The Foot-path Way Part 5

It would seem impossible, at this late day, to say anything new about so familiar a bird; but the robin has one interesting and remarkable habit, to which there is no allusion in any of our systematic ornithological treatises, so far as I am aware, although many individual observers must have taken notice of it. I mean the habit of roosting at night in large flocks, while still on its breeding grounds, and long before the close of the breeding season.[14]

[14] Mr. William Brewster has been aware of this habit for twenty-five years, but, like myself, has never seen it mentioned in print. He devotes to it a paper in _The Auk_ for October, 1890, to which I am happy to refer readers who may wish a more thorough discussion of the matter than I have been able to give. My own paper was printed at the same time, in _The Atlantic Monthly_, and had been accepted by the editor before I knew of Mr. Brewster's intention to write. References to a roost in Belmont, Ma.s.s., discovered by Mr. Brewster six years before, are frequent in the following pages.

Toward the end of summer, two years ago, I saw what looked like a daily pa.s.sage back and forth of small companies of robins. A friend, living in another town, had noticed similar occurrences, and more than once we discussed the subject; agreeing that such movements were probably not connected in any way with the grand southward migration, which, so far as we could judge, had not yet commenced, but that the birds must be flying to and from some nightly resort. The flocks were small, however, and neither of us suspected the full significance of what we had seen.

On the 19th of July, 1889, the same friend informed me that one of our Cambridge ornithologists had found a robin roost in that city,--a wood in which great numbers of birds congregated every night. This led me to keep a sharper eye upon my own robins, whom I had already noticed repeating their previous year's manoeuvres. Every evening, shortly before and after sunset, they were to be seen flying, now singly, now by twos and threes, or even by the half dozen, evidently on their way to some rendezvous. I was suspicious of a rather distant hill-top covered with pine-trees; but before I could make it convenient to visit the place at the proper hour, I discovered, quite unexpectedly, that the roost was close by the very road up and down which I had been walking; an isolated piece of swampy wood, a few acres in extent, mostly a dense growth of gray birches and swamp white oaks, but with a sprinkling of maples and other deciduous trees. It is bounded on the further side by a wet meadow, and at the eastern end by a little ice-pond, with a dwelling-house and other buildings beside it, all within a stone's throw of the wood.

This discovery was made on the evening of July 25th, and I at once crossed a narrow field between the wood and the highway, and pushed in after the birds. It was too dark for me to see what was going on, but as I brushed against the close branches the robins set up a lively cackling, and presently commenced flying from tree to tree before me as I advanced, though plainly with no intention of deserting their quarters. The place was full of them, but I could form no estimate of their number.

On the following evening I took my stand upon a little knoll commanding the western end of the wood. According to my notes, the birds began to arrive about sunset,--but this was pretty certainly an error,--and though I did not undertake an exact count until the flight was mainly over, it seemed likely that at least three hundred pa.s.sed in at that point. This would have made the total number twelve hundred, or thereabout, on the a.s.sumption that my outlook had covered a quarter of the circuit. After the flight ceased I went into the wood, and from the commotion overhead it was impossible not to believe that such a calculation must be well within the truth.

The next day was rainy, but on the evening of the 28th I stood by the sh.o.r.e of the pond, on the eastern side of the wood, and made as accurate a count as possible of the arrivals at that point. Unfortunately I was too late; the robins were already coming. But in fifty minutes, between 6.40 and 7.30, I counted 1072 birds. They appeared singly and in small flocks, and it was out of the question for me to make sure of them all; while I was busy with a flock on the right, there was no telling how many might be pa.s.sing in on the left. If my observations comprehended a quarter of the circle, and if the influx was equally great on the other sides (an a.s.sumption afterward disproved), then it was safe to set the whole number of birds at five thousand or more. Of the 1072 actually seen, 797 came before the sunset gun was fired,--a proportion somewhat larger than it would have been had the sky been clear.

On the afternoon of the 29th I again counted the arrivals at the eastern end; but though I set out, as I thought, in good season, I found myself once more behind time. At 6.30 robins were already dropping in, notwithstanding the sky was cloudless. In the first five minutes eighteen birds appeared; at sunset 818 had been counted; and at 7.30, when I came away, the figures stood at 1267. "The robins came more rapidly than last night," I wrote in my notebook, "and for much of the time I could keep watch of the southeastern corner only. My vision then covered much less than a quarter of the circuit; so that if the birds came as freely from other directions, at least five thousand must have entered the wood between 6.30 and 7.30. As long as it was light they avoided pa.s.sing directly by me, going generally to the left, and slipping into the roost behind some low outlying trees; though, fortunately, in doing this they were compelled to cross a narrow patch of the illuminated western sky. I suspect that the number increases from night to night. Between 6.40 and 7.30, 1235 birds came, as compared with 1072 last evening."

