Art. III. — Notes on the Flesh-eating Propensity of the Kea
[Read before the Otago Institute, 12th June, 1906.]
At a meeting of the Philosophical Institute of Wellington, last session, statements were made to the effect that the mutton-eating habit attributed to the kea (Nestor notabilis) was a myth: at any rate, this was the inference drawn from the reports of the meeting published in the New Zealand Press; and a paragraph founded on this report appeared in Nature for the 28th December, 1905.*
Since this alleged change of habit is of very great interest to biologists, and has received world-wide currency from the account given by Wallace in his “Darwinism” (p. 75), from which it has been copied into many books discussing evolution, it was very startling to be informed that the flesh-eating habit was non-existent in fact, and had only existed in the imagination of certain sheepowners and their shepherds. Biologists have for years been using this alleged change of habit as an illustration of the fact that variation in habit, as well as in structure, occurs in nature; and to be told now that the change of habit is quite mythical is extremely disconcerting.
But what evidence did those who deny the existence of the habit bring forward? And on what evidence is the allegation of the habit founded?
Although I am unable to answer the first question, this is of little consequence, since I am able to give the evidence of some of the many witnesses to the existence of the habit.
As a matter of fact my attention had been called to the subject in conversation with an Australian colleague during the meeting of the A.A.A.S. in Dunedin in 1904; and as a result of that conversation I proceeded to make inquiries of various people in the South Island who were reputed to have had experience of the attacks of the kea on their sheep. And although I made these inquiries to satisfy my own doubts, yet, in view of the importance of ascertaining and establishing the truth (or otherwise) of the matter, I have come to the conclusion to put on record the letters containing the personal
[Footnote] * Immediately on reading this I forwarded a brief note to Nature (12) summarising the facts of the present communication.
experience of a few persons living in Otago at the time the attacks were first noticed.
These letters were in answer to a series of questions which I put to my correspondents, and these answers entirely support the generally accepted opinion that in certain parts of the South Island certain keas have acquired the habit of attacking sheep and of devouring their flesh. These letters, in short, merely confirm the statements contained in Buller's “Birds of New Zealand,” which were founded on the statement of men living in the same localities as some of these same folk to whom I have written. A good account of the matter has already been given by Mr. Huddlestone in 1891 (6).
The history of the matter is, briefly, as follows:—
In or about the year 1867 it was observed that on certain sheep-runs in Otago, in the neighbourhood of Lake Wanaka, sheep were wounded in a rather mysterious manner. It was noticed in the case of sheep killed for food that a healed wound occurred sometimes in the loin or sides; when shearing, too, similar healed and even open wounds were found in or about the region of the loins; also, when mustering, sheep were seen with more or less pronounced wounds, raw and bleeding, and even with entrails hanging out of large holes in the side of the abdomen.
It was on Mr. Henry Campbell's station at Lake Wanaka that the first efforts seem to have been made to trace the origin of these injuries, but similar facts had been noticed on other stations. Mr. Campbell gave instructions to his shepherds to keep a good look-out for the animal that caused the wounds:* so poisoned mutton-fat was laid out in suitable and likely places, and men were set to watch. It was found that keas were attracted and devoured the mutton more or less greedily, and were poisoned thereby; and the suspicion that they were the enemy was soon turned to certainty by the observation of Mr. James MacDonald, at that time (1868) head shepherd, and now a sheep-farmer at Dipton in Southland.† He saw a kea
[Footnote] * It was by some supposed to be a disease. It has even been suggested that the damage attributed to the kea has, in part at least, been caused by gulls (Larus dominicanus). These birds are known to peck at the eyes of lambs, but I am not aware whether they have ever been detected eating sheep or attacking them while alive.
[Footnote] † Mr. John Campbell writes that he believes he was the first to detect the true cause—he states that this was in 1870; but as MacDonald had already reported the occurrence in 1868, there seems either a confusion of dates or Mr. Campbell's memory has played him false as to his being the discoverer, for he states, “The kea was not suspected of attacking sheep in any way in 1868, and not for two years afterwards.” But MacDonald's name is referred to by two or three of my correspondents as being the first to discover the cause of the wounds.
at work on the back of a sheep. I will quote from his letter to me:—
“I do not know whether I was the first to see the kea attack sheep, but I was the first to report it to Mr. Henry Campbell of Wanaka Station.
“In 1868 my orders were to go all over the run after the snowfall and see that the sheep were evenly [distributed] over the ground, that no hill or spur had more sheep on it than it could well carry. While I was at this work, the snow [being] about 2 ft. deep, I went out to the tops: in a small basin under the top, on the west side, facing a rocky country that we called ‘skay,’ there was a mob of sheep snowed in and unable to get out. There I saw the kea at work. He would come down from the rocks, settle on a sheep's loin, and peck into the sheep, which would run through the mob; but [the bird] stuck to the sheep all the time till he got a piece out of the sheep, then he would fly to the rocks. I watched the bird at this work and did not disturb him till I was fully satisfied. … Then I went down to the station and reported to Mr. Campbell. He could not credit me, and all hands on the station [refused to] believe that the birds would do it; so I was ordered to go to another hill, called the Black Hill, and Mr. Campbell came with me, and some more men, and at the first mob we came to Mr. Campbell and the rest saw [the keas] at work with their own eyes.”
