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A HISTORY OF CERTAIN GREAT HORNED OWLS.1

[With 8 plates.]

By CHARLES R. KEYES.

My experiences with great horned owls (Bubo virginianus, especially with a pair under my observation for several years, have often suggested a contrast and comparison with Mr. Finley's work on the California condor. In several respects our subjects and experiences show a certain broad resemblance. Both birds belong to the family of birds of prey, the one being the largest of the North American vultures, the other the greatest of all the owls. The condor has passed into legend and literature as the largest bird of flight and the most graceful when on the wing; the great horned owl occupies a place no less important in legend and literature as the symbol of brooding wisdom and solemn mystery. In both our studies, too, the rare privilege was enjoyed of extending our observations over the whole home period of the bird's life, from the eggs in the nest to the young ready for their first excursion into the outside world.

In most respects, however, our stories are as much in contrast as they could well be. The condors had their home in one of the wildest and most inaccessible of Californian mountain regions; from their nest rim the owls could look out upon five farmhouses, with their numerous outbuildings, and one schoolhouse, all within a radius of 500 yards, and all neighbors of other homesteads and schoolhouses set down in the very peaceful and nonmountainous State of Iowa. The condors, in their wild environment, were tame and well-disposed from the first and grew constantly more docile as the study of their home life proceeded, proving to be, apparently, the gentlest of all the raptorial birds; the great horned owls, with surroundings that would seem to teach peace, had bad dispositions to begin with, and these constantly grew worse, until, after six weeks of suspense and with the longest of our claw marks still unhealed, my assistant and I felt a sense of relief when the young owls finally took to the tree tops, leaving us with fairly whole physiognomies and the feeling that we

1 Reprinted by permission from The Condor, a magazine of western ornithology, Hollywood, Cal., vol. 13, Nɔ. 1, January-February, 1911, pp. 5-19.

had done the best we could, under the circumstances, to preserve the record of an unusual set of conditions. The great horned owls had proved to be, without much doubt, the fiercest of all the birds of prey. In one further respect, unfortunately, our experiences were in contrast to those of Mr. Finley and Mr. Bohlman. We found it impossible, by any means at our command, to secure satisfactory negatives of the adult birds.1 We were unable to take them at distances of less than 30 feet, and in every case they so blended with their background of gray bark, or gray bark and patches of snow, as not to be worth while. We regretted our inability to try the effect of a blind to operate from, but the mechanical difficulties in the way of such an attempt demanded more time for their solution than we had to give. We therefore gave our attention to the nest and contents, or rather as much attention as the old birds would allow us to give. As the adults were necessarily much under observation, it is hoped that a record of their conduct may add some interest to the present article. The beautiful deciduous forest, stretching for miles along the north bluffs of the Cedar River to the west of Mount Vernon, had by 1890 been reduced to various detached groves of from 10 to 100 or more acres each in extent. About February of this latter year I was hunting through one of the larger of these groves, which, if one struck straight across the fields, was only a mile and a half from town. I remember watching the short, uneasy flights of a great horned owl, but without locating his mate. I also remember talking with Mr. McFarland, a sturdy Scotchman who has occupied his homestead just across the road from the owls' hunting grounds since the early fifties, and learning that "big hoot owls have always been in that timber." Soon after the great oaks and hard maples of the eastern two-thirds of the grove fell under the ax, leaving to the west only a 25-acre remnant and, in the cut-over area, only some old white elms and a few young maples and lindens. Among these latter the forest soil soon gave way to a thick carpet of blue grass, and so what had been heavy forest was gradually transformed into a rather open and still very beautiful timber pasture. It was taken for granted that the owls had moved elsewhere, and for a series of years what had been famous Sugar Grove was practically forgotten. From 1901 on, however, my way several times led across the pasture and into the timber tract, and I was surprised to note there each time the presence of great horned owls. Once or twice I even took some pains to find a possible nesting site. There appeared to be none, so I concluded that the owls were merely transients. On February 6, 1906, just at nightfall a friend and I were walking along the public highway which

1 The portrait of the adult owl shown herewith (pl. 2,) was taken several years ago from a fine specimen brought in to the Cornell College biological laboratory. The picture was made by a student of zoology, who left the negative as property of the college.