Two days afterward (July 31st) I went to the western end of the wood, and found the influx there much smaller than on the opposite side; but I arrived late, and made a partial count only. After sunset 186 birds were seen, whereas there had been 455 entries at the eastern end, two nights before, during the same time.

Thus far I had always been too late to witness the beginning of the flight. On the evening of August 1st I resolved to be in season. I reached the border of the pond at 5.15, and at that very moment a single robin flew into the wood. No others were seen for eighteen minutes, when three arrived together. From this time stragglers continued to appear, and at 6.30 I had counted 176. In the next ten minutes 180 arrived; in the next five minutes, 138. Between 6.45 and 7, I counted 549; then, in six minutes, 217 appeared. At 7.25, when I concluded, the figures stood at 1533 birds. For about twenty minutes, as will be noticed, the arrivals were at the rate of thirty-six a minute. Throughout the thickest of the flight I could keep a lookout upon only one side of me, and, moreover, the gathering darkness was by that time making it more and more difficult to see any birds except such as pa.s.sed above the dark tree line; and from what went on just about me, it was evident that the number of arrivals was increasing rather than diminis.h.i.+ng as my count fell off. There seemed to be no good reason for doubting that at least two thousand robins entered the wood at the eastern end.

Two nights later I stationed myself in the meadow southwest of the roost. Here I counted but 935 entries. The movement appeared to be fully as steady as on the opposite side, but as darkness came on I found myself at a great disadvantage; a hill occupied the background, giving me no illuminated sky to bring the birds into relief, so that I could see only such as pa.s.sed close at hand. Of the 935 birds, 761 came before seven o'clock, but it was reasonably certain that the flight afterward was nearly or quite as great, only that I wanted light wherewith to see it.

On the evening of August 4th I went back to the eastern end, and as the sky was perfectly clear I hoped to make a gain upon all my previous figures. But the fair weather was perhaps a hindrance rather than a help; for the robins came later than before, and more in a body, and continued to arrive long after it was impossible to see them. I counted 1480,--53 less than on the 1st.

I attempted no further enumeration until the 18th. Then, in an hour and ten minutes, 1203 birds were seen to enter the roost at the eastern end.

But they arrived more than ever in flocks, and so late that for much of the time I missed all except the comparatively small number that pa.s.sed in my immediate vicinity. Many were flying at a great height,--having come from a long distance, as I inferred,--and sometimes I knew nothing of their approach till they dropped out of the sky directly over the wood. On this occasion, as well as on many others,--but chiefly during the latter part of the season,--it was noticeable that some of the robins appeared to be ignorant of the precise whereabouts of the roost; they flew past it at first, and then, after more or less circling about, with loud cackling, dived hurriedly into the wood. I took special note of one fellow, who came from the south at a great alt.i.tude, and went directly over the wood. When he was well past it he suddenly pulled himself up, as if fancying he had caught a signal. After a moment of hesitation he proceeded on his northerly course, but had not gone far before he met half a dozen birds flying south. Perhaps he asked them the way. At all events, he wheeled about and joined them, and in half a minute was safe in port. He had heard of the roost, apparently (how and where?), but had not before visited it.

This count of August 18th was the last for nearly a month, but I find a minute of August 27th stating that, while walking along the highway on the westerly side of the roost,--the side that had always been the least populous,--I saw within less than two minutes (as I calculated the time) more than eighty robins flying toward the wood. Up to this date, then, there could not have been any considerable falling off in the size of the gathering. Indeed, from my friend's observations upon the Belmont roost, to be mentioned later, it seems well-nigh certain that it was still upon the increase.

Toward the close of August I became interested in the late singing of several whippoorwills, and so was taken away from the robins' haunt at the hour of sunset. Then, from the 5th to the 13th of September, I was absent from home. On the night of my return I went to the sh.o.r.e of the pond, where, on the 1st of August, I had counted 1533 entries. The weather was favorable, and I arrived in good season and remained till the stars came out, but I counted only 137 robins! It was plain that the great majority of the congregation had departed.

