Art. XXIV.—On Rabbits, Weasels, and Sparrows.
[Read before the Hawke's Bay Philosophical Institute, 13th October, 1890.]
I am sorry to see from newspaper report that the members of the Hawke's Bay Rabbit Board have decided against the importation of weasels. As this subject is sure to be considered again, sooner or later, it may be worth while to say a few words in favour of the weasel and its introduction to our lands. So far as I understand, the objection brought forward may be called a fear that “the balance of nature” should be upset—i.e., What are the weasels to do when the rabbits are killed? Very well, so far. But let me put several questions which may throw light on the matter. How far back in the
history of Britain can we trace both the rabbit and the weasel Was either beast introduced by man to that same island, or may we suppose both rabbit and weasel lived side by side in Britain when men were few and far between, and dressed themselves in skins, or coloured their naked bodies with woad —at which time the most of Britain would be covered with dense forests and swamps? Under such conditions, could man be a valuable agent to check the undue increase of either animal race? The rabbit, as an article of food, would be taken by man. But for what reason should primitive man check the undue increase of the weasel? If the weasel was left unchecked to increase at will, why did it not exterminate the rabbit, then the game-birds, then the sheep, then cattle and horses, till at last man had finally to succumb before this energetic little blood-sucker? Seeing that rabbits were hunted by man, how was it the rabbit did not speedily become extinct, having man, dog, wolf, fox, weasel, and others constantly killing it? What is there remarkable about New Zealand, as compared with the Britain of the past, which gives the idea that weasels would in this country be endowed with extra vitality? Does not man aid in keeping “the balance of power” among the animal kingdom? Where rabbits are scarce may he not destroy weasels and protect the rabbit, and vice versa, and so play one against the other?
I come from a district famed in English history, the old forest of Sherwood, and have stood under the shadow of Robin Hood's oak, an aged giant among trees, under which Robin and his men in green, the bold foresters of “Merrie Sherwood,” held their tryst. Now, why did not the law speedily check these freebooters, who slew, with bow and arrow, the king's deer, and feasted thereon, not forgetting the tax they levied on the purse of the wealthy traveller? They were able to hide successfully in the trackless forest and escape the king's soldiers. There were formerly many local ballads recounting the various exploits and encounters of Robin Hood and his merry men, which were very popular. Most of these would seem to be now lost. Sir Walter Scott introduces some of these erstwhile heroes in “Ivanhoe:” Robin Hood, under the disguise of Locksley, the archer, as also the “sturdy clerk of Copmanhurst,” otherwise known as Friar Tuck, who has a bout at fisticuffs with King Richard himself. For even some in holy orders were fain to join in this free and jovial life. “The Miller of the Dee” was another celebrated character; also “Maid Marian,” Robin's wife, and “Little John,” his lieutenant, who, notwithstanding his nickname, was considerably over 6ft. in height. Robin is sometimes thought to have been the exiled Earl of
Huntingdon. I give part of a modern song, in vogue some thirty years ago:—
The monks of old famed stories told
Of knights of chivalrous arms,
When the guerdon of the warrior bold
Was the maiden's peerless charms,
When bold Robin Hood and his foresters good
Were merry as merry could be,
When the forester's life was free from strife,
And his home was the trysting tree.
Then, hurrah, hurrah, for bold Robin Hood;
Hurrah for the olden times,
And one cheer more for each forester good,
Who lives in the olden rhymes.
This wilderness of forest was harbour for rabbits and weasels equal to any of our New Zealand wilds. Cultivation and population, both, have largely increased in historic times, and we must not consider the Britain of the past as similar to the Britain of the present.
Some people point to the wonderful increase of the house-sparrow in its new home, and say, “Look at that; who'd ha' thought it!” Now, I can show they might have known what the result would be by looking back on this bird's history, provided they could do so as I can myself. Nearly fifty years ago, when New Zealand was a very small place, and I myself also small, I can well remember that public payments were made in England to induce the boys to destroy the house-sparrow. When a very little fellow I used to make a practice of catching these birds, and saving their heads, which had a market value. When a good necklace of heads was collected I would go to the workshop of the village carpenter, who also must have collected rates or taxes, or in some way had the authority to disburse certain moneys. His name I remember well—Chadwick; he would count the heads, and then give me a few of the large pennies current in those days. So you see, some fifty years ago, at Cuckney, in Nottinghamshire, England, it had been found necessary to devise means to check the undue increase of the house-sparrow, and it is every way possible that the same verdict had been passed against the sparrow a hundred years previous to the date mentioned. The hedge-sparrow is of quite a different character, and must not be classed with the other. I think it has been found impossible to bring so delicate a bird the long voyage to New Zealand. This matter of head-money for the destruction of the sparrow, if disputed, can most likely easily be proved by referring to the rate-books of that date in the district mentioned, or probably in most other parts of England.
