The Zoologist/4th series, vol 3 (1899)/Issue 699/An Observational Diary of the Habits of Nightjars, Selous

by Edmund Selous

 

AN OBSERVATIONAL DIARY OF THE HABITS
OF NIGHTJARS (CAPRIMULGUS EUROPÆUS),
MOSTLY OF A SITTING PAIR. NOTES TAKEN
AT TIME AND ON SPOT.

By Edmund Selous.

 

June 22nd, 1898.—Crawled up behind a small elder bush some three paces from where a Nightjar had laid her eggs. When nearly there the bird flew down, not on to nest, but close to it. Shortly afterwards the other bird flew down beside it, and immediately I heard a very low and subdued "churr," expressive of quiet contentment, I think, and very different from the ordinary loud note of the bird. After I had got up under cover of the bush the following occurred:—One of the birds came on to the eggs, and began to "churr" softly. The other bird then flew down and sat close beside it, also churring (I think, but cannot be certain if both churred together). The bird last arrived then flew away, leaving the other on the eggs. This one, after ten minutes or so, also flew away, uttering the "quaw-ee" note. In a little while one of the birds returned, and settled near the eggs. Its mate very shortly joined it; and I now heard another note, a low croon, quite distinct from the "churr" uttered by one or both of them. One bird then flew away, and the other came and sat on the eggs, and began to "churr" softly at first, then loudly, the ordinary churring note. In some ten or fifteen minutes' time it flew off. In a little while one of the birds returned, and was followed almost at once by the other. Both flew down near the eggs, and soon one settled itself on to them, the other flying away. I had now got my watch out, and this bird sat for fifty-five minutes silently (no "churr," no sound at all), at the end of which time its partner flew near by clapping its wings, and then sat on a bush close behind me (as I judged, for I could not turn), and "quaw-eed."^[1] Upon this, as in answer to a summons, the sitting bird left the eggs, uttering the same note, and both flew away together. They were away for nearly twenty minutes, when one of them returned (this time flying right down on to the eggs in silence), and continued to sit silently for an hour or the best part of an hour (it being now too dark to see the time), during all which time I was digging out the sand behind the bush so as to have a better place to sit and watch in. I then went out and brought some branches to make more cover, but in placing these I startled the bird away. Having made a good shelter I left. I imagine that the bird which sat twice for a short time only and churred on the eggs whilst alone was the male, whilst the silent and long-sitting bird was the female.

June 23rd.—Found bird sitting at 3.15 p.m. The Nightjar seems almost as good an example of protective colouring as any insect. It harmonizes to absolute perfection with the sandy ground, dry sticks, and pieces of fir-tree bark, amongst which it so often lays its eggs. My shelter was at some three paces of the bird as it sat, and I could distinctly see the outline of the latter part of its body, and one wing with the tail. Yet, scrutinizing it with the utmost attention for ten minutes or a quarter of an hour at a time, it was only at twenty minutes past four that I finally became convinced it was the bird and not a piece of fir-bark at which I was looking; and this though I knew the eggs to be there, yet could not see them. Stayed till five, during all which time the bird sat in silence.

Returned at 6.10 p.m., and found bird (presumably the same one)^[2] still sitting in the same position.

6.25.—A. bird in clump of fir-trees near churred slightly.

8.15.—First flying note of the Nightjar heard as well as the "churr."

8.40.—Sitting bird relieved by her mate. He settled down facing her, and then, as it were, snoozled up to her, churring softly. Whilst doing so he waggled his tail from side to side, as did the other one also in exactly the same way. I believe therefore that both birds churred together, though I could not be quite certain that I heard the two separate notes. The bird I had been watching then flew away with a "quaw-ee," the other one having insinuated itself into her place on the eggs, but with the head turned the other way (to where the tail of the other bird had been). In a minute or two only the first bird returned, when both immediately flew away together (at 8.40) quaw-eeing. I could then see the eggs plainly. They had not till then been uncovered, one bird having, as it were, squeezed itself on and the other off them. (My tame Doves used to act in the same way, the one snoozling itself up to the other, and thus taking its place.)