As I have said, there was little to be learned by going into the wood after the robins were a.s.sembled. Nevertheless I used frequently to intrude upon them, especially as friends or neighbors, who had heard of my "discovery," were desirous to see the show. The prodigious cackling and rustling overhead seemed to make a deep impression upon all such visitors, while, for myself, I should have had no difficulty in crediting the statement had I been told that _ten thousand_ robins were in the treetops. One night I took two friends to the place after it was really dark. All was silent as we felt our way among the trees, till, suddenly, one of the trio struck a match and kindled a blaze of dry twigs. The smoke and flame speedily waked the sleepers; but even then they manifested no disposition to be driven out.

For curiosity's sake, I paid one early morning visit to the roost, on the 30th of July. It would be worth while, I thought, to see how much music so large a chorus would make, as well as to note the manner of its dispersion. To tell the truth, I hoped for something spectacular,--a grand burst of melody, and then a pouring forth of a dense, uncountable army of robins. I arrived about 3.40 (it was still hardly light enough to show the face of the watch), and found everything quiet. Pretty soon the robins commenced cackling. At 3.45 a song sparrow sang, and at the same moment I saw a robin fly out of the wood. Five minutes later a robin sang; at 3.55 another one flew past me; at four o'clock a few of the birds were in song, but the effect was not in any way peculiar,--very much as if two or three had been singing in the ordinary manner. They dispersed precisely as I had seen them gather: now a single bird, now two or three, now six, or even ten. A casual pa.s.ser along the road would have remarked nothing out of the common course.

They flew low,--not as if they were starting upon any prolonged flight,--and a goodly number alighted for a little in the field where I was standing. Shortly before sunrise I went into the wood and found it deserted. The robin is one of our noisiest birds. Who would have believed that an a.s.sembly of thousands could break up so quietly? Their behavior in this regard may possibly have been influenced by prudential considerations. I have said that many of them seemingly took pains to approach the roost indirectly and under cover. On the westerly side, for example, they almost invariably followed a line of bushes and trees which runs toward the roost along the edge of the meadow, even though they were obliged sharply to alter their course in so doing.

All this time I had been in correspondence with my friend before referred to, who was studying a similar roost,[15]--in Belmont,--which proved to be more populous than mine, as was to be expected, perhaps, the surrounding country being less generally wooded. It was a mile or more from his house, which was so situated that he could sit upon his piazza in the evening and watch the birds streaming past. On the 11th of August he counted here 556 robins, of which 336 pa.s.sed within five minutes. On the 28th he counted 1180, of which 456 pa.s.sed within five minutes,--ninety-one a minute! On the 2d of September, from a knoll nearer the roost, he counted 1883 entries.

[15] This roost was discovered by Mr. William Brewster, in August, 1884, as already mentioned.

This gathering, like the one in Melrose, was greatly depleted by the middle of September. "Only 109 robins flew over the place to-night," my correspondent wrote on the 25th, "against 538 September 4th, 838 August 30th, and 1180 August 28th." Two evenings later (September 27th) he went to the neighborhood of the roost, and counted 251 birds,--instead of 1883 on the 2d. Even so late as October 9th, however, the wood was not entirely deserted. During the last month or so of its occupancy, the number of the birds was apparently subject to sudden and wide fluctuations, and it seemed not unlikely that travelers from the north were making a temporary use of the well-known resort. It would not be surprising if the same were found to be true in the spring. In April, 1890, I saw some things which pointed, as I thought, in this direction, but I was then too closely occupied to follow the matter.

How early in the season does this nightly flocking begin? This question often presented itself. It was only the middle of July when the Cambridge roost was found in full operation, though at that time many robins must still have had family duties, and some were probably building new nests. Next summer, we said, we would try to mark the beginnings of the congregation.

My own plans to this end came near being thwarted. In December I was dismayed to see the owner of the wood cutting it down. Happily some kind power stayed his hand when not more than a third of the mischief was done, and on the 29th of June, 1890, while strolling homeward along the highway, listening to the distant song of a veery, I noticed within five or ten minutes seventeen robins making toward the old rendezvous. On the following evening I stood beside the ice-pond and saw one hundred and ninety-two robins enter the wood. The flight had begun before my arrival, and was not entirely over when I came away. Evidently several hundreds of the birds were already pa.s.sing their nights in company. In my ignorance, I was surprised at the early date; but when I communicated my discovery to the Belmont observer, he replied at once that he had noticed a movement of the same kind on the 11th of June. The birds, about a dozen, were seen pa.s.sing his house.