The announcement, first published in the Dunstan Times, was received with incredulity and ridicule by Mr. H. Campbell's fellow-sheepowners. But not for long; soon other sufferers noticed the kea at work, and those who had laughed laughed no more.
So serious was the trouble that on Mr. H. Campbell's station men were engaged as “kea-shooters,” one of whom—Mr. John King, of Pembroke—has been good enough to give me a good deal of information, and to send me the names of several of the gentlemen whose letters are printed below; and on their replies to my questions the present communication is founded.
There can be no doubt, it seems to me, that sheepowners have suffered very considerable loss from the attacks of keas; but whether the numbers of sheep killed by them as given by various persons are the correct ones or are exaggerated I have no means of ascertaining. Sir Walter Buller (13) gives instances, so that I need not repeat them. But it will be noticed that Mr. Dougald Bell believes that the kea kills 5 per cent. of the sheep in the region of Lake Hawea, and records the loss of twenty-five during last season. But, seeing that several people attribute their heavy financial losses to the kea, it seems improbable
that the exaggeration would be very great. Surely we may credit these men, directly concerned as they were, with sufficient intelligence to investigate the facts with enough care to convince themselves that the losses were due to keas.
It has been suggested that it was in the interests of shepherds and so forth to exaggerate the loss, so that the bonus on kea-beaks might be kept high. I should imagine that ‘cute men of business, and Scotchmen to boot, would scarcely be so befooled by their men.
The Kea seen at Work.
I have been asked by incredulous folk, “Has any one ever seen a kea at work on the sheep?” I was at one time unable to answer this question, till I investigated the subject, but thanks to my correspondents I am now in a position to say, Most certainly; on plenty of occasions have the birds been seen on the backs of sheep, and shot while at work pecking away at the wool and flesh. (See letters at end of this article.)
Several people—viz., Reischek(5), Fraser, Bell—have examined the crop of the bird and found wool and mutton therein.
I will quote from some of my correspondents' letters in answer to my questions:—
J. Campbell writes, “I was coming down the Matatapu when I saw a mob of sheep rushing about as if a dog was disturbing them. When I got nearer I saw a flock of birds hovering over the sheep. These were keas. I stopped and watched for a few minutes, and presently I saw a sheep singled out from the others and make towards some rocks with a kea planted on its back. By running under rocks and rubbing against them the sheep got the bird off its back; but the same [bird] or another was soon on again. This went on for some time till the sheep became exhausted.”
A. Fraser writes, “I have seen the kea attacking the sheep and also eating into a sheep when the latter was stuck in deep snow. I have opened scores of keas' crops and found wool and meat therein.”
J. H. King says, “I have often seen the birds at work on a sheep, and have shot them while on the sheep's back. I have seen a flock of twenty or thirty birds attack a mob of sheep in high precipitous country. The kea would harass them until one bird would suddenly alight on a sheep's back holding on to the wool of the rump. The sheep so attacked, would separate from the mob and rush frantically about: it would either go over a bluff or drop down from exhaustion.
The kea, which had still held on, was joined by several others, and they soon destroyed [? devoured]* the sheep.”
Again, Mr. Cameron writes, “When 'snow-raking'—that is, taking sheep from high country—keas would gather round the sheep in great numbers, attack one or more quite close to us shepherds. A sheep would get frightened, run out of the flock with one or half a dozen [!] keas on its back, kill or wound it severely before they would let go.”
The majority of my correspondents give a similar account of the facts, and several of them—Messrs. Bell, Cameron, King, McGregor, McKenzie—state that they have often seen keas on the sheep's back; and most of them give details as to occasions on which they have shot the birds while at work.
It must be borne in mind that some of my informants are and always have been managers, and so are less likely to have had the opportunity of witnessing the attacks than the shepherds; and, further, as Mr. Ford states, the attacks are frequently, if not usually, made during the night, and therefore, unless specially watched, their attacks are rarely witnessed. Nevertheless, all the men to whom I wrote have actually seen the bird at work. My correspondents are all, I believe, trustworthy witnesses, and I see no reason to doubt the truth and accuracy of their statements.
Area of Country affected.
The kea is confined to the South Island, and occurs only in the high mountainous parts—i.e., along the Southern Alps and other high ranges. But it is not throughout this country that the kea has been a nuisance to sheepowners. In travelling through Marlborough or in North Canterbury my inquiries met with a negative reply—indeed, some of the men to whom I put the question scoffed at the idea of the bird doing serious damage to sheep. From further inquiries, however, I find that it has been known for some years that along the eastern flanks of the Alps in Mackenzie country, Canterbury down to Earns-law, near Lake Wakatipu in Otago, various sheep-stations have suffered loss from the attacks of the bird. Thus, I have records from Mount Cook Station and Ben Ohau Station, in the first-named district; while the Wanaka, Hawea, and Wakatipu districts yield abundant evidence of the existence of carnivorous keas. And one of my correspondents (Mr. King) gives the Takitimo Mountains as the southern limit. Further, during the present year the farmers of Amuri County, in North
[Footnote] * Throughout this article words or phrases in square brackets are interpretations or paraphrases of mine.