8.55.—One bird certainly (I think two) flew near, clapping their wings loudly and repeatedly. I took them to be the pair.

8.55.—Two birds (probably the pair) flying about near, clapping their wings and quaw-eeing.

9 (nearly).—Bird flew down direct on to eggs and sat on them (in the accustomed position) for a second on two only, then again flew off quaw-eeing.

9.5.—A bird settled down somewhere not very far from the eggs, and kept churring. Another bird flew by quaw-eeing.

9.25.—A bird flew silently down near the eggs, then rose, hovered a few seconds over the tops of the nettles, thistles, &c, and again went down near them. It then again rose, and hovered over the eggs with its wings aloft over its back (characteristic), and once more flew down a little way off. Finally, at 9.27 or 9.28, it rose and came down on to the eggs with a clattering noise, made no doubt with the wings. It took some time to settle itself comfortably on to the eggs (which it did in the accustomed position), and then sat silently, not churring.

9.35.—A bird (the mate, I make no doubt) flew quite near (settled once, I think), clapping its wings and "quaw-eeing." From the sound I thought it clapped its wings whilst settled on the ground, as well as whilst flying, but cannot be sure either of this or that it did settle. During this time, and till 9.45, when I went away, the sitting bird was quite silent.

June 24th.—At 8.10 p.m. found bird sitting, but in a different position, the head being turned the other way. It was a wet night, and came on to rain a little worse as I arrived. At 8.25 an Owl flew by (flying fast and high) in exactly the same direction, and about the same time (for I had not looked at my watch) as the night before.

8.28.—Churring commences.

8.33.—A Nightjar flew by, uttering a single note like "queek queek," not the more usual "quaw-ee."

8.42.—Sitting bird relieved. The arriving bird hovered for some time above its mate, waving its wings rapidly, but uttering no sound. Whilst it was acting thus the sitting bird churred quietly and contentedly, wagging its tail from side to side as before. The whole body waggles as well as the tail, but the tail is the most noticeable. In a second or two the hovering bird settled on the ground beside the other, which then flew off quaw-eeing. Its partner continued to sit where it was—not on the eggs, but close by them—for two or three seconds, when it also flew off.

8.49.—Two birds (probably the pair) flew by pursuing each other, one of them clapping its wings loudly and repeatedly. The birds being now gone, I went round the bush, and picked some of the nettles and grasses from about the eggs so as to have a better view of them from my shelter; then went back.

8.55.—Two birds flew near quaw-eeing and clapping their wings, and one settled not very far off—in a small fir tree, I think—and churred. After a little it rose, clapping its wings. At this time some other Nightjar, after churring, uttered a note like "chu-oo chu-oo chu-oo," quite different from the usual "quaw-ee" as the bird takes flight. Whether this note is uttered whilst the bird is still sitting, or only as it flies off, I do not yet know.^[3]

No bird returned to the eggs for over an hour, and I grew more and more uneasy. At last, at 10 o'clock, one returned, and hovered for some time above them. Instead of settling on them, however, it made a dart off to one side, and came down on the ground a little way off. Shortly afterwards it flew away. At 10.30 the eggs were still uncovered, though one of the birds had again hovered in the neighbourhood, though not very near them. I now went away. The eggs had therefore been uncovered from 8.42 to 10.30 as a minimum.

June 25th (10.15 a.m.).—Found bird sitting in the accustomed position (head towards me, that is, and tail overlapping dried stalk). Could see it even better than before, owing to having removed what thin and scattered herbage had become interposed. It sat quite motionless, the large eye shut, but occasionally opening to a very limited extent so as to show a long black slit.

10.30.—The low sleepy "churr" of a Nightjar from neighbouring fir-clump. Left a little after 10.30.