Thinking over the matter, I began to ask myself--though I hesitate about making such a confession--whether it might not be the adult males who thus unseasonably went off to bed in a crowd, leaving their mates to care for eggs and little ones. At this very moment, as it happened, I was watching with lively sympathy the incessant activities of a female humming-bird, who appeared to be bringing up a family (two very hungry nestlings), with no husband to lift a finger for her a.s.sistance; and the sight, as I fear, put me into a cynical mood. Male robins were probably like males in general,--lovers of clubs and s.h.i.+rkers of home duties.

Indeed, a friend who went into the roost with me, one evening, remarked upon the continual cackling in the treetops as "a very social sound;"

and upon my saying something about a sewing circle, he answered, quite seriously, "No, it is rather like a gentleman's club." But it would have been unscientific, as well as unchristian, to entertain an hypothesis like this without putting its soundness to some kind of test. I adopted the only plan that occurred to me,--short of rising at half past two o'clock in the morning to see the birds disperse. I entered the wood just before the a.s.semblage was due (this was on the 9th of July), and took a sheltered position on the eastern edge, where, as the robins flew by me, or alighted temporarily in the trees just across the brook, they would have the sunlight upon their b.r.e.a.s.t.s. Here, as often as one came sufficiently near and in a sufficiently favorable light, I noted whether it was an adult, or a streaked, spotted bird of the present season. As a matter of course, the number concerning which this point could be positively determined under such conditions was very small,--only fifty-seven altogether. Of these, forty-nine were surely birds of the present summer, and only eight unmistakable adult males. If any adult females came in, they pa.s.sed among the unidentified and uncounted.[16] I was glad I had made the test. As a kind-hearted cynic (I confess to being nothing worse than this), I was relieved to find my misanthropic, or, to speak more exactly, my misornithic, notions ill founded. As for the sprinkling of adult males, they may have been, as a "friend and fellow woodlander" suggests, birds which, for one reason or another, had taken up with the detestable opinion that "marriage is a failure."

[16] A week later, my correspondent reported a similar state of things at the Belmont roost. "A very large proportion of the birds are spotted-breasted young of the year, but occasionally I have detected an adult male." He examined the birds at near range, and at rest, after they had come into the roost in the earlier part of the evening.

During the month of July, 1890, I made frequent counts of the entries at the eastern end of the roost, thinking thus to ascertain in a general way the rate at which its population increased. On the whole, the growth proved to be fairly steady, in spite of some mysterious fluctuations, as will be seen by the following table:--

July 3 247 " 5 383 " 6 356 " 10 765 " 12 970 " 14 1120 " 16 1064 " 17 1333 " 19 1584 " 22 1520 " 23 1453 " 27 2314

After July 6th all the enumerations were made with the help of another man, though we stood side by side, and covered no more ground than I had hitherto attempted to compa.s.s alone. The figures of the 27th were far in excess of any obtained in 1889, and for a day I was disposed to take seriously the suggestion of a friend that some other roost must have been broken up and its members turned into the Melrose gathering. But on the evening of the 28th I tried a count by myself, and made only 1517 birds! The conditions were favorable, and the robins came, as they had come the night before, in flocks, almost in continuous streams. The figures had fallen off, not because there were fewer birds, but because I was unable to count them. They were literally too many for me. The difficulties of the work, it should be explained, are greatly enhanced by the fact that at the very corner where the influx is largest none of the low-flying birds can be seen except for a second or two, as they dart across a bit of sky between the roost and an outlying wood. To secure anything like a complete census, this point must be watched continuously; and meantime birds are streaming in at the other corner and shooting over the distracted enumerator's head, and perhaps dropping out of the sky. I conclude, therefore, not that the roost had increased in population, but that my last year's reckoning was even more inadequate than I then supposed. Even with two pairs of eyes, it is inevitable that mult.i.tudes of birds should pa.s.s in unnoticed, especially during the latter half of the flight. I have never had an a.s.sistant or a looker-on to whom this was not perfectly apparent.

