As if to heighten the dramatic interest of our studies (I come now to the promised mystery), we had already had the singular good fortune to find a male humming-bird who seemed to be stationed permanently in a tall ash-tree, standing by itself in a recent clearing, at a distance of a mile or more from our widow's orchard. Day after day, for at least a fortnight (from the 2d to the 15th of July), he remained there. One or both of us went almost daily to call upon him, and, as far as we could make out, he seldom absented himself from his post for five minutes together! What was he doing? At first, in spite of his sex, it was hard not to believe that his nest was in the tree; and to satisfy himself, my companion "shinned" it, schoolboy fashion,—a frightful piece of work, which put me out of breath even to look at it,—while I surveyed the branches from all sides through an opera-glass. All was without avail. Nothing was to be seen, and it was as good as certain, the branches being well separated, and easily overlooked, that there was nothing there.
Four days later I set out alone, to try my luck with the riddle. As I entered the clearing, the hummer was seen at his post, and my suspicions fastened upon a small wild apple-tree, perhaps twenty rods distant. I went to examine it, and presently the bird followed me. He perched in its top, but seemed not to be jealous of my proximity, and soon returned to his customary position; but when I came back to the apple-tree, after a visit to a clump of oaks at the top of the hill, he again came over. I could find no sign of a nest, however, nor did the female show herself, as she pretty confidently might have been expected to do had her nest been near by. After this I went to the edge of the wood, where I could keep an eye upon both trees without being myself conspicuous. The sentinel spent most of his time in the ash, visiting the apple-tree but once, and then for a few minutes only. I stayed an hour and a half, and came away no wiser than before. The nest, if nest there was, must be elsewhere, I believed. But where? And what was the object of the male's watch?
My curiosity was fully roused. I had never seen or heard of such conduct on the part of any bird, and the next forenoon I spent another hour and a half in the clearing. The hummer was at his post, as he always was. We had never to wait for him. Soon after my arrival he flew to the apple-tree, the action seeming to have no connection with my presence. Presently he went back to the ash, and drove out of it two intruding birds. A moment later two humming-birds were there, and in another moment they flew away in a direction opposite to the apple-tree. Here, then, was a real clue. The birds were probably our sentinel and his mate. I made after them with all speed, pausing under such scattered trees as had been left standing in that quarter. Nothing was to be found, and on my return there sat the male, provokingly, at the top of the apple-tree, whence he soon returned to the ash. A warbler entered the tree, and after a while ventured upon the branch where the hummer was sitting. Instead of driving her away he took wing himself, and paid another visit to the apple-tree,—a visit of perhaps five minutes,—at the end of which he went back to the ash. Then two [kingbirds] happened to alight in the apple-tree. At once the hummer came dashing over and ordered them off, and in his excitement dropped for a moment into the leafy top of a birch sapling,—a most unnatural proceeding,—after which he resumed his station in the ash. What could I make of all this? Apparently he claimed the ownership of both trees, and yet his nest was in neither! He sat motionless for five minutes at a time upon certain dead twigs of the ash, precisely as our female was accustomed to sit in her apple-tree. For at least seven days he had been thus occupied. Where was his mate? On the edge of the wood, perhaps. But, if so, why did I hear nothing from her, as I passed up and down? Again my hour and a half had been spent to no purpose.
Not yet discouraged, I returned the next morning. For the three quarters of an hour that I remained, the hummer was not once out of the ash-tree for five minutes. I am not sure that he left it for five minutes altogether. As usual, he perched almost without exception on one or other of two dead limbs, while a similar branch, on the opposite side of the trunk, he was never seen to touch. A [Maryland yellow-throat] alighted on one of his two branches and began to sing, but had repeated his strain only three or four times before the hummer, who had been absent for the moment, darted upon him and put him to flight. A little afterward, a red-eyed vireo alighted on his other favorite perch, and he showed no resentment. The day before, a warbler had sat on the same branch which the yellow-throat now invaded, and the hummer not only did not offer to molest him, but flew away himself. These inconsistencies made it hard to draw any inference from his behavior. During my whole stay he did not once go to the apple-tree, although, for want of anything better to do, I again scrutinized its branches. This time I was discouraged, and gave over the search. His secret, whatever it might be, was "too dear for my possessing." But my fellow-observer kept up his visits, as I have said, and the hummer remained faithful to his task as late as July 15th, at least.
Some readers may be prompted to ask, as one of my correspondents asked at the time, whether the mysterious sentry may not have been the mate of our home bird. I see no ground for such a suspicion. The two places were at least a mile apart, as I have already mentioned, and woods and hills, to say nothing of the village, lay between. If he was our bird's mate, his choice of a picket station was indeed an enigma. He might almost as well have been on Mount Washington. Nor can I believe that he had any connection with a nest found two months afterward in a pitch-pine grove within a quarter of a mile, more or less, of his clearing. It was undoubtedly a nest of that season, and might have been his for aught I know, so far as the mere fact of distance was concerned; but here again an intervening wood must have cut off all visual communication. If his mate and nest were not within view from his ash-tree perch, what could be the meaning of his conduct? Without some specific constraining motive, no bird in his normal condition was likely to stay in one tree hour after hour, day after day, and week after week, so that one could never come in sight of it without seeing him. But even if his nest was in the immediate neighborhood, the closeness and persistency of his lookout are still, to my mind, an absolute mystery. Our female bird, whether she had eggs or offspring, made nothing of absenting herself by the half hour; but this male hardly gave himself time to eat his necessary food; indeed, I often wondered how he kept himself alive. Is such a course of action habitual with male hummers? If so, had our seemingly widowed or deserted mother a husband, who somewhere, unseen by us, was standing sentry after the same heroic, self-denying fashion? These and all similar questions I must leave to more fortunate observers, or postpone to a future summer. Meantime, my judgment as to the male ruby-throat's character remains in suspense. It is not plain to me whether we are to call him the worst or the best of husbands.
FOOTNOTES:
[13] These two humming-bird papers were printed in consecutive numbers of The Atlantic Monthly, June and July, 1891.