At about 11 a.m. crept up behind a bush, near which sat another Nightjar with young birds (I had disturbed this family three or four days before, when the old bird spun along the ground as if hurt), From here I could see the bird sitting just as the other one did on her eggs with a young one on each side of her. This I did not remark till one of the young birds moved and then shuffled itself more under its mother's breast, causing her to sit with the head held higher. I then saw both this and the other young one for the first time. Just then (11.25) the old bird either saw me or suspected my presence, and went off the nest, spinning over the ground in various directions. She then flew to a small bush near by, and sat there, uttering a note like "chook chook chook." Shortly after she flew off and out of sight.

11.30.—Bird returned to a bush close to the one she had left, and again uttered the note "chook chook"; then sat silent.

11.55.—Bird left the bush and flew around evidently disquieted. At 12 I came out, but before leaving walked to where the young birds had been, and where I had seen them after the mother had flown away. To my surprise they were gone, and, though I looked carefully all about, I could not find them anywhere. The "chook chook chook" therefore of the mother may have been the danger signal.

12.30.—Came back to the first bird, and found it (assuming it was the same) still sitting, but in a changed position, the head being now turned the other way. This time I was entirely deceived by the bird's resemblance to an inanimate object (though the bird I had just left had not deceived me). Not catching the outline of the tip of the wings and tail across the dry stalk (to which I had become accustomed) my eye rested full upon it, and I thought I was looking at a piece of fir-bark, one of those amongst which it sat. I, in fact, looked for the eggs upon the bird, for I knew the exact spot where they should be. But as I should have seen them at once, owing to their light colour, I felt sure that they must be covered, and, gazing still more attentively, all at once, by an optical delusion as it seemed, rather than by the passing away of one, the piece of fir-bark became the bird. The broad flat head, from which the short beak hardly projects noticeably, presents no special outline for the eye to seize on, but is all in one line with the body. It looks just like the blunt rounded end of a stump or piece of fir-bark, whilst the dark brown lines and mottlings of the feathers not only blend with and fade into the surroundings, but have in themselves, at a little distance, a great resemblance to the flaked surface of the bark, the lighter feathers exactly mimicking those patches where some of the layers have been more newly flaked off. This would only be of special advantage to the bird when, as in the present instance, it had laid its eggs amidst pieces of fir-bark, and, did it invariably do so, a special protective resemblance might perhaps be admitted. This, however, is not the case. It lays them also under beeches or elsewhere where no fir-bark is to be found. Unless therefore it could be shown that a large majority of Nightjars lay their eggs in the neighbourhood of fir-trees, the theory of a special resemblance due to the action of natural selection must be given up, as I believe it ought to be in other apparent instances. No doubt when the objects adjacent are different the sitting bird may often appear to have a special resemblance to one or other of them; but as, owing to its habits, such objects would be mostly of the same general description, the bird's colouring may have been made generally protective in relation to its incubatory habits. The Nightjar lays on the ground, and one of the birds sits on the eggs without leaving them the entire day. Day, however, is night to the Nightjar, which not only sits on its eggs, but sleeps, or a least dozes, on them as well. It is therefore much exposed during this period, and would be liable to be taken unawares without some protection, and such protection it has by virtue of its plumage and its habit of sitting very close. Drowziness may in this case have meant security both to bird and eggs, for the most sleepy birds would, by keeping still, least endanger their young at all stages.

The two birds that I am watching have laid their eggs in the midst of pieces of fir-bark of various sizes lying on a sandy soil, from which spring nettles, thistles, &c, with alder bushes scattered about singly or in clumps.

Left at 1.30, the bird not having moved perceptibly.^[4] During most of the time the eyes were closed.

June 25th.—Found bird sitting at 8.15 p.m. Position a little varied from the usual one. The eye shut, the bird seeming to be asleep or dozing.

8.21.—A bird churred sleepily, but soon ceased.