As I stood night after night watching the robins stream into this little wood,--no better, surely, than many they had pa.s.sed on their way,--I asked myself again and again what could be the motive that drew them together. The flocking of birds for a long journey, or in the winter season, is less mysterious. In times of danger and distress there is no doubt a feeling of safety in a crowd. But robins cannot be afraid of the dark. Why, then, should not each sleep upon its own feeding grounds, alone, or with a few neighbors for company, instead of flying two or three miles, more or less, twice a day, simply for the sake of pa.s.sing the night in a general roost?

Such questions we must perhaps be content to ask without expecting an answer. By nature the robin is strongly gregarious, and though his present mode of existence does not permit him to live during the summer in close communities,--as marsh wrens do, for example, and some of our swallows,--his ancestral pa.s.sion for society still a.s.serts itself at nightfall. Ten or twelve years ago, when I was bird-gazing in Boston, there were sometimes a hundred robins at once about the Common and Garden, in the time of the vernal migration. By day they were scattered over the lawns; but at sunset they gathered habitually in two or three contiguous trees, not far from the Frog Pond and the Beacon Street Mall (I wonder whether the same trees are still in use for the same purpose), where, after much noise and some singing, they retired to rest,--if going to sleep in a leafless treetop can be called retiring.

Whatever the origin and reason of this roosting habit, I have no doubt that it is universal. Middles.e.x County birds cannot be in any respect peculiar. Whoever will keep a close eye upon the robins in his neighborhood, in July and August, will find them at sunset flocking to some general sleeping-place.

It would be interesting to know how far they travel at such times. The fact that so many hundreds were to be seen at a point more than a mile away from the Belmont roost is significant; but I am not aware that any one has yet made a study of this part of the subject. My own birds seemed to come, as a rule, by easy stages. In the long narrow valley east of the roost, where I oftenest watched their approach, they followed habitually--not invariably--a zigzag route, crossing the meadow diagonally, and for the most part alighting for a little upon a certain wooded hill, whence they took a final flight to their nightly haven, perhaps a quarter of a mile beyond. Farther down the valley, a mile or more from the roost, birds were to be seen flying toward it, but I found no place at which a general movement could be observed and large numbers counted.

As to the size of these nightly gatherings, it seems wisest not to guess; though, treating the subject in this narrative manner, I have not scrupled to mention, simply as a part of the story, some of my temporary surmises. What I am told of the Belmont wood is true also of the one in Melrose: its shape and situation are such as to make an accurate census impossible, no matter how many "enumerators" might be employed. It could be surrounded easily enough, but it would be out of the question to divide the s.p.a.ce among the different men so that no two of them should count the same birds. At present it can only be said that the robins are numbered by thousands; in some cases, perhaps, by tens of thousands.

THE Pa.s.sING OF THE BIRDS.

"The Bird of Time has but a little way To flutter--and the Bird is on the Wing."

OMAR KHAYYaM.

By the first of August the bird-lover's year is already on the wane. In the chestnut grove, where a month ago the wood thrush, the rose-breasted grosbeak, and the scarlet tanager were singing, the loiterer now hears nothing but the wood pewee's pensive whistle and the sharp monotony of the red-eyed vireo. The thrasher is silent in the berry pasture, and the bobolink in the meadow. The season of jollity is over. Orioles, to be sure, after a month of silence, again have fits of merry fifing. The field sparrow and the song sparrow are still in tune, and the meadow lark whistles, though rarely. Catbirds still practice their feeble improvisations and mimicries in the thickets along the brooksides as evening comes on, and of the mult.i.tudes of robins a few are certain to be heard warbling before the day is over. Goldfinches have grown suddenly numerous, or so it seems, and not infrequently one of them breaks out in musical canary-like twitterings. On moonlight evenings the tremulous, haunting cry of the screech-owl comes to your ears, always from far away, and if you walk through the chestnut grove aforesaid in the daytime you may chance to catch his faint, vibratory, tree-frog whistle. For myself, I never enter the grove without glancing into the dry top of a certain tall tree, to see whether the little rascal is sitting in his open door. More than half the time he is there, and always with his eye on me. What an air he has!--like a judge on the bench! If I were half as wise as he looks, these essays of mine would never more be dull. For his and all other late summer music let us be thankful; but it is true, nevertheless, that the year is waning. How short it has been! Only the other day the concert opened, and already the performers are uneasy to be gone. They have crowded so much into so brief a s.p.a.ce! The pa.s.sion of a life-time into the quarter of a year!

