course," for anyone who has watched these birds—the most ornamental, perhaps, of any except swans that swim the water—must have remarked a quiet, easy, one may almost say languid, grace—something suggestive of high birth, of "Lady Clara Vere de Vere"-ness—in their every, or almost every, action. Masters of grace indeed they are, and consummate masters of diving. I do them wrong descanting upon them here so scantily, but space, my constant and persistent enemy, will have it so. I have not even sufficient to make them any further apology.