8.30.—The first prolonged churring. I shall refer^[5] to the occasional modification of the "churr" when it becomes less instrumental, and more voice, as it were, enters into it (for the ordinary "churr" sounds more instrumental than vocal). I shall also allude to the "chu-oo chu-oo chu-oo" uttered just after the "churr." But besides these the "churr" (as heard by me at this moment) sometimes ends in a sort of jubilee of gurgly notes impossible to describe.

8.35.—First bird seen flying slowly and clapping its wings in a very leisurely manner. Upon the sound of a gun fired near the noisy "churr" sinks into a low bubbling note.

8.37.—The Owl flies high in the air in same direction as night before.

8.49.—Sitting bird relieved. Her mate came, I think, from neighbouring plantation, uttering the "quaw-ee" note, which she acknowledged with a soft churring. The newly-come bird then seated itself beside the other in exactly the same attitude (like a Swift on the ground) at a distance of about six inches, and both birds churred together,^[6] wagging (it is the best word) their whole bodies, as well as their tails, from side to side, especially the one on the eggs. In a second or so this latter rose from the eggs, and flew away to the plantation from which the other had come. This one did not move on to the eggs, but continued to sit where it was, and in a few seconds (before I had finished making the note) flew off after the other.

A little before nine a bird passed near quaw-eeing. Another flew by a little after, also quaw-eeing, and clapping its wings in a rather peculiar manner. No doubt they were the pair. At a few minutes past nine one of the birds came back, hovered a little over the eggs, then darted to one side, and settled on the ground a little way from them. Soon it walked up to them (or rather waddled,^[7] the legs being quite invisible); and now I witnessed a curious action. I must say that just previously, when both birds were away, I had left my shelter in order to pick another nettle or two, and thus give myself a still clearer view, and I had then noticed that the two eggs were rather wide apart. As the bird now got on to them (which it did by pushing itself along the ground), it must, I think, have moved them still farther from each other. At any rate, it became necessary, in the bird's opinion, to alter their position, and in order to do this it went into a very peculiar attitude. It, as it were, stood up on its breast, with its tail raised almost perpendicularly in the air, so that it looked somewhat like a peg-top placed peg upwards on the broad end, the legs being at no time visible. Thus poised, the bird pressed with the under part of its broad beak, or, as one may say, with its chin, first one egg and then the other against and under its breast,^[8] and, so holding it, moved backwards and forwards over the ground, presenting a strange and unbirdlike appearance. The ground, however, was not even, and, despite the bird's efforts to get the eggs together, one of them (as I saw) rolled down a little declivity. At the bottom some good-sized pieces of fir-bark lay partly buried in the sand, and under one of these the egg became wedged. The bird was unable to get it out so as to bring it up the hill again to where the other egg lay, for the bark, by presenting an edge, prevented it from getting its chin against the further side of the wedged egg so as to press it against its breast as before, though making the most desperate efforts to do so. Wedging its head between the bark and the ground, the bird now stood still more perpendicularly upright on its breast (or rather, in this case, on its head) than it had done before, and in this position shoved and shouldered away most desperately. After each effort it would lie a little, as if exhausted, then waddle to the other egg, and settle itself upon it; but in a minute or two it would return to the one it had seemingly abandoned, and repeat its efforts to extricate it. I must have watched the bird make at least half a dozen of these attempts; but at last, after nearly half an hour, an idea occurred to it (or rather it altered its tactics then, as the idea may have come sooner). Again going to the properly placed egg, the bird, instead of covering it as before, began to move it to the other one in the way that I have described. "If the mountain will not go to Mohammed, Mohammed must go to the mountain." That was clearly the process of reasoning, and, seeing how set the bird's mind had been on one course of action, how it had toiled and struggled and returned to its efforts again and again, its sudden adoption of another plan shows, I think, both intelligence and versatility. It, in fact, acted just as an intelligent man would have acted. It tried to do the best thing till convinced it was impossible, and then did the second best. Still, we cannot any more, than in the case of the man, assume that the alternative course of action was not in the bird's mind from the beginning. Having got the two eggs together again, the bird appeared to me (for it was now too dark to observe accurately) to be trying to push the piece of bark away backwards with its wings, feet, and tail. It certainly propelled itself backwards against the edge, after the manner—observed by Jenner, and now, I believe, authenticated by photography—the young Cuckoo ejects its foster brothers and sisters from the nest. Finally, at 9.40, it flew away. I then went out to look, and saw that the bird had been successful in its efforts to a certain extent. The two eggs lay together, and though not quite on the same level, and though the piece of bark was still in the way of one of them, it might still, though not with ease, have sat on them both. However, had I left them as they were, I have no doubt that the birds would have worked away till matters were quite satisfactory. But having watched what had been taking place for a full half-hour at only three paces distance, and as, on the bird's return, it would have been too dark to see anything more, I thought I would assist them, and so smoothed down the declivity, and laid the eggs side by side on a flat surface. I must add that while the bird was thus struggling to extricate its egg it uttered from time to time a low querulous note.