Canterbury, met in conference at Culverden and decided to petition the Government to increase the bonus on kea-beaks.
In the Otago Daily Times for the 16th February, 1906, we read that “the keas have been very numerous in the mountainous parts of Amuri County during the last two years. They have descended on the Amuri highlands from the mountains, and several landowners stated that the losses of sheep attributed to these birds had increased from about 7 ½ to 8 per cent. last year to 15 per cent. this year. Musterers brought reports of having seen sheep killed by keas,” &c., &c.—a repetition of the course of events well known in Otago. While from the same newspaper for the 22nd March, 1906, one learns that on the West Coast, too, the kea is at work: “At Mahitahi, Bruce Bay, in South Westland, Mr. T. Condon lost last year 150 sheep, which he believed to have been killed by keas. He had seen the bird at work on the sheep. … There has been no complaint of the birds attacking the settlers' flocks in the more northern sections of the Coast—as, for instance, round the Franz Josef Glacier.”
But even within the limit of distribution of the kea many stations seem to be free from its attacks. Thus, Buller(13) quotes H. Campbell as stating that, in 1868, when he was suffering from the attacks at Wanaka, the keas were not attacking the sheep at another station owned by him, some thirty miles away, “at the same altitude (4,000 ft. to 5,000 ft.), in the same district, and where the birds are plentiful”; and my own inquiries quite bear out this evidence of the sporadic distribution of the habit.
Is every Kea carnivorous?
I put this question to my correspondents, and the replies render it impossible to give a definite answer: for whereas Messrs. Bell, Cameron, Ford, and Holmes believe that every kea in a district indulges in the habit—as “the old birds teach the younger directly they are fledged,” writes Ford—there are some of my informants who take the opposite view, that “only the more daring bird's” attack sheep (McGregor); that “the habit is peculiar to individual keas in a flock” (McKenzie); and this view is held by Mr. Green of the “Hermitage,” Southern Alps; and I am inclined to share the latter opinion, for if every kea in the district were to become carnivorous the loss to sheep-owners would be much greater than it is.
There are many stations, as I have stated, in the area occupied by the kea whose owners have apparently no fault to find with the bird, and even in those districts where they are most troublesome it is probably only certain birds that are
the victims of this craving for flesh. It is—as some of my correspondents put it—only the more daring and older birds that attack the sheep. Just as, in India, there are only certain tigers that, unprovoked, indulge in human flesh—the “man-eaters”—so, amongst the keas, we must recognise certain “sheep-eaters,” though whether their number is on the increase seems unascertained.
The Kea is still at Work.
It will be seen from the letters that the kea is still at work in, at any rate, certain districts, whereas in some of those stations at which they were formerly a pest the birds at present appear to be less addicted to the habit. This may be owing to the fact that on certain stations it is no longer profitable to keep sheep (see King's letter), or because possibly the “sheep-eaters” have migrated to other regions. At any rate, at Hawea, D. Bell “shot three keas attacking living sheep on the 12th January, 1906—shot one on the sheep's back. I shot eight keas during the term we were mustering in January, and their crops were full of mutton.” And he says that “they kill sheep now as much as ever.” Other evidence from Makarora is to the same effect: “The sheep still come in more or less wounded, and even with the entrails hanging out, and when killed for food, as many as one in four present healed wounds in the back” (Ford). But one thing seems certain, that the birds now go more thoroughly to work, and make a more complete “job” of it than in old days. Then the sheep were usually merely wounded. True, the wounds may have been serious, and some of the sheep died of their wounds. But nowadays the carcase is devoured, the bones are left picked clean. Mr. D. Bell sent me the arm-bones (humerus) of sheep from which the keas had actually extracted the marrow. In each of the four bones sent, a more or less triangular hole had been neatly made by the kea, just below the “head.” (Plate IV.)
Mr. King writes, “One thing has been noticed lately by those who were among the sheep in high country—viz., that the keas when they kill a sheep now pick the carcase clean; leaving nothing but the skeleton, the skin almost turned inside out.”
Mr. Bell also refers to this increase in the damage done to individual sheep. It has been suggested by Taylor White(8) that originally the bird merely sucked the blood, but that it soon discovered that the flesh itself is good to eat, and, as we learn, now recognises the “importance of being thoroughly in earnest” by devouring the entire carcase.
It will be remembered that Wallace states that the bird showed a marked preference for the “kidneys,” and it is very popularly supposed that it makes a special effort to obtain these organs; but, as the majority of my correspondents point out, this is an error. It is a mere accident that the bird, in certain cases, makes its first attack in the region of the kidney, for it is on the rump that the bird finds it most convenient and safest to settle, and naturally pecks at one side or the other of the backbone, working through to the underlying kidney. But, as-a matter of fact, the bird will commence the attack at that part of the sheep which is most prominent: if a sheep be lying on its side in a gully or elsewhere the kea commences at the side of the abdomen.
