THE RABBIT PEST.

New Zealand Journal of Agriculture, Volume XV, Issue 4, 20 October 1917, Page 206

THE RABBIT PEST.

H. MUNRO,

Inspector of Stock, Wellington.

The necessity for' utilizing the food resources of the Dominion to their fullest capacity for war purposes has recently been put forward on several occasions in support of the contention that rabbits,- being a valuable article of human food, should not be wantonly destroyed by methods which render their carcases unfit for human consumption. This, like many other economic theories which appear sound to those who are not conversant with both sides of the question, may gain sufficient support to do considerable harm if well advocated and permitted to pass without contradiction. ,

After twenty years’ practical experience in dealing with the rabbit question in all its branches in different parts of the Dominion the writer is firmly convinced that every acre of rabbit-infested area represents a loss in revenue according to' the extent to which it is infested, and, further, that instead of being valuable food rabbit is so inferior in this respect as to be unworthy' of comparison with the other edible meats produced in this country.

THE ECONOMIC SIDE.

Dealing with the economic side of the question, it is generally acknowledged that five rabbits will consume and destroy sufficient grass to maintain one ewe in profitable condition. Allowing that the average age at which rabbits are killed for marketing is one year, at the present market rates the five rabbits would give an annual return of 55., as against the 255. which could be produced from the average ewe which they are replacing. This comparison applies only to the infested areas which are within reach of the market, but when the greater extent of affected areas which are not w thin reach of

the market is also taken, into account the case for the rabbit is made infinitely worse, for here they give no return whatever for their keep, and not even a lame economic excuse can be put forward to justify their continued existence. It must be remembered, moreover, that as a rule the landholder receives none of the return (if any) from the rabbits he feeds. While it is impossible to arrive at' any approximate estimate of the number of rabbits in the country at any time, we have only to consider that their number at all times runs into millions in order to realize roughly the extent of the loss for which they are responsible.

DAMAGE TO PASTURE-, AND DISEASE.

The value ■of the grass rabbits consume without giving anything approaching an adequate return does not by any means ' complete .the case against them. In some districts they, have done serious and in many cases practically irreparable damage to large areas of pasture. They are connoisseurs in the selection of locality and vegetation, congregating in the warmest localities in infested areas, where they eat out and in many cases totally destroy the most succulent vegetation, leaving the colder land and the coarser pasture to stock. ’ In some localities where they were once numerous, but, where their number has since been reduced to a minimum, some of the pasture has taken from ten to twenty years to recover from the effect of their ravages, and much of it will probably never fully recover its former productivity. Their excrement and urine are particularly obnoxious to other animals, and stock thrive badly on pasture which is fouled by them, even when the quantity and quality of the grasses appear otherwise sufficient and 1 satisfactory. Where they have been numerous over an extended period the pasture retains their taint for a long time after they have ceased to pollute it.

Rabbits are so susceptible to internal parasitic affections that in some districts the mortality among them due to this form of disease has been found sufficient in itself to keep their numbers low for considerable periods. The writer has had experience in localities where approximately 50 per cent, of the mature rabbits were found to be affected with hydatid cysts.

RABBIT AS AN ARTICLE OF FOOD.

The poor and mangy condition of the majority of the several thousand dogs which were formerly kept in . Canterbury and Otago for destroying rabbits, and which were exclusively fed on the latter, supplied an excellent gauge of the value of rabbit as an article of food. The condition in which these dogs were usually seen was not due to natural unthriftiness or want of proper care, but principally to the inferior food-value of rabbit, and in a lesser degree to the

prevalence among them of tapeworm due to eating rabbits affected with hydatids, of which the dog is the natural host.

For several years the writer fed dogs for certain times exclusively on rabbit, and at other times exclusively on mutton of such poor quality that it would not be used for human consumption, and always found the latter infinitely superior to the former for the purpose. Very few animals will eat rabbit from choice, and it is a common saying that natural enemies of the rabbit, such as weasels, ferrets, cats, &c., will not touch fur if they can get —meaning that they will not prey on rabbits if they can secure birds. While their choice in the matter is regrettable their judgment must be regarded as sound.

The value of rabbit as a food for animals can safely be taken as a good indication of its value as human food. So far as ,the writer is aware there are very few of our people who will eat plain, unadulterated boiled or roast rabbit from choice, although there are many who like a nicely cooked. and seasoned rabbit at intervals as a change of diet.

THE TRAPPING . INDUSTRY.

' The rabbit trapping and export industry can only flourish in districts where rabbits are so numerous as to constitute a menace to the agricultural and pastoral industries, and it is not in the interests of those connected with the industry that rabbits should be exterminated or their numbers reduced below a certain limit on any country from which they are able to draw supplies. It therefore follows that the existence of such an industry in any district instead of being an assistance is an obstacle to the .extermination or proper control of the . pest. The man-power which is employed in the industry represents some of the best unskilled labour in the Dominion, and it could be much more profitably employed in some' other way. In order to be a successful trapper a man requires to have energy and initiative, and as men possessing these qualities can earn good money at trapping, that industry , secures their services. The wages of the trappers depend solely on the number of rabbits they are able to catch, consequently they will continue to work on a block of country only so long, as they are able to earn a good wage, and when no longer able to do this they will move to a fresh block where the rabbits have again ’ become numerous as the result of a few months’ rest. The number of rabbits left on country where a trapper is no longer able to earn good wages is always ample to enable such prolific breeders to again become numerous in the course of a few months if other means of destruction are not adopted in the interval. The business of men trapping rabbits for the industry is to kill, so far as possible, only what is suitable for the market, and the destruction of the young rabbits, which are not suitable for that purpose, is directly opposed to their interests.

The activities of the natural enemies of the rabbit, such as weasels, ferrets, cats, and hawks, which are of inestimable value in rabbitinfested country, are also opposed to the interests of the trapping industry, and trappers do not and cannot be expected to take an interest in their preservation. . •

CONCLUSION

In conclusion, no proper place can be claimed for rabbits in the economic life of this country, and any person who discovers a more efficient method of exterminating them than those now in use will deserve well of his country by ridding it of a pest and at the same time providing a ready means of greatly increased production.