At about ten one of the birds settled on a bush just in front of me, and sat there silently for some ten minutes, then flew and settled on the ground near eggs for a minute or two, and whilst there uttered a low guttural note. Finally, at 10.13, it came and settled itself quietly on to the eggs as I had placed them. This and my subsequent observations make me think that it was not the bird that had got into difficulties, but the other and more skilful one—the hen, no doubt—the cock bird being less perfect in the art of incubating.

June 26th.—Reached bush at 8.22 p.m., and found the bird sitting in the same position as night before. It seemed to be asleep, the eye being fast shut. The eggs appeared to have been moved slightly to one side, judging by where the bird sat.

8.34—Sitting bird relieved. Process exactly the same as on night before. The relieving bird came from neighbouring plantation quaw-eeing, and when near was answered by a gentle "churr" from the brooding bird. This latter's head was turned the other way, so that she could not have seen her mate as he flew up. Moreover, she opened her eyes for the first time at his "quaw-ee."

The new-come bird settled himself beside the brooding one as on previous night (same distance apart), and both of them churred, gently wagging their bodies from side to side. Then in a few seconds the relieved bird flew away (I think silently), and was followed a few seconds afterwards by the other one, which had not moved on to the eggs, or from where it had alighted. Upon going round the bush and looking at the eggs, I could not feel certain that they had been moved from where I placed them the previous night. The distance, I find, from where I sit to the eggs is just three paces.

8.53.—Bird flew near, and would have perched on the same little bush (just in front of me) as last night, but it saw me, I think, and, very little startled, settled on ground close by. Soon it flew up again, and came right down on to the eggs, settling itself in a different position to that at 8.22, the head being turned the other way. The eye, as far as I could see in the waning light, was again shut.

9.3.—The other bird flew up quaw-eeing as before, and, when near, the sitting one churred softly. He settled beside her silently whilst she continued to "churr," lifting up her tail and wagging it from side to side. I had not noticed the tail lifted so high before; it was raised considerably from the ground. In a few seconds the sitting bird flew off, and the other at once moved on to the eggs, but did not get on them properly, and began to pull them about with its beak (always the under part or chin), though not going into the curious attitude of the night before. The bird did not seem able to manage the eggs, and, after sitting hardly a minute on one only, flew off again, leaving them a couple of inches apart instead of side by side, as they had been left by the other.

9.22.—Bird settled on ground in neighbourhood of eggs, churred a little, and then flew away.

9.33.—Bird settled on ground near eggs, and in a second or two flew on to them, and got them together again, I think by stretching out a wing to one of them, and pulling it up to itself, but too dark now to see properly. At any rate, there was no clumsiness or uncouth attitude this time. This bird seemed master of the art of sitting; believe it to be the hen, and that it was the other (the cock bird) that got into difficulties with the eggs last night, and again this, though not to the same extent. If this be so, then the cock Nightjar is only a "'prentice han" at incubation. Had to leave now.