The eclecticism of the kea is in that exaggerated, as has already been pointed out years ago by Huddlestone and by Taylor White; but such a legend dies very hard indeed.
The Method of Attack.
The method of attack is varied. It may be (a) on the moving sheep; (b) on a fallen sheep; (c) on a snowed-up sheep.
Perhaps the best account of the first method is that contained in Mr. R. McKenzie's letter: “I have seen a kea attack and hang on to a living sheep. The bird flew on to a sheep's back, and commenced driving its beak through the wool into the flesh—not necessarily just over the kidney, as is supposed to be the custom. The frenzied sheep jumped and ran about in any direction for dear life, then, separating itself from the mob, made a direct line down a steep slope, and in its mad career finally dropped over a precipice, until which moment the bird held on with its claws, its wings slightly extended as if to steady itself or to be ready to fly off at any moment. The instant the victim left terra firma the bird relaxed its hold, but was observed to fly almost straight down as if bent on securing the sheep. Both were then lost to view.”
Similar statements occur in other letters (Bell, Cameron, McGregor), and have been made to me by shepherds and others orally.
(b.) A sheep will sometimes, in coming down hill, roll over and perhaps lodge in a gully or elsewhere, and be unable to rise. The kea will then attack. I quote from a letter to the Otago Witness, November 22, 1905, written by Mr. J. A. Wraytt, of Gareton: “When travelling along the bridle-track down the east side of Lake Wanaka I saw a sheep some 50 yards below, kneeling down with its head poked under a shelf of rock. There was a kea on its back, and about half a dozen sitting
on the rocks close by. On going down to the spot I found the sheep, which was or had been a strong, fat one, with most of the wool stripped off its back and lying around in small tufts. There was a large hole through the sheep's loins, into which the kea kept diving and filling its mouth. The others had apparently had their fill, as their heads were drenched with blood.”
(c.) Frequently when the sheep are snowed up, and weakened no doubt by want of food, they will fall victims to the birds. Thus Mr. E. Cameron writes, “A snowslide carried a sheep with it. I happened to be on the hill about the time it happened. It was all covered with snow but its nose and one hind leg, but still alive. The uncovered leg was eaten to the bone—not a scrap left on it—with half a dozen keas fighting over it.”
The kea is known to be a very fearless bird, and we have a record in Mr. King's letter: “One man, who has had a good deal of experience in the high country, tells me that on one occasion, at Lake Ohau, in the Mackenzie country, he saw two keas attack a mob of sheep standing in the yards at the wool-sheds of that station. Shearing was going on at the time, and this was seen by all the shearers present. The birds were shot.”
The sheep do not necessarily die from the attack, for, as mentioned, the animals are frequently observed to present healed wounds when being shorn; and cases are known in which part of the intestine has been actually torn away, and the broken end has adhered to the edges of the hole in the body-wall, so as to form a new exit for the dung. Such a case is recorded in Buller's work, and one of my correspondents—Bell—states that he has met with two instances of it.
The sheep that are selected by the keas as victims are apparently always those in good condition, and with long wool, especially such as have missed a shearing; whereas a newly shorn sheep, or one in poor condition, is never attacked. One readily understands the choice of a well-covered sheep, as it affords a firm foothold for the bird.
Period of the Attacks.
The attacks are most frequent in the spring and winter—when presumably the natural food of the bird is scarce, or covered with snow—but by no means are they confined to these seasons. Further, it may be noted that the night-time is the period during which much of the damage is done, though the bird is not absolutely or entirely nocturnal.
Any one who has spent a few days in the region of the Southern Alps knows that the birds may frequently be seen
during the day; and many people who have spent a night in the Ball Hut on the side of the Tasman Glacier will recall their noisy habits in the early morning, before the dawn.
The Normal Food.
The kea, like other parrots, is normally a vegetarian, though it includes insects in its diet. At any rate, so it appears from the few reliable statements that exist.
According to that accurate observer, the late Mr. Thomas H. Potts(1), the kea gathers “its subsistence from the nectar of hardy flowers, from the drupes and berries of dwarfed shrubs that contend with a rigorous climate and press upwards almost to the snow-line of our alpine giants. To these food-resources may be added insects found in the crevices of rocks, beneath the bark of trees,” &c.
Mr. Potts also states(2) (“Out in the Open,” quoted by Buller in “Birds of New Zealand,” i, p. 168, footnote) that when the snow covers these subalpine shrubs, and insect-life is dormant, the kea is forced to go lower and lower down the mountains to take shelter in gullies, where it feeds on the hard, bitter seeds of the kowhai [Sophora tetraptera], small hard seeds in the fruit of Pittosporum, the black berries of Aristotelia fruticosa (the “native currant”), as well as on the fruit of the pitch-pine and the totara.