Here is a cutting from the Otago Witness, of the 3rd July, page 7, which accurately describes one of the traps used fifty years ago, and also advocates the importance of waging continual war with the sparrow of to-day in England, as was the case many years ago: “Speaking of the sparrow nuisance, a correspondent of the Field says, ‘In consequence of a note in your columns I have lately tried one of Wyatt's (of Bristol) sparrow-traps, which in shape is like a large spittoon made of wickerwork, and find it most successful. It is placed where the poultry are fed, and six to eight sparrows are caught daily. I generally leave one hen-sparrow in the trap as a decoy. When one considers that a single pair of sparrows will rear from eight to ten young ones during the next three months, these traps seem to deserve a trial wherever sparrows are numerous.’ “The writer omits to mention a small door in the side of the trap to collect the captured birds from, which find entrance under the centre of the downward sloping top, and seldom or never think of returning by the same way. This little extract shows that the war with the sparrow has been kept up all these years, and that they still hold their own in spite of everything.
Now an argument is founded by persons ignorant of the above fact. They say, “See how the sparrows have increased in New Zealand. If we are foolish enough to introduce weasels they are sure to do the same.” I know of no proof, historical or otherwise, that weasels ever increased unduly in England; and, if it were not for the special eagerness with which game is preserved in certain places, the weasels would mostly be left unmolested, as they are in other districts where game is not the particular object. In New Zealand “the balance of nature” is at present upset by the undue increase of the rabbit, so man requires to place the weasel in the opposite scale and hold the balance in his hand.
Since writing the above, I have received my copy of vol. xxii. of the Transactions, and have read Mr. Coleman Phillips's paper on rabbit-disease. Although advocating the spreading of fluke through the agency of dogs, he allows the necessity of using natural enemies as aids in destruction also. A letter from Mr. W. Brodie, President of the Toronto Natural History Society, is included in the same paper, which shows that the wolf, fox, lynx, fisher (Mustela pennantii), marten (M. americana), and horned owl (Bubo virginiana) are in that district the rabbit - destroyers. All these are dangerous animals to introduce into New Zealand. The three first are sure to destroy sheep and lambs. The fisher and marten are tree - climbers. As Mr. Brodie remarks, “They are good tree-climbers, thus easily eluding the pursuit of dogs.” It is a well-understood fact that it is of vital importance
to the agriculturist that the number of insectivorous birds should be increased rather than diminished. So these tree-climbing Mustelidæ are not admissible, for they take not only the nests of eggs, but the birds also when at roost in the trees. I notice Sir James Hector, in his letter to the Minister of Mines,* remarks that he is of opinion they would in New Zealand leave the open country and take to the forest. This is decided evidence against them. Sir James continues, “the British martens have even a worse reputation than the polecat as destroyers of lambs.” I take exception to this. First, I am of opinion that there are no British martens, properly so-called, for martens are tree-climbers; and I maintain that the killing of lambs, and even assaults by companies of weasels on man him self, are old fables and not properly authenticated. Of the polecat I have no certain knowledge, other than that it is almost or entirely extinct in Britain.
The horned owl is a deadly enemy to all game-birds, and extends its depredations even within the Polar regions, where it plays havoc with the ptarmigan, a species of grouse. From this it is evident that the less we have to do with importations of such Canadian animals the safer it will be.
Mr. A. R. Wallace, in “Darwinism,” says, “the sable (Mustela zibellina), unlike other animals and birds, when resident within the polar circle, is not in the habit of assuming the white coat, but retains its rich brown fur throughout the Siberian winter, for owing to its tree-climbing proclivities it finds a harbour from pursuit among the trees, with the bark of which its colour assimilates, and not only feeds partially on fruits and seeds, but is able to catch birds among the fir-trees.” This is a remarkable habit, and causes the sable to feed occasionably on the same food and copy some of the actions of the squirrel, which is of the family Rodentia and a congener of the rabbit.
Why the marsupial native cats of Australia (Dasyuridæ) are not spoken of as a check on the rabbits in that country is curious, for they are decidedly carnivorous, and I have known one take a full-grown laughing-jackass (Dacelo gigantea) which was crippled in the wing, and was so kept within the palingfence of a garden. This occurred at night; and the cries of the bird, when being dragged under the house, during the small hours, were weird and startling.