Note.—This same night (at 9.15) had several fine opportunities of watching pairs of birds chasing and playing about with each other high in the air (a beautiful sight), both of them clapping the wings above the back as an essential part of the performance. The clapping of the wings is as characteristic of this bird, as is the churring itself, and as much an expression of feeling between the male and female during the breeding season.^[9] (I shall subsequently allude to this point under "General Observations.")

June 27th.—(Bad weather all day; rainy and cloudy evening.) Arrived at 8.15. Heard birds churring already. Bird sitting. Head turned towards stalk, eyes closed, and seemingly asleep. When sitting the tips of the wings cross each other over the tail, which projects an inch or so beyond them.

8.50.—At the loud bang of a gun not far off ("making night hideous") the bird just opened its eyes (the one next to me at least) to the smallest possible extent, hardly noticeable at all, and then shut them again. They had been closed until then, but for one little blink.

8.40.—The eyes still fast closed. A bird flew by quite near quaw-eeing, but the sitting bird took no notice. Again the bird (or another one) flew by, still closer, calling as before—no notice. But a little farther on he was answered by a soft "churr" from the ground, his mate, as I concluded, sitting on the eggs. He did not settle, but circled round several times, quaw-eeing and clapping his wings, the other bird answering with "churrs," and also a soft croodling note, very expressive of satisfaction. Note that my sitting bird paid no attention to the greeting of a bird, not her mate, which greeting was not addressed to her, though uttered quite close—in fact, just over her head.

8.55.—A bird flew near by quaw-eeing, and the sitting one answered with a very subdued and low "churr" (the lowest I have yet heard). The bird flew on without settling. The sitting bird had not opened its eyes properly till then. I seemed to recognize the note made by the flying bird, but wondered at the "churr" being so low and so quickly ended.

Query.—Was it a mistake on the sitting bird's part? It sounded like, "Was that——? No. I thought I recognized his voice."

Five or six birds now flew near about, seeming to chase and sport with each other. Some flew quite close, but to their cries the sitting bird made no response.

9.10.—Partner still not come. Sitting bird now became wakeful, moving her head round first one way and then another; then flew off so suddenly that I thought she must have caught sight of me through the screen. In all probability, however, this was not the case.

Walked about a little, and returned to screen at 9.30.

About 9.40 a bird came and sat on the same alder-stump as night before (some four feet high, and only a few feet from where I sat, with very little cover between—last night hardly any). It sat there about ten minutes, uttering during a good part of the time a low guttural note, perhaps something like "ho-oo ho-oo ho-oo," but impossible to write it. No doubt whatever as to this; heard it as plainly at that distance as if the bird had churred. At 9.50 bird flew from its stump round my bush and on to its eggs, which suddenly disappeared, but it was too dark to see the bird on them.

June 28th.—Arrived at 11.20 a.m., and found bird sitting, the head this time turned straight towards me, which had not been the case before. Evidently dozing. One eye, however, was a little more open than the other, showing just a black slit. A Blow-fly was walking over its head and beak, and the bird took no notice. Flies afterwards settled on it from time to time, and walked about over it. When they went over its eyes the bird blinked the one or the other of them, or just twitched without opening it. A large green fly flew right at one of her eyes, when, without opening it, she gave her head a jerk.

Three times, whilst sitting here, I observed the feathers just under the bird's throat to be quivering, whilst the beak was very slightly (as slightly as possible) open. I satisfied myself that this motion of the feathers was produced by the bird itself, and not by the wind, for it was only occasional, whereas the wind was continuous. They were often still during a sudden gust of wind, and, moreover, why should the wind have moved just those feathers and no others? I could hear no sound, though I believe there was one. The bird perhaps was dreaming and churring in its dreams.

Left at 1.10 p.m.

7.25 p.m.—(No rain during day and sunny, but now cloudy and almost raining.) Bird sitting in nearly same position as in the morning. Eyes shut.