The most detailed bill of fare is that given by Huddlestone(6): it includes the grub of such insects as the weta (Deinacrida) and cicada, which are to be found in the ground. “Besides grubs, they fed on the berries of various alpine shrubs and trees, such as the snowberry, Gaultheria, Coprosma, Panax [= Nothopanax], the little black seed in a white skin of Phyllocladus alpinus, the Pittosporum with its hard seed in a glutinous mass like birdlime, and the red berry of the Podocarpus [nivalis], also on roots of various herbaceous plants—Aciphylla squarrosa and A. Colensoi, Ranunculus lyallii, celmisias, &c.”
My own observation, while in the Southern Alps this year, adds to the list the orange berries of the low-growing heath Leucopogon fraseri. Two birds were feeding on these berries within two yards of where I was sitting: they eat the juicy part of the berry, putting out the skin and usually the “seed” also, which I found afterwards on the ground, though now and then I heard the bird crack the seed, so that occasionally, at any rate, it swallows this.
Both Potts and Huddlestone refer to it eating the “hard seeds” of Pittosporum and Podocarpus; but I wonder whether this is habitual; why should they neglect the juicy covering?
Mr. Cameron writes, “The food of the kea is berries, roots of
spear-grass (Aciphylla) and cabbage-tree [Cordyline], and snow-grass [Danthonia sp.]”.
Several of my correspondents note the fact that keas eat “roots,” though they are not in agreement as to what the roots are. Mr. Taylor White (8) suggests—though, on what evidence does not appear—that the bird feeds on “lichens which cover the rocks in high mountainous regions.” This, it seems to me, would be a very innutritious diet, and it is little likely that, in the presence of a fairly abundant choice of juicy berries and other fruits, the bird would touch so poor a food. But it appears from his article that there were no berry-bearing subalpine shrubs in the locality he was acquainted with. Certainly around the “Hermitage,” in the Mount Cook district, the subalpine scrub is abundant, and lichens would, one imagines, be the last resort of the bird.
Mr. McGregor writes, “I have watched a kea picking grubs out of a dead tree, and frequently noticed them picking into the earth for roots, with their beaks.” But none of the above observers, or, so far as I can ascertain, any one else, seems to have examined the crops of any of the birds in an untroubled district—where, that is, the carnivorous habit has not shown itself—so that it is difficult to determine with absolute certainty the whole range of the normal diet of the bird.
The Origin of the Carnivorous Habit.
The above being its normal food, how has it come about that the bird has taken to eating mutton? Various suppositions have been put forward. One of these may at once be disposed of. It has been suggested that the kea mistook a sheep lying down for the plants termed by settlers the “vegetable sheep” (Raoulia mammillaris and R. eximia)! Thus Mr. (now Judge) F. R. Chapman wrote some years ago (7), “It is said that the keas tear them (the plants) up with their powerful beaks, and that these birds learnt to eat mutton through mistaking dead sheep for masses of Raoulia.”
Now, as a matter of fact, these large species of Raoulia do not occur in the Wanaka district, nor on the Southern Alps in the neighbourhood of Mount Cook. None of my correspondents, all of whom know the country round Wanaka well, mention the plant as providing any sort of food for the kea. I think that Mr. Chapman must have been misled. Further, it is extremely doubtful (see later) whether the keas devour “dead” sheep—i.e., such as are found lying on the hills, that may have died of “natural causes”—one, in short, that the birds have not killed themselves.
This “vegetable sheep” business is another myth that ought to be eliminated from the history of the habit.
There can be no doubt that the origin of the habit is traceable to the kea's natural curiosity: its bump of inquisitiveness is very highly developed, and it will investigate any unusual object—turning it over, peeking at it, and so forth.
It is very easy to imagine a kea coming across a fallen still-living sheep or one partially covered by snow, proceeding to pluck at the wool, and so coming down to the skin; then its beak would nibble at the flesh, and the bird would soon find that blood is a good sort of juice to swallow.
Or, as some have suggested (e.g., Mr. McGregor), the bird inquired into the fresh skin of a sheep hanging on a fence, or was attracted by a carcase, newly killed, suspended from a gallows: either of these possibilities seems probable, though only one or two of my correspondents refer to this matter, in reply to my query. It does not seem certain, however, that a kea will feed on a sheep that has died from “natural causes” on the hills. Mr. T. White and several of my correspondents state that they have never seen them thus feeding. At the same time, one of my correspondents refers to the bird devouring the carcase of deer that have been shot and left on the hills; and Buller refers to a dead foal being similarly eaten; and it is also stated that the corpse of a man who fell over a precipice was found torn to pieces by keas. Reischek(5) made the ingenious suggestion that the birds acquired the habit from finding and feeding on maggots which had appeared on the carcase of a sheep which had died on the hills, and “having thus acquired a taste for fat, became emboldened to attack live sheep.”
But these are all suppositions, and if it be true that the bird does not in fact touch a dead sheep, these suppositions cannot be true.