To all who will take the evidence of persons living in rabbit-infested districts in New Zealand and Australia it is clearly proved that trapping, poisoning, or hunting are a continual drain on time and money, without any permanent
[Footnote] * Trans. N.Z. Inst., vol. xxii., p. 320.
result, for the whole series have to be constantly gone over again and again. So the already depleted profits from the land are further lessened by costs of fines and expenses incurred, by maintenance of a large staff of men and dogs, purchase of poisoned grain, fencing, &c. If the weasel is not speedily imported to Hawke's Bay, a large proportion of our settlers, who are now barely making a living, will have to throw up their holdings.
The Mount Nicholas Station, Otago, consisting of 75,000 acres of mountain-pasture, when in my occupation, easily carried twenty thousand well-fed sheep. Within some four years after the first rabbit was killed the then owners were practically ruined by rabbits. I saw in the newspapers some two years ago that the run only carried two thousand sheep, and the occupier, Mr. Nichols, was so harassed by fines inflicted on account of rabbits that he petitioned to be relieved from the lease of the land, which was not granted, and in despair, I believe, he cleared out to some other country.
In regard to spreading bladder-fluke by the aid of dogs, to me it seems just as probable that ultimately sheep might be affected, though perhaps not by that special disease itself, but one kindred to it as it were, in a different guise, for these low forms of organism appear to change their character according to what host they occupy; though how scientists can with certainty trace them in their various phases and transmigrations as they alternately occupy animals, snails, earthworms, other animals, and so on, I am at a loss to understand. Surely it can be only guesswork at the best. Years ago a relative, a medical man in large practice, wrote to me: “I do not know the disease—scab—you speak of in your sheep, but you should be careful of your dogs, for the tapeworm from the dog will cause fluke amongst sheep.”
The fluke in Australia, though perhaps not the form he alluded to, is generally the result of wet pastures. Formerly we in New Zealand bought imported merino ewes from Australia. I had some at Mount Nicholas, which had lived on those dry hills some four years after leaving Sydney. Some of these, when fat, were occasionally killed for mutton. Speaking one day to a shearer who had knowledge of the fluke, he, to my surprise, said, “I will show you some.” As luck would have it, one of these Sydney ewes was being killed at the time. The man cut open a main gall-duct on the liver, pressed his finger along the duct, when, floating in the juice of the gall, came veritable flukes of different sizes, the largest fully three-fourths of an inch long, and resembling greatly in shape an ordinary flounder or flatfish. Here was evidence of the parasitic cause of the disease continuing to inhabit its host apparently for years, and propagate its kind without
leaving; but, the surroundings not being favourable, the increase of the parasite was on so small a scale that the sheep themselves were perfectly healthy; and some of this importation of sheep must have lived to the age of twelve years or more. This surely is good proof that the fluke-parasite procreated its kind without ever leaving its host, which is contrary to what science teaches; for, if it or its eggs had once left its host, the dry nature of the pasture would have proved unfavourable to further development, and they would have lost their vitality. Such an incident as this should be of great interest, and its correctness may be fully relied on. I never tried or saw this experiment performed on sheep bred in New Zealand.
My conclusions are that the weasel and stoat should be the only enemies introduced, unless the black-footed ferret of the prairies, mentioned by Sir James Hector,* is devoid of the knowledge of tree-climbing, which presumably it would be, as those regions are mostly almost without timber. It is possible this may be the small hardy, dark-coloured ferret I used in England when a boy, which I was told was a cross between the ferret and polecat, and which was obtainable in England some forty years ago.
[Since this paper was written I have turned up the following in a book, “The Oxonian in Norway,” written by the Rev. Frederick Metcalf, M.A., second edition, published 1857, page 87. After remarking on ·3 being paid in Norway for each pair of the claws of the golden eagle, he says, “Surely this is a more sensible arrangement than that of those numskull churchwardens of —–, who pay for sparrows' heads out of the church-rates, although a pair of them, while feeding their young, destroy, according to Buffon, four thousand caterpillars weekly.” Mr. Metcalf and Buffon side with the sparrow; but I certainly agree with the churchwardens. There are plenty of real insectivorous birds; so there is no need to rely on the doubtful aid of the sparrow.]
[Footnote] * Trans. N.Z. Inst., vol. xxii., p. 321.