This morning a female Downy Woodpecker that I was watching flew to a horizontal branch and proceeded vigorously to bathe in the loose snow lying there. Like a Robin in a puddle, Mrs. Downy ducked her head, ruffled her feathers, and fluttered her wings, throwing some of the snow over her back and scattering the rest to the winds. As all the snow fell off one part of the branch, she moved along to another, until she had cleared a place about two feet long. Two forks held more snow than the straight limb, and apparently Mrs. Downy enjoyed herself immensely when she came to them.
Dr. Arthur A. Allen (1928) in his admirable “Downy Woodpecker’s Story,” published in the School Department of Bird-Lore, says, letting the bird tell its own story: “When cold weather sets in, * * * I begin drilling roosting-holes where I can spend the nights. I usually have to drill quite a number for they seem to be quite popular with other birds like the Chickadees and Nuthatches, and sometimes when I get ready to retire I find my hole occupied by a flying squirrel or a whole family of deer mice, and it is easier to drill a new hole than to drive them out. One winter I got tired of drilling holes and every night retired to a bird-house and perched on an old Wren’s nest that was in it.”
Many ornithologists, even as long ago as the time of Wilson and Nuttall, have believed that the rows of small holes, such as we commonly see in the bark of our orchard trees, are drilled by the downy woodpecker. These little holes, about three-eighths of an inch across, circular when old, but oval when fresh, are arranged in fairly regular rows parallel to the ground, and sometimes in tiers, when they have the appearance of a waffle. In settled regions they are found oftenest in the trunks and the larger branches of trees belonging to the rose family—most commonly of all in apple trees. The holes may be within 3 feet of the ground or as high as 20 feet or more above it, depending on the height of the tree. Oftentimes they are very close together; I have counted as many as six of them in the space of an inch and a half. The question has arisen whether the downy woodpecker ever makes these holes.
We know now, what the older ornithologists did not know, that it is a regular habit of the yellow-bellied sapsucker to drill such holes, but there are plenty of statements in the ornithological literature today ascribing the work to the downy woodpecker as well.
Dr. Charles W. Townsend (1932) gives an able summary of the literature on this question and, after carefully weighing the evidence, comes “to the conclusion that these well known and characteristic circles of holes are made by true sapsuckers and not by downy or hairy woodpeckers.”
He throws a good deal of doubt on some seemingly definite observations from correspondents quoted by Forbush in his “Birds of Massachusetts,” when he says that “many leave one in considerable uncertainty as to whether the correspondents actually saw the downy woodpecker making the rings of holes, or merely tapping in the same region, or drinking the sap, or eating cambium from holes whose origin was not ascertained. It may be that some of the correspondents were unable to distinguish the true species of woodpecker.”
Dr. Townsend cites several observations, two of which are quoted below. If the first of these had not been correctly interpreted, and if the other had not been seen in its entirety, they might have led to error. He says:
There is one observation, however, which should be quoted here, as it is of considerable interest in this discussion, an observation made by a capable observer with great care. Forbush says, loc. cit., vol. II, p. 268: “The first trustworthy evidence, however, that I obtained regarding the tapping of trees for sap by the Downy Woodpecker was in 1899, when my assistant, the late Charles E. Bailey, on April 6 watched one for several hours. His report reads: ‘At 12:30 I found a Downy Woodpecker, and watched him till 2:45; he took three larvae from a maple stub, just under the bark. He next tapped two small swamp maples, four and six feet from the ground, and spent most of the time taking sap. He tapped the tree by picking it a few times very lightly; it looked like a slight cut, slanting a little. The bird would sit and peck the sap out of the lower part of the cut. The cut was so small the sap did not collect very fast. The bird would go and sit for a long time in a large tree and not move, then it would come back and take more sap. It did this three times while I was watching it. It did not care to take any food but the sap.’ * * * Mr. Bailey cut off and brought me the limb, the bark of which was perforated by the bird. * * * The perforations passed through the bark to the wood, but did not enter it and they do not in the least resemble in shape those made by the Yellow-bellied Sapsucker.” Here is just what we should expect in a woodpecker not specialized as a sapsucker. * * *
The next record is of considerable significance in this discussion, and had I seen only the latter half of the drama, my conclusions might have been different. In the Wenham swamp on May 11, 1906, my notes state that Glover M. Allen and I found a Yellow-bellied Sapsucker drilling holes in a white pine. His movements were slow and he paid little attention to us standing below him at the foot of the tree. When he departed, a female Downy Woodpecker visited the holes.
Speaking of his own observations, Dr. Townsend says: “I may state that, although I have long watched Downy Woodpeckers gleaning insects on and in the bark and wood of trees at all seasons of the year, I have never seen them dig circles of holes in the bark. * * * I have never found fresh rings of holes except during the time of the sapsucker migrations.”