forms the north boundary of the pasture and the woods. Suddenly the hooting of big owls boomed out from a near-by linden of the timber pasture, and there, sure enough, were both birds engaged in ardent courtship and not minding our presence in the least. They stood facing each other on the same branch and, with feathers ruffled and heads bobbing, were hooting in low tones as they side-stepped toward one another and greeted one another with low bows. Finally they flew away, side by side, into the timber tract. That these were transient birds was beyond belief; so, on February 17, after allowing what seemed to be a fair margin of time, I decided to give the vicinity a thorough search. To make the story short, the nest was at last found in the very place where previously it had not seemed worth while to look. It was not in the heavy timber at all, but in one of the large elms of the pasture, and, moreover, hardly more than 50 yards removed from the above-mentioned public road where teams were constantly passing. Toward the south the view was wild, open, and picturesque enough; to the west, north, and east, at distances varying from 200 to 500 yards, were the schoolhouse and farmhouses, as above stated.

A more fortunate set of conditions for the study of the owls' home life could hardly be hoped for. The short distance from town has already been indicated. The nest was in a large shallow hollow, 28 by 32 inches in diameter at the bottom, with an entrance 18 by 20 inches in diameter set at an angle of 45° and facing toward the southeast. The hollow was only 8 inches deep on the exposed side, thus permitting fairly good illumination. Of still more importance the nest site was only 22 feet from the ground and a strategic branch some 5 feet above the nest afforded a point of attachment for a ladder combination from which pictures might be taken. As great horned owls generally make use of old hawks' nests placed in the tops of the largest trees the good fortune of this modest elevation can readily be appreciated. At the very moment when this nest was discovered a second pair of these birds was domiciled in a redtail's nest placed in a tall white elm in heavy timber 3 miles to the northwest and just 92 feet above the ground. Further, the proximity of farmhouses made certain the necessary supply of ladders and ropes. Mr. Benedict, who lived just across the road and only 200 yards to the east, and Mr. McFarland, whose house stood only 75 yards farther to the east, were our interested and generous benefactors. Our opportunities were indeed great and, as I said, we greatly regretted our inability to make better use of them.

The weather on February 17 was fairly moderate, with the snow melting slightly, though the preceding days from February 6 had been stormy enough, with temperatures as severe as 10 below zero. But the sitting bird was wonderfully protected from the storm

winds of the north and west and flushed from three large perfect eggs that lay in a slight hollow of the decayed wood on the north side of the cavity. It seemed to me out of the question, with such temperatures as February and March were sure to bring, to obtain any pictures without having the owls put their date a little later in the season; so, after a little quick thought, I pocketed these eggs and went home. My conviction that the owls would not abandon so ideal a site after a probable occupancy of years was fully confirmed when, on March 23, three more eggs were found, just like the first and lying in exactly the same little hollow.

Saturday, April 7, was the first warm day of spring. On this day. Mr. W. W. White, a student in Cornell College, and I made the first attempts to secure pictures of the owls' home and surroundings. Mr. White's ingenuity proved greater than my own and to him are to be credited the scheme for getting a camera within range of the nest and the successful picture of the eggs in situ. He also took the front view of the nest tree, looking northwest and showing the general situation and the interesting structure of the big elm itself. I merely helped him with the necessary ladders and ropes. Our two 20-foot ladders, lashed together and drawn up with a guy rope so as to rest on the aforesaid strategic branch, made anything but a solid foundation from which to work. Nevertheless all the near views of the nest were taken from this unsteady perch, the camera being tied with strings to the sides and rungs of the topmost ladder.

On April 14 two young were found in the nest and the remaining egg was much pipped. Both young were entirely blind and only one gave much sign of life. This was done by uttering a querulous little note somewhat like that of a very young chicken when excited but not sufficiently frightened to peep. The older one was able to hold its head up slightly while the smaller was entirely helpless. Both shivered as if from cold, the day being cool and showery. In the nest cavity were a headless bobwhite and the hind parts of an adult cottontail rabbit. The weather conditions prevented our trying to secure a negative. On April 19 only two young were found in the nest, with nothing at all to indicate the fate of the third egg. The young appeared quite lifeless, allowing their bills, which were of a slaty color with darker tips, to rest in the decayed wood of the nest bottom. The feather sheaths were pushing out on the dorsal and scapular tracts, and at the tips of these the brown juvenile plumage was beginning to show. The primary quills were also sprouting but the feathers themselves were still entirely concealed. The nest cavity contained a headless adult rabbit and a headless coot, also the hind parts of a young rabbit about the size of a striped gopher. No assistant was available on this day. On April 21 the young showed very noticeable increase in size, the brown feathers now showing

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