Bird studies with a camera

by Frank M. Chapman

“As the sun rose over the Palisades few birds were on the wing, but great flocks were perched in the reeds on the banks of the creek, and as in my canoe I drifted slowly up to them, they seemed unmindful of my presence, when, as though at a signal, they arose as one bird, and after hovering lightly overhead returned to the reeds.

“The tide was low, and along the shore several Sora Rail were feeding, and, as carried by the tide I floated noiselessly by, they paused in their search for food, and with tails upraised regarded me with evident astonishment. A mink approached the shores of a small inflowing stream, hesitated, then plunged in, crossed, and disappeared in the tall grasses on the opposite side. The air was vocal with the calls of Red-winged Blackbirds, the chink of Bobolinks, and the rattle of Swamp Sparrows.

“On a reed-grown point below was another great army of Swallows. With surprising regularity a detachment left it every fifteen minutes; thus, birds left at 6, 6.15, 6.30, and 6.45, when the reeds were deserted. The departing birds did not arise alone, but the entire flock arose at once, then divided into two flocks, one of which flew northward while the other returned to the reeds. Many of the departing birds alighted on the reeds farther up the creek; their numbers constantly received additions from the ranks of passing birds, and thus new flocks were formed.

“At eight o’clock the last Swallows had left the reeds in my vicinity, but birds were constantly passing toward the north, and this straggling flight continued until nine o’clock, when again the marshes appeared deserted.”

Subsequent observations have been made largely from a road crossing the marsh, the telegraph and electric-light wires which border it being the resting place of vast numbers of Swallows, both at night and in the morning. Particularly do they throng the wires near the creek, which flows north and south through the marsh, and which, it is interesting to observe, forms a natural highway for the Swallows as they go to and from their roosts.

On the sides of this road are several small maple trees, to which the Swallows often resort in such numbers that their foliage trembles as though in a strong breeze, it not being the birds’ object to perch in the trees, but to flutter among the dew-laden leaves, and apparently bathe in the moisture they contain, while between the baths they rest on the smaller terminal twigs, when they are very difficult to observe.^[49] This habit does not appear to have been previously recorded, and I am by no means certain that the explanation offered is the true one.

50. Tree Swallows on wire and nest hunting about pile.

Frequently one or more flocks, varying in size from eight or ten to several hundred birds, may be seen in the road, where I at first supposed they were “dusting,” but soon noticed that most of the birds after alighting in the road were motionless. They did not move about as though searching for food, but occasionally the actions of a pair enabled one apparently to determine the sex of each individual, and more often a bird would pick up a bit of dried grass and fly up into the air with it. Sometimes it was carried fifty yards or more and then dropped; at others, the birds would carry it to the telegraph wires above, and drop it after perching a moment. Without exception, all the birds seen to alight in the road were in the dull, immature plumage of birds of the year, and in their actions, as Mr. William Brewster has remarked (The Auk, 1898, p. 194), they evidently gave a premature exhibition of the procreative and nest-building instincts.^[51]

Additional evidence of the possession of inherited knowledge was apparently given by many Tree Swallows, who were frequently seen hovering about a pile standing in the creek.^[50] At first it was supposed that these birds were feeding on insects which had alighted on the pile; but the number of birds—often a dozen or more—seen fluttering about it, and the persistency with which they remained there, forced the conclusion that in a wholly unreasoning way they were looking for a nesting site.