_ LECTURE III. THE DABCHICKS: III. TREPIDA STAGNARUM. LITTLE GREBE
100. The two birds--Torrent-ouzel, and Lily-ouzel,--which we have been just describing, agree, you will observe, in delicate and singular use of their feet in the water; the torrent-ouzel holding itself mysteriously at the bottom; and the lily-ouzel, less mysteriously, but as skillfully, on the top (for I forgot to note, respecting this raft-walking, that the bird, however light, must be always careful not to tread on the edges of leaves, but in the middle, or, rather, as nearly as may be where they are set on the stalk; it would go in at once if it trod on the edges). But both the birds have the foot which is really characteristic of land, not water-birds; and especially of those land species that run well. Of the real action of the toes, either in running, or hopping, nothing is told us by the anatomists--(compare lecture on Robin, Sec. 26); but I hope before long to get at some of the facts respecting the greater flexibility of the gripping and climbing feet, and elasticity of running ones; and to draw up something like a properly graduated scale of the length of the toes in proportion to that of the body.
[Illustration: FIG. 12.]
And, for one question, relative to this--the balance of a bird _standing_, not gripping--is to be thought of. Taking a typical profile of bird-form in its abstract, with beak, belly, and foot, horizontal (Fig. 12), the security of the standing, (supposing atomic weight equal through the bird's body, and the _will_, in the ankle, of iron,) is the same as of an inverted cone, between the dotted lines from the extremities of the foot to those of the body; and, of course, with a little grip of the foot or hind claw, the bird can be safe in almost any position it likes. Nevertheless, when the feet are as small in proportion as the Torrent-ouzel's, I greatly doubt the possibility of such a balance as Bewick has given it (Fig. 13 _a_). Gould's of the black-bodiced Ouzel (Fig. 13 _b_) is, I imagine, right. Bewick was infallible in plume texture, and expression either of the features of animals, or of any action that had meaning in it; but he was singularly careless of indifferent points in geometry or perspective; and even loses character in his water-birds, by making them always swim on the top of the water.
[Illustration: FIG. 13_a_.]
101. But, whatever their balance of body, or use of foot, the two birds just examined are, as I said, essentially connected with the running land birds, or broadly, the Plovers; and with the Sand-runners, or (from their cry) Sandpipers, which Mr. Gould evidently associates mentally with the Plovers, in his description of the plumage of the Dunlin; while he gives to them in his plates of that bird--the little Stint, and common Sandpiper--most subtle action with their fine feet,--thread-fine, almost, in the toes; requiring us, it seems to me, to consider them as entirely land-birds, however fond of the wave margins. But the next real water-ouzel we come to, belongs to a group with feet like little horse-chestnut leaves; each toe having its separate lobes of web. Why separated, I cannot yet make out, but the bird swims, or even dives, on occasion, with dexterity and force. These lobe-footed birds consist first of the Grebes, which are connected with fresh-water ducks; and, secondly, of the Phalaropes, which are a sort of sea-gulls. No bird which is not properly web-footed has any business to think itself either true duck or true gull; but as, both in size and habit of life, the larger grebes and phalaropes are entirely aquatic and marine, I shall take out of them into my class of dabchicks, only those which are literally dabblers in habit, and chickens in size. And of the Grebes, therefore, only the one commonly known as the Dabchick, the 'Little Grebe,' 'Colymbus Minutus' (Minute Diver), of Linnaeus. A summary word or two, first, respecting the Grebe family, will be useful.
[Illustration: FIG. 13_b_.]
102. Grebe, properly, I suppose, Grebe, from the French, is not in Johnson, nor do any of my books tell me what it means. I retain it, however, as being short, not ugly, and well established in two languages. We may think of it as formed from gre, and meaning 'a nice bird.' The specialities of the whole class, easily remembered, are, first, that they have chestnut-leaf feet; secondly, that their legs are serrated behind with a double row of notches--(why?); thirdly, that they have no tails; fourthly, that they have, most of them, very fine and very comic crests, tufts, tippets, and other variously applied appendages to their heads and chins, so that some are called 'crested,' some 'eared,' some 'tippeted,' and so on; but the least of them, our proper Dabchick, displays no absurdity of this sort, and I have the less scruple in distinguishing it from others. I find, further, in Stanley's classes, the Grebes placed among the short-winged birds, and made to include all the divers; but he does not say how short their wings are; and his grouping them with guillemots and puffins is entirely absurd, all their ways and looks, and abodes, being those of ducks. We can say no more of them as a family, accordingly, until we know what a duck is;--and I go on to the little pet of them, whose ways are more entirely its own.