They are impatient to be gone, I say; but who knows how many of them are gone already? Where are the blue golden-winged warblers that sang daily on the edge of the wood opposite my windows, so that I listened to them at my work? I have heard nothing of their rough _dsee, dsee_ since the 21st of June, and in all that time have seen them but once--a single bird, a youngling of the present year, stumbled upon by accident while pus.h.i.+ng my way through a troublesome thicket on the first day of August.

Who knows, I say, how many such summer friends have already left us? An odd coincidence, however, warns me at this very moment that too much is not to be made of merely negative experiences; for even while I was penciling the foregoing sentence about the blue golden-wing there came through the open window the hoa.r.s.e upward-sliding chant of his close neighbor, the prairie warbler. I have not heard that sound before since the 6th of July, and it is now the 22d of August. The singers had not gone, I knew; I saw several of them (and beautiful creatures they are!) a few days ago among the pitch pines; but why did that fellow, after being dumb for six or seven weeks, pipe up at that precise moment, as if to punctuate my ruminations with an interrogation point? Does he like this dog-day morning, with its alternate shower and suns.h.i.+ne, and its constant stickiness and heat? In any case I was glad to hear him, though I cannot in the spirit of veracity call him a good singer. Whist! There goes an oriole, a gorgeous creature, flas.h.i.+ng from one elm to another, and piping in his happiest manner as he flies. It might be the middle of May, to judge from his behavior. _He_ likes dog-day weather, there can be no question of that, however the rest of the world may grumble.

This is a time when one sees many birds, but few species. Bluebirds are several times as abundant as in June. The air is sweet with their calls at this moment, and once in a while some father of the flock lets his happiness run over in song. One cannot go far now without finding the road full of chipping sparrows, springing up in their pretty, characteristic way, and letting the breeze catch them. The fences and wayside apple-trees are lively with kingbirds and phoebes. I am already watching the former with a kind of mournful interest. In ten days, or some such matter, we shall have seen the last of their saucy antics. Gay tyrants! They are among the first birds of whom I can confidently say, "They are gone;" and they seem as wide-awake when they go as when they come. Being a man, I regret their departure; but if I were a crow, I think I should be for observing the 31st of August as a day of annual jubilee.

A few years ago, in September, I saw the white-breasted swallows congregated in the Ipswich dunes,--a sight never to be forgotten. On the morning of the 9th, the fourth day of our visit, a considerable flock--but no more, perhaps, than we had been seeing daily--came skimming over the marshes and settled upon a sand-bar in the river, darkening it in patches. At eight o'clock, when we took the straggling road out of the hills, a good many--there might be a thousand, I guessed--sat, upon the fence wires, as if resting. We walked inland, and on our return, at noon, found, as my notes of the day express it, "an innumerable host, thousands upon thousands," about the landward side of the dunes. Fences and hayc.o.c.ks were covered. Mult.i.tudes were on the ground,--in the bed of the road, about the bare spots in the marsh, and on the gray faces of the hills. Other mult.i.tudes were in the bushes and low trees, literally loading them. Every few minutes a detachment would rise into the air like a cloud, and anon settle down again. As we stood gazing at the spectacle, my companion began chirping at a youngster who sat near him on a post, as one might chirp to a caged canary. The effect was magical. The bird at once started toward him, others followed, and in a few seconds hundreds were flying about our heads. Round and round they went, almost within reach, like a cloud of gnats. "Stop! stop!"

cried my companion; "I am getting dizzy." We stopped our squeakings, and the cloud lifted; but I can see it yet. Day after day the great concourse remained about the hills, till on the 13th we came away and left them. The old lighthouse keeper told me that this was their annual rendezvous. He once saw them circle for a long time above the dunes, for several hours, if I remember right, till, as it seemed, all stragglers had been called in from the beach, the marsh, and the outlying gra.s.sy hills. Then they mounted into the sky in a great spiral till they pa.s.sed out of sight; and for that year there were no more swallows.

This, he insisted, took place in the afternoon, "from three to four o'clock." He was unquestionably telling a straightforward story of what he himself had seen, but his memory may have been at fault; for I find it to be the settled opinion of those who ought to know, that swallows migrate by day and not by night, while the setting out of a great flock late in the afternoon at such a height would seem to indicate a nocturnal journey. Morning or evening, I would give something to witness so imposing a start.