Whether the habit is related in any way, originally, to a scarcity of food does not seem at all clear; the answers are all rather vague, and there is a diversity of opinion on the matter. Thus Mr. King writes, “I do not think that scarceness of the natural food had much to do with the attacks. I have been told that the kea attacks sheep in the West Coast in the low country close to the bush, where food would be plentiful.” But that this scarcity has occurred is certain. The burning-off of the alpine scrub and the bush in gullies, as has occurred in many districts, would deprive the bird of its normal food during the whole year; while elsewhere, when the normal food is covered by snow in winter-time, the bird would be compelled to seek a new diet, or migrate, or die. The kea has met the problem by adopting the first of these three alternatives; and as, at the same time as
the burning occurred, the sheep were introduced into the district, a new source of food was at once open to it. And the suggestion that the kea, on the disappearance, temporary or permanent, of its normal food, would proceed to investigate a fallen sheep, or one snowbound—weakened perhaps from cold or absence of food—seems quite in accordance with the bird's general habit of inquiry and its catholicity of diet.
The change of diet is not so abrupt as at first appears, since part of the bird's food consists of flesh in the form of insects, and possibly there is not a great amount of difference in taste between a good, fat, juicy weta or beetle grub and a piece of raw sheep, while the case with which a whole flock of birds can obtain a full meal must be a distinct improvement upon the more wearisome task of digging in the earth and probing rotten logs for a small mouthful as a reward.
The observations of birds kept in captivity are few, and not entirely in agreement. Dr. DeLautour (as quoted by Buller from the Field) noted that his bird—which was the first living specimen to be exhibited in the Zoological Gardens in London—ate only the flesh and would not touch the fat, preferred mutton to beef, and was not averse to pork. Reischek states that a kea he had in captivity preferred meat to vegetables.
I had a caged kea under observation for a week, through the kindness of Mr. Harry Buckland of Waikouaiti. We fed it normally on various vegetables, such as carrots and parsnips, and on fruits, such as apples and bananas, all of which it seemed to like. We tried it with mutton flesh and fat, and so long as we watched it the bird neglected the meat, though it ate it during the night. On two occasions we presented it with a saucer containing cut-up vegetables, mutton—lean, fat, and kidney. It went to work at once on the vegetables. On one occasion it did not eat the mutton so long as daylight lasted, but during the evening we found that it had devoured the flesh, later on the fat, and next morning the pieces of kidney had disappeared. On the second occasion—on which it had not been fed during the earlier part of the day—it again attacked the vegetables first, later the flesh, then the fat, and lastly, during the night, the kidney. Of course, this bird may not have developed a carnivorous habit before its capture, some three months previously, for, as I have pointed out, only some keas exhibit the taste for mutton. Moreover, it must not be supposed, I think, that even a bird that has once developed the habit eschews vegetable diet thereafter; it is likely that its diet will be a “mixed” one.
Nor is the kea alone in evincing a liking for flesh; its near ally the kaka (Nestor meridionalis), normally a honey and
grub eater, has been observed to devour mutton. Travers (3) states that “They are fond of raw flesh, and I have seen them hovering in front of a sheep's pluck hung on a tree… eating fragments which they tear off, giving preference to the lungs.”
At the time that Wallace referred to this new food-habit of the kea it was the only case of the sort known. But a closely analogous instance has been described for an African starling, the “rhinoceros-bird” (Buphaga), which formerly fed upon ticks and insects infesting the skin of herbivora. But a few years' ago the cattle-plague decimated the herds of wild and domestic cattle, antelopes, &c., and it is now found that the bird, thus deprived of its natural food, has become carnivorous. It pecks holes in the skin of healthy beasts, and even eats their ears off, causing wounds from which the animals frequently die—at any rate, causing considerable damage (9).
Correspondence and Inquiries.
I wrote letters containing a series of questions to some fifteen persons, whose names had been given to me by various people as likely to have first-hand acquaintance with the bird and its depredations. These fifteen persons are, or have been, actively engaged in connection with sheep-runs in the neighbourhood of Lakes Wanaka, Hawea, and Wakatipu, and elsewhere. I have received replies from ten, which replies are embodied in the present article.
To these ten gentlemen I am extremely obliged for the courtesy and readiness with which they gave me every information I asked for:—
Dougald Bell, now owner of Hawea Lake Station, has had thirty-three years experience of sheep-farming in the district round Lakes Wakatipu, Hawea, and Wanaka. His first observation was in the Hunter Valley (Hawea) in 1874; his last, in 1906, at Lake Hawea.
Ewan Cameron, of Pembroke, was shepherding on the Crown Range in 1868; and has had experience of kea-attacks on the Matukituki, and Matatapu, and right branch of the Shotover.
John Campbell, now of Cromwell, at one time shepherd at Wanaka West.
William Ford, at one time shepherd on Mr. H. Campbell's station, has ever since been sheep-farming in the Wanaka district.
Alexander Fraser, now Stock Inspector in Nelson, was at one time sheep-farming in the Wanaka and Hawea districts (1871-83), and suffered severe losses of sheep from kea-attacks.
M. Stuart Holmes, now of Kakanui, has been sheep-farming since 1874, and was at one time manager of Lake Wanaka Station (1881-82).
John King, of Pembroke, was at one time engaged as “kea-shooter” on H. Campbell's station in the “seventies,” and has had a long experience in that district.