103. Strangely, the most interesting fact (if _fact_ it be) that it builds a floating nest, gains scarcely more than chance notice from its historians. Here is Mr. Gould's account of it: "The materials composing this raft or nest are weeds and aquatic plants carefully heaped together in a rounded form; it is very large at the base, and is so constantly added to, that a considerable portion of it becomes submerged; at the same time it is sufficiently buoyant to admit of its saucer-like hollow top being always above the surface. In this wet depression five or six eggs are laid. The bird, always most alert, is still more so now, and scarcely ever admits of a near examination of the nest-making, or of a view of the eggs. In favorable situations, however, and with the aid of a telescope, the process may be watched; and it is not a little interesting to notice with what remarkable quickness the dabchick scratches the weeds over her eggs with her feet, when she perceives herself observed, so as not to lead even to the suspicion that any were deposited on the ill-shapen floating mass. This work of an instant displays as much skill in deception as can well be imagined."
104. It is still left to question, first, what is meant by a wet depression?--does the bird actually sit in the water, and are the eggs under it? and, if not, how is the water kept out? Secondly, is the floating nest anchored, and how? Looking to other ornithologists for solution of these particulars, I find nobody else say anything about a floating nest at all. Bewick describes it as being of a large size, and composed of a very great quantity of grass and water plants, at least a foot in thickness, and so placed in the water that the female hatches her eggs amidst the continual wet in which they were first laid. Yarrell says only that it is a large flat nest made of aquatic plants; while Morris finally complicates the whole business by telling us that the nest is placed often as much as twenty or thirty yards from the water, that it is composed of short pieces of roots, reeds, rushes, and flags, and that when dry the whole naturally becomes very brittle.[23]
[23] I hear, from a friend in whose statements I have absolute confidence, that he has found the eggs of the water-hen laid on a dead sycamore leaf by the side of a shallow stream, one of the many brooks near Uxbridge. 105. While, out of my fifteen volumes of ornithology, I can obtain only this very vague account of the prettiest bird, next to the kingfisher, that haunts our English rivers, I have no doubt the most precise and accurate accounts are obtainable of the shapes of her bones and the sinuosities of her larynx; but about these I am low-minded enough not to feel the slightest curiosity. I return to Mr. Gould, therefore, to gather some pleasanter particulars; first, namely, that she has a winter and summer dress,--in winter olive gray and white, but in summer, (changing at marriage time) deep olive black, with dark chestnut chemisette. Infant dabchicks have "delicate rose-colored bills, harlequin-like markings, and rosy-white aprons." The harlequin-like markings I should call, rather, agate-like, especially on the head, where they are black and white, like an onyx. The bodies look more like a little walnut-shell, or nutmeg with wings to it, or things that are to be wings, some day.
106. Even when full-grown, the birds never fly much,--never more, says Morris, "than six or ten feet above the water, and for the most part trailing their legs in it; but either on the water or under it, every movement is characterized by the most consummate dexterity, and facile agility. The most expert waterman that sculls his skiff on the Thames or Isis, is but an humble and unskillful imitator of the dabchick. In moving straightforward (under water?), the wings are used to aid its progress, as if in the air, and in turning it has an easy gliding motion, feet and wings being used, as occasion requires, sometimes on one side and sometimes on the other. It walks but indifferently, as may readily be imagined from the position of the legs, so very far back. It is pleasant to watch the parent bird feeding her young: down she dives with a quick turn, and presently rises again with, five times out of six, a minnow, or other little fish, glittering like silver in her bill. The young rush towards the spot where the mother has come up, but she does not drop the fish into the water for them to receive until she has well shaken it about and killed it, so that it may not escape, when for the last time in its own element. I have seen a young one which had just seized, out of its turn I have no doubt, the captured prey, chased away by her, and pursued in apparent anger, as if for punishment, the following one being willingly given the next fish without any demur."