8.25.—Sitting bird relieved. Its partner flew up quaw-eeing, and when near was answered with a slight "churr." It settled down a few inches off, and then both birds churred, wagging their tails from side to side in the usual manner. In a second or two the sitting bird flew off, silently at first, but when she had gone a little way gave a "quaw-ee." The other one sat where he was for a second or so (not going on to the eggs), and then flew after her.

9.28.—Bird began to "churr" on eggs,^[10] and did so at short intervals in little bursts for a few minutes, as if it heard the voice of its mate, which I believe it did, though I could not.

9.50.—Other bird settled on elder-stump near, and kept uttering a peculiar single note like "quo quo," which was answered (but only occasionally) by a "churr" from the sitting bird.

9.53.—The bird on the stump flew near to the one sitting, which rose and joined it, and then both flew off quaw-eeing.

9.55.—Bird flew on to stump, and kept uttering low single note. In less than a minute it flew to eggs and sat on them. Was still sitting at 10.35, when I came away.

June 29th.—(Fine day, sunny.)

12.7 p.m.—Found bird sitting in same position as yesterday, head towards me, affording a very good front view. The bird kept constantly quivering the feathers of the throat. Just those particular feathers which make a sort of lappet dividing the throat and breast, were in a continual state of trembling, or vibration. The beak was very slightly open. I could catch no sound, except just once, for a single moment, the faintest possible "churr." There was a considerable wind, and the nettles all around the bird were swayed backwards and forwards (though the low plants were not to nearly the same extent). Yet no other feather of the bird's body was stirred, and I particularly noticed that one which projected a little from the side of the throat rather lower down was quite steady. Moreover, with the nettles still swaying in the wind, the tremulous motion I speak of would stop for a instant or two, and then recommence. During this time that eye of the bird which I could see was either shut or very slightly opened. Splendid view of the bird brooding to-day. The feathers of the breast are pressed outwards over the eggs, so that the bird seems sitting on a square pedestal of its own feathers. Could see one of the eggs projecting from under the feathers. Left at 12.44.

8.48 p.m.—Bird sitting. Position changed since morning. Wings and tail crossing dried stalk, as at first. Eyes closed. Other bird settled nine or ten paces from eggs on ground. Churred a little, and sat still. Sitting bird did not answer, seeming to be asleep. About nine the partner flew up and sat beside the sitting bird, who then just churred a little. The other did not "churr," and almost immediately flew away quaw-eeing. The other still sat on, and seemed to go to sleep again.

9.15.—The partner again settled on ground near and churred a little, the sitting bird taking no notice. The latter now moved, and two little white fluffy things (as at that distance and in the waning light they seemed to me to be) scrambled from beneath her. They were the chicks.

(To be continued.)

 

Footnotes

1. As it flew off no doubt, for this note "quaw-ee quaw-ee" is, according to my observation, only made in the air.
2. One bird—no doubt the hen—sits on the eggs all day, and does by far the greater part of the night-sitting also.
3. Only as it flies off, I believe.
4. Except blinking the eyes.
5. In concluding "General Observations."
6. "This churring note... is said to be confined to the male bird, and only uttered when it is perched" (cf. Seebohm, 'History of British Birds'). "The well-known vibrating 'churr' is believed to be uttered by the male only" (cf. Howard Saunders, 'Illustrated Manual of British Birds'). "As the season advances the song of the cock," &c. (cf. Prof. Newton in 'Ency. Brit.' (last edition), and also in 'Dictionary of Birds').
7. This word, though I could think of no better one at the time, does not properly express the bird's motion. As will appear later on, the Nightjar is quite at home on the ground.
8. In such a position the bristles fringing the gape would help to keep the egg secure, whilst the toothed claw would help the bird to get a grip on the ground in its strained attitude; but I do not estimate this as any special adaptation in relation to these odd and probably infrequent proceedings.
9. At least in relation with the bird's nuptial activities. Compare aerial antics of Peewits in the spring. This most salient peculiarity of the Nightjar appears to have been most inadequately noticed. I have not met with an interesting remark in regard to it.
10. I have omitted to note bird's return.