The recollection of this seaside gathering raises anew in my mind the question why, if swallows and swifts migrate exclusively in the daytime, we so rarely see anything of them on the pa.s.sage. Our Ipswich birds were all tree swallows,--white-breasted martins,--and might fairly be supposed to have come together from a comparatively limited extent of country. But beside tree swallows there are purple martins, barn swallows, sand martins, cliff swallows, and chimney swifts, all of which breed to the northward of us in incalculable numbers. All of them go south between the middle of July and the first of October. But who in New England has ever seen any grand army of them actually on the wing?

Do they straggle along so loosely as to escape particular notice? If so, what mean congregations like that in the Ipswich dunes? Or are their grand concerted flights taken at such an alt.i.tude as to be invisible?

On several afternoons of last September, this time in an inland country, I observed what might fairly be called a steady stream of tree swallows flying south. Twice, while gazing up at the loose procession, I suddenly became aware of a close bunch of birds at a prodigious height, barely visible, circling about in a way to put a count out of the question, but evidently some hundreds in number. On both occasions the flock vanished almost immediately, and, as I believed, by soaring out of sight. The second time I meant to a.s.sure myself upon this point, but my attention was distracted by the sudden appearance of several large hawks within the field of my gla.s.s, and when I looked again for the swallows they were nowhere to be seen. Were the stragglers which I had for some time been watching, flying high, but well within easy ken, and these dense, hardly discernible cl.u.s.ters--hirundine nebulae, as it were--were all these but parts of one innumerable host, the main body of which was pa.s.sing far above me altogether unseen? The conjecture was one to gratify the imagination. It pleased me even to think that it _might_ be true. But it was only a conjecture, and meantime another question presented itself.

When this daily procession had been noticed for two or three afternoons, it came to me as something remarkable that I saw it always in the same place, or rather on the same north and south line, while no matter where else I walked, east or west, not a swallow was visible. Had I stumbled upon a regular route of swallow migration? It looked so, surely; but I made little account of the matter till a month afterward, when, in exactly the same place, I observed robins and bluebirds following the same course. The robins were seen October 26th, in four flocks, succeeding each other at intervals of a few minutes, and numbering in all about 130 birds. They flew directly south, at a moderate height, and were almost certainly detachments of one body. The bluebird movement was two days later, at about the same hour, the morning being cold, with a little snow falling. This time, too, as it happened, the flock was in four detachments. Three of these were too compact to be counted as they pa.s.sed; the fourth and largest one was in looser order and contained a little more than a hundred individuals. In all, as well as I could guess, there might have been about three hundred birds. They kept a straight course southward, flying high, and with the usual calls, which, in autumn at least, always have to my ears a sound of farewell. Was it a mere coincidence that these swallows, bluebirds, and robins were all crossing the valley just at this point?

This question, too, I count it safer to ask than to answer, but all observers, I am sure, must have remarked so much as this,--that birds, even on their migrations, are subject to strong local preferences. An ornithologist of the highest repute a.s.sures me that his own experience has convinced him so strongly of this fact that if he shoots a rare migrant in a certain spot he makes it a rule to visit the place again a year afterward on the same day, and, if possible, at the same hour of the day. Another friend sends me a very pretty story bearing upon the same point. The bird of which he speaks, Wilson's black-cap warbler, is one of the less common of our regular Ma.s.sachusetts migrants. I count myself fortunate if I see two or three specimens during its spring or autumn pa.s.sage. My correspondent shall tell the story for himself.

"While I was making the drawings for the 'Silva,' at the old Dwight house, I was in the habit of taking a turn every pleasant day in the gardens after my scanty lunch. On the 18th of May, 1887, in my daily round I saw a Wilson's black-cap for the first time in my life. He was in a bush of _Spiraea media_, which grew in the midst of the rockery, and allowed me to examine him at near range with no appearance of fear.

Naturally I made a note of the occurrence in my diary, and talked about it with my family when I got home. The seeing of a new bird always makes a red-letter day.

"The next spring, as I was looking over my notebook of the previous year, I came upon my entry of May 18th, and thought I would be on the lookout for a black-cap on that date. Several times during the morning I thought of the matter, and after my lunch I sauntered into the rockery just as I had done the year before. Imagine my start when there, in the very same bush, was the black-cap peering at me; and I found on looking at my watch that it was precisely the same hour,--half past one! I rubbed my eyes and pinched myself to make sure it was not a dream. No, it was all real. Of course, I thought the coincidence very singular, and talked about it, not only with my family, but also with other people.