107. Mr. Gould seems to think that the dabchick likes insects and fish spawn better than fish, or at least more prudently dines upon them. "That fish are taken we have positive evidence from examples having been repeatedly picked up dead by the fishermen of the Thames, with a bull-head or miller's thumb in their throats, and by which they had evidently been choked in the act of swallowing them. That it is especially fond of insects is shown by the great activity it displays, when in captivity, in capturing house-flies and other diptera. Those who have visited Paris will probably have seen the grebes in the window of the restaurateur in the Rue de Rivoli. For years have a pair of these birds been living, apparently in the greatest enjoyment, within the glass window, attracting the admiration of all the passers-by. The extreme agility with which they sailed round their little prison, or scrambled over the half-submerged piece of rock for a fly, was very remarkable. That no bird can be more easily kept in a state of confinement is certain."
108. This question about its food is closely connected with that of its diving. So far as I understand Mr. Morris, it dives only when disturbed, and to escape,--remaining under water, however, if need be, an almost incredible time, and swimming underneath it to great distances. Here we have, if we would only think of it, the same question as that about the water-ouzel, how it _keeps down_; and we must now note a few general points about diving birds altogether.
It is easy to understand how the properly so-called divers can plunge with impetus to great depths, or keep themselves at the bottom by continued strokes of the webbed feet; but neither how the ouzel walks at the bottom, if it be specifically lighter than the water, nor how a bird can swim horizontally under the surface; at least it is not enough explained that the action must be always that of oblique diving, the bird regulating the stroke according to the upward pressure of the water at different depths.
109. But there are many other points needing elucidation. It is said (and beautifully insisted on, by Michelet,) that great spaces in the bones of birds that pass most of their lives in flight are filled with air: presumably the bones of the divers are made comparatively solid, or it is even conceivable--if conceptions or suppositions were of any use,--that the deep divers may take in water, to help themselves to sink. The enormous depths at which they have been caught, according to report, cannot be reached by any mere effort of strength, if the body remained as buoyant as it evidently is on the surface. The strength of the wing must, however, be enormous, for the great northern diver is described as swimming under water "as it were with the velocity of an arrow in the air" (Yarrell, vol. iii., page 431); or to keep to more measured fact, Sir William Jardine says, "I have pursued this bird in a Newhaven fishing-boat with four sturdy rowers, and notwithstanding it was kept almost constantly under water by firing as soon as it appeared, the boat could not succeed in making one yard upon it" (_ibid._, p. 432).
110. But this is followed by the amazing statement of Mr. Robert Dunn, p. 433, that in the act of diving it does not appear to make the least exertion, but sinks gradually under the surface, without throwing itself forward, the head being the last part that disappears. I am not fond of the word 'impossible,' but I think I am safe in saying that according to the laws of nature no buoyant body can sink merely by an act of volition; and that it must pull itself down by some hitherto unconceived action of the feet, which in this bird are immensely broad and strong, and so flat that it cannot walk with them, any more than we could with two flat boards a yard square tied to our feet; but, when it is caught on land, shoves its body along upon the ground, like a seal, by jerks. All these diving motions are executed in a more delicate but quite as wonderful way by the dabchick,--more wonderful indeed it may be said, because it has only the divided or chestnut-leaf-like foot, to strike with. We shall understand it perhaps a little better after tracing, in a future talk, the history of its relations among the smaller sea-gulls; meantime, in quitting the little dainty creature, I must plead for a daintier Latin name than it has now--'Podiceps.' No one seems to have the least idea what that means; and 'Colymbus,' diver, must be kept for the great Northern Diver and his deep-sea relatives, far removed from our little living ripple-line of the pools. I can't think of any one pretty enough; but for the present 'Trepida' may serve; and perhaps be applied, not improperly, to all the Grebes, with reference to their subtle and instant escape from any sudden danger. (See Stanley, p. 419.) "It requires all the address of a keen sportsman to get within shot," and when he does, the bird may still be too shrewd for him. "I fired at the distance of thirty yards; my gun went quick as lightning, but the grebe went quicker, and scrambling over, out of sight, came up again in a few seconds perfectly unhurt."
I think, therefore, that unless I receive some better suggestion, 'Trepida Stagnarum' may be the sufficiently intelligible Latin renaming of our easily startled favorite. _