# The Peregrine Falcon at the Eyrie/General Remarks On the Peregrine

Chapter VI.
General Remarks On the Peregrine.
The most striking and entirely unexpected fact noticed was that after the first few days the Falcon turned over to the Tiercel the duties usually assigned to her sex—spending her time abroad hunting and bringing the quarry to the Tiercel, who remained at home to feed and look after the young. This hitherto unrecorded trait in their domestic life should, as I said before, commend the bird to Suffragettes in search of a totem. Moreover, the Falcon, whether actuated by hatred of man or not, showed me her version of the hunger strike, a fearsome thing as watched by mere man with one eye on his own future, for in the avian version it is the husband and helpless young that do the starving. What makes me believe that what I saw is the natural habit of the Peregrine is that in this crisis the Tiercel, though evidently anxious to feed the young, never attempted to do any hunting himself, although there were plenty of birds about. It would have been interesting to have seen whether in the end hunger would have driven him to hunt, and having appeased it he would then have fed the young. But the spell of instinct remained unbroken, for at the last the Falcon arrived with a bird. That the Peregrine does not always kill in mid-air is shown by rats, barnyard chicken and nestling shags appearing on the bill of fare. That the Tiercel did leave the island at times was shown by the fact that, like the Falcon, he at some time of each day betrayed by his bedraggled plumage that he had been having a bath.
Having no exaggerated veneration for the printed word which I too often find is copied from one text-book to another in default of original observations, I always try, like a model jury, to purge my mind of preconceived ideas, and in the case of the Peregrines my only working hypothesis was that the Falcon is bigger than the ​Tiercel; if that is wrong, then all my observations of the inverted vole of the sexes in their care of the young goes by the board. Owing to constant association I soon found myself able to tell which bird was present, though, as in the shepherd's ability to distinguish different members of his flock, it would not be easy to at once reduce the process to writing. The Tiercel of this pair had a much larger cere than the Falcon, i.e., the yellow bare skin round the eye showing, as I have learned since, that he was the older of the pair. The cere, owing to foreshortening, disappears when the bird is seen full-face, and in the same way the pose and condition of the plumage, as well as changing expression, help to make identification difficult, but there is also a massiveness about the Falcon which helps to distinguish her from the Tiercel.
As regards the prey, there seemed no selection as to kind; it looked as if with the Falcon the only rule were first come, first served. In the same way I failed to trace any design in the condition of the quarry as delivered. As far as I could make out, if she kept the Tiercel waiting, and presumably turned up with a freshly killed bird, it was intact, whereas the longer she had it in her keeping, the more thoroughly was it plucked and skinned; but this is purely surmise, as from my circumscribed outlook I got no proof of the Falcon waiting to be called. The natural way of feeding the young is for the adult to divide the prey among the young. If it were usu4l for the prey to be simply dropped into the eyrie, as happened when on occasions the Falcon brought a bird during the Tiercel's absence, I think the young males would have stood a very poor chance beside their voracious sisters—that is, presuming I am right in concluding that the larger young are females. My friend, the late Colonel Moore, when I pointed out the difference in size among the 1910 brood, said that in the Raptores generally incubation starts with the first egg laid, and that the young vary in size accordingly. From what I had seen of two young ravens in the previous year, I dissented. I do not know what the books say about it, but I have since satisfied myself that as regards Peregrines this is a sexual difference, although I have not gone to the length of dissecting them. As I said at the beginning of the book, from the early appearance of this difference in size I ​thought it quite possible that it might be discovered in the egg. Confirmation of this view reaches me while revising these sheets, in a letter from King, who says he visited the eyrie on April 9th, 1913, and found three eggs, one of which was larger than the others and weighed fifty-eight grains more, the difference between the two small eggs being not more than a grain. Notwithstanding their liveliness in getting to the front when feeding was going on, and the fact that the Tiercel always seemed to take care that the males got enough, yet one always seemed to fare the worst, so that at the end of their stay in the eyrie, though there was no perceptible difference between the two females, one of the males might always be singled out as the Benjamin of the family.
In 1911, owing to there only being two, the increased allowance of food led, as in the case of ravens, to their more rapid development. It was on an occasion when the Falcon dropped a hen blackbird into the eyrie, and after watching for a minute or two flew away, that I got the only evidence I have seen of the sense of taste. The young female, after eating steadily for some minutes, at last got to the intestines. Then I saw her pass a loop through her beak, snapping her mandibles as if tasting it and then, dropping it, she shook her head and retired behind a rock. There must have been something wrong about this blackbird, for the young male, who immediately dragged it into a corner, after eating for ten minutes, came to the front and was violently sick three or four times, bringing up a little red casting each time. I got no evidence of the sense of smell, and although Dr. Penrose has lately given an example of its use in the stone curlew, I have never been able to satisfy myself of birds becoming aware of my presence by its means. The most striking example was when, in a hiding tent by a marshy mud flat, with the wind behind me, black-headed gulls, a peewit and a curlew walked past without becoming aware of my presence. Quite different was the behaviour of two sheep that strayed that way; each, as it got my scent, sniffed, threw up its head and hurried away. I have blown tobacco smoke at a golden ​plover sitting seven feet away without disturbing him, and at the Tiercel five feet away, and although, he looked quizzically at it he never minded the smell, which was convenient in my case. Their sense of hearing is extremely acute, although, as in other birds, constant repetition of a sound which is not followed by anything untoward leads eventually to no attention being shown. This trait, owing to superior boldness, was more marked in the Tiercel than the Falcon, and this sexual characteristic was also evident in the full-fledged young. I have not had any opportunity of watching the, young being trained to hunt after they leave the eyrie, but can readily believe that it is more efficient than when undertaken by the falconer. Sight is extremely acute, and on one occasion, when the Tiercel was standing on C, staring full-face at the lens which I was slowly moving, I suddenly realised that I was face to face with stereoscopic vision. I know this is altogether heterodox, and I know that belief is not proof, and although I failed to see how to prove it, I have little doubt that he was fixing both eyes on my proceedings. The third eyelid, which flashes across the eye now and again from the inner corner, is filmy and easily overlooked. It is represented in the human eye by the little fleshy lump in the inner corner. As, regards their psychology, I look upon birds in general as absent-minded beggars, with rather more reasoning powers than we, their rich relations, credit them with. By absent-mindedness I, of course, mean their wonderful instincts. Of the Peregrine language I only learned three phrases; but the use of a hiding contrivance greatly enlarges one's appreciation of bird-language, a rich field awaiting investigation by ornithologists.
The Tiercel Off Duty.
Light 3, Plate speed 250, Subject number 100, Stop F16, Exposure 1-25sec.