Economic Control Of Rabbit Urged

Press, Volume CII, Issue 30094, 30 March 1963, Page 7

Economic Control Of Rabbit Urged

Eradication of the rabbit in New Zealand is impracticable, according to an American, Dr. W. E. Howard, who is associate vertebrate ecologist at the agricultural field station at the University of California at Davis. Dr. Howard has been visiting Canterbury this week. Nor does he believe it is desirable. His view is that in many areas the rabbit never has and never will constitute a problem. He advocates economic control, using improved techniques where the rabbit does constitute a problem, and he holds that improved farming practices such as oversowing and topdressing create conditions of cover that may as effectively control the pest as shooting and poisoning.

In 1957 Dr. Howard studied the rabbit problem in New Zealand as a Fulbright scholar. Now on sabbatical leave he is nearing the end of a year’s stay to aseist the Department at Scientific and Industrial Research and the Forest Service in planning for improved control of animals that are noxious to certain protection forests. “To attempt to eradicate rabbits simultaneously from all of New Zealand appears to be both impracticable and too costly,’’ he says. “I think that the time has arrived when rabbit boards should start learning how little rabbit control is required, especially in areas where rabbits have never been a problem. Why not let the new objective be ‘economic control’ —one of trying to reduce costs rather than rabbits to he irreducible minimum. “To determine what degree if control, K any, is needed in an area is really not a hazardous experiment ‘because, should rabbits start to become a problem, they can easily be brought under con’rol again. The Rabbit Destruction Council and rabbit boards are experts on how to (control rabbits, so no serious risk is involved. “The objective of economic control is to reduce the density of a pest animal to the level where the animal’s damage becomes tolerable. Economic control is interrelated with damage. The primary damage that rabbits now do in New Zealand is to compete with sheep and other livestock for forage, although they can be a nuisance in other ways too. Obviously a few rabbits are not an economic problem in pastures. In many places rabbit populations are static and will not increase much even if left alone. “The success of any rabbit control operation is measured by the degree and permanency with which rabbit damage has been reduced in that area. Killing rabbits where there is no damage, especially where there fj ncs , even potential damage, is not economic oanteol.” s' ■* Dr. Howard suggests that since the rabbit cannot’'be eradicated it is pefihaps time that more people learned to enjoy the occasional rabbit. There was no need to be afraid of rabbits. They would never again become the problem they once were because farming practices had changed the'habitat. "We must also remember that economic losses and nuisance factors are often compensated to varying degrees by aesthetic, sporting and other beneficial values." he said. , ‘.‘Rabbit hunting is good sport and rabbits also taste good. Rabbits have played an important role in the New Zealand way of life in training youth how to hunt Boys are much less likely to shoot native pigeons and blackbirds when there are rabbits for them to stalk “Bare ground, year-round short-grass conditions, burn-

ing of tussock, wide and gravelly river bottoms, and almost any situation which provides a considerable amount of bare ground or short herbaceous. vegetation favours the rabbits. “Man’s former practice of indiscriminate summer burning of tussock grasslands to make them palatable to sheep is whait enabled rabbits to occupy the tusssck grasslands of Central Otago and the Mackenzie Country. “Without meaning to lessen the credit due to those who are in charge of rabbit control. for they have accomplished a tremendous feat, it should be pointed out that the potential number of rabbits that have been controlled biologically through the establishment of New Zealand’s famous pasture grasses and the programme of topdressing probably exceeds that which has been achieved by shooting and poisoning in many parts of New Zealand “Seeding, topdressing, rotational grazing, and partial