James MacDonald, now a farmer at Dipton, Southland, at one time head shepherd on Henry Campbell's station at Wanaka.
Robert McGregor, of Hawea Flat, speaks of the attacks at Triplet Peaks, Lake Hawea, from 1877 to 1883.
Roderick McKenzie, now of Birchwood, Southland, was part owner in 1889 to 1891 of Hawea Lake Station.
In addition to these correspondents, have received information of kea-attacks from Mr. James W. R. Green, now porter at the Hermitage Inn, Southern Alps. He had been employed as rabbiter at Mount Cook Station, and has shot keas while attacking sheep. And from some other sources I have obtained information.
In addition to answering a series of questions which I sent them, several of the above gentlemen wrote letters containing their personal experiences, which appear to be of Sufficient interest to entitle them to be placed on record.
1. Mr. Dougald Bell.
“Hawea Lake Station, 20th February, 1906.
“In reply to yours of the 20th November re keas killing sheep … I can safely say that they kill 5 per cent. of the flocks in all the country that is infested with keas. As a matter of fact, this season in my small flock [number not given] during the time we were mustering I personally counted twenty-five sheep killed by keas; I also shot three keas killing a live sheep. I shot one of them on the sheep's back, tearing away at the kidney-fat and meat. [The majority of my correspondents do not lay stress on this, and no doubt Mr. Bell merely means that the bird was tearing away at this region.] After I shot the keas, the sheep, a big, strong, half-bred wether, which was holed all along the back and ribs, managed to get up and walk away, but he would be sure to die, as he was too much holed and worried to live. I shot eight keas during the time we were mustering in January last, and they were all full of mutton in their stomachs [crops].
“There is another matter I should like to point out to you about keas: when they have eaten all the flesh off the bone, then they tackle the shoulder [i.e., humerus] and leg bones, and take all the marrow out of the bone by chipping the bones
with their beaks until they obtain an entrance. I am sending you four shoulder-bones, some old, and some fresh ones killed last winter. [One of these is here figured.]
“There is also another point: Two sheep came in during mustering at Hawea Lake—a ewe and a wether—which had been attacked by keas some time during the season. Each had holes in their backs, and the main gut had been cut through and pulled up through the backs; the gut had grown to the [skin of the] back and [a new anus had been formed] which caused a black streak down each flank where the droppings fell out. One of these cases happened in the year 1887 and the other in 1899. It was in the month of January that they mustered in each case, and brought into the station for shearing when [the above facts were] noticed.
“I have had thirty-three years' of experience with keas, and so know a little about them. I first came up here in 1873. When the keas first started to attack sheep they used to pull a tuft of wool off the back of the sheep over the kidneys for a while before killing [I presume he means that they merely tasted the flesh and left the sheep], but now it is very different, as nearly every sheep they tackle they kill outright.
“There is a lot of country in this locality that could be stocked with sheep if it were not for the keas: but it is not safe to put sheep on it, as the birds would kill half of them.”
2. Mr. Ewan Cameron.
“Pembroke, 28th September, 1905.
“The first notice of keas killing sheep in Wanaka was in 1868 by James McDonald, head shepherd for Mr. Henry Campbell, owner of Wanaka Station at that time … Mr. Campbell wrote a letter to the Dunstan Times describing the destruction that keas were causing among his sheep, with the result that all the people in that part of the country laughed at him.
“In that year I was shepherding in the Crown Range, and after reading Mr. Campbell's letter I saw at once what was killing my sheep. The place of attack is nearly always on the loin, behind the last rib; they [keas] tear down to the kidney, pull out the entrails, and sometimes leave the sheep without killing it. It is a common thing for sheep to come into the yards with their entrails hanging over the side; also with new wounds, or old ones healed up.
“[As an instance of the ferocity of the keas, I may mention that] One season, at the head of the Matukituki, I had four hundred sheep that did not come in at the proper time for shearing. I put them in a safe place after snowfall at the beginning
of winter: when I went to shift them on the 1st September [I found that] the keas had killed two hundred of them: a good many were devoured, and some not touched but with the usual wound above the kidneys.
“Rose Bros. had a run on the Matatapu, a continuation of the same range I was on. They mustered their sheep (about three thousand) in the beginning of winter, left them in a large mountain paddock at night, and next morning found thirty-five killed.
“They [the keas] do most of the damage at night. On another occasion, on my own run, a snowslide carried a sheep with it. I happened to be on the hill about the time it happened, and saw the sheep still alive but covered with snow except its nose and one hind leg: the uncovered leg was eaten to the bone, not a scrap [of flesh] left on it, and half a dozen keas fighting over it.”
3. Mr. John Campbell.
“Cromwell, 13th August, 1906.
“I have much pleasure in telling you what I know of this wonderful bird. I first saw the kea in the Wanaka Lake district in '68…. I was shepherding at this time on what was then called ‘Campbell Station’ (Wanaka West), and often killed numbers of keas when out on the mountains towards nightfall…. As regards their attacks on sheep, I think I was the first to see the kea on a sheep's back. The shearers often drew our attention to a scar on the sheep's hack opposite the kidneys, and being on the same place on each sheep, some thought it was a disease (for some were found dead wounded in the same way). The kea was not at all suspected until some time afterwards.
“I was coming down the Matatapu (boundary between Wanaka and Wanaka West Stations)* when I saw a mob of sheep rushing about as if a dog was disturbing them. When I got nearer I saw a nook of birds hovering over the sheep. These were keas. I stopped and watched for a few minutes, and presently I saw a sheep get singled out from the others and make towards some rocks with a kea planted on its back. By running under rocks and rubbing against them the sheep got the bird off its back, but the same one or a fresh one was soon on again. This went on for some time till the sheep was exhausted. I
[Footnote] * In a second letter he writes, “It was late in the year '70 when myself and mate, David Kinnard, were coming home from Glencoe to Glendhu on Wanaka Station. We saw sheep on the hill-top disturbed as by dogs. I went to the top, but Dave would not come up.”
then went down and drove away the birds and examined the sheep, which had the wool and flesh torn by the birds in the same spot as that previously noticed by the shearers. This solved the mystery, and when I related the story to the station-manager and fellow-workers they were greatly surprised to learn that the kea was the culprit….
“I am convinced that the chief reason why the bird attacks the sheep in that particular spot is because it is the only place that it can perch for any length of time without the sheep putting it off.” [He does not believe in the keas seeking after the kidney-fat.]
4. Mr. Alexander Fraser.
“Nelson, 2nd August, 1905.
“In reply to yours of the 22nd ultimo, I was engaged sheep-farming in the Hawea and Wanaka Lake district between 1871 and 1883. Suspicion arose in the first-named period that keas were attacking sheep, suggestion being that they learnt it from picking at sheep-skins and carcases hung on gallows. I lost some thousands of sheep from keas. I have seen the kea attacking the sheep, and also eating into a sheep when the latter was stuck in deep snow. I have opened scores of keas' crops and found wool and meat therein. I have laid poison in dead sheep in snow, gone back later and found dead keas; also have often-poisoned keas with mutton suet [poisoned, I presume]. The natural food originally of the kea was berries, and grubs and insects it dug out of the ground. The burning of the alpine country probably diminished its natural food. They breed inside broken rock. Never found a nest. Keas are very numerous between the above dates, though shot and poisoned by the thousand.”
5. Mr. John King.
“Pembroke, 22nd July, 1905.
[Part of this letter has already been quoted above, and many of the facts contained in it are incorporated in the general account. It continues:] “I have seen sheep snowed up on the ranges, and on one occasion I counted twelve dead out of about fifty, and numbers of keas sitting about on the rocks gorged, very much after the manner of vultures. On another occasion I was with Mr. Campbell and some of his shepherds who had a large mob of sheep in front of them taking them across some hilly country, when we noticed two keas hovering over the sheep. Presently one swooped down on a sheep not 30 yards from where we were. This sheep immediately left the others and rushed past me. I was carrying a gun at the time, and shot the bird
on the sheep's back. I could recount many instances where I have seen the keas at work, but probably what I have written may suffice.”
6. Mr. R. McKenzie.
“Birchwood, Southland, 23rd October, 1905.
[I have quoted portion of Mr. McKenzie's letter on page 78, describing one method of attack, as being a very clear account.]
“The habit of attacking sheep I firmly believe to be peculiar to individuals in a flock. I also believe the reputed slaughter by keas of hundreds or even scores of sheep in a single night to be gross exaggerations. On one occasion, during a snowstorm, when two or three hundred sheep had been hemmed in for a few days, I found three or four sheep killed and mostly eaten up by the birds. …
“With regard to the bird digging in over the kidney, I believe this to be accidental rather than by design or instinct, for as the maddened sheep tries to escape by running away—always down-hill—the bird hangs on to the highest part (that is then the rump just over the kidney) of the sheep, and begins operations there.”
Potts, 1871: Nature, iv, 489.
Potts, “Out in the Open.”
Travers, 1872: Trans. N.Z. Inst., iv, 210.
Menzies, 1878: Trans. N.Z. Inst., xi, 376.
Reischek, 1885: Trans. N.Z. Inst., xviii, 98.
Huddlestone, 1891: N.Z. Journ. Sci. (n.s.), 198.
Chapman, 1891: N.Z. Journ. Sci. (n.s.), 203.
Taylor White, 1895: Trans. N.Z. Inst., xxvii, 273.
Lankester, Nature, lxii, 366.
Otago Daily Times, March 22, 1906.
Otago Daily Times, Feb. 16, 1906.
Benham, 1906: Nature, lxxiii, 559.
Buller, “History of New Zealand Birds,” i.
Explanation of Plate IV.
Outline of humerus of sheep which has been opened by a kea.—a, a. The surface of this bone has been picked away, exposing the canceller structure. b. The cavity of the shaft exposed by the removal of a somewhat triangular piece of bone.
All the four humeri had been opened by the kea at this spot, in order, no doubt, to get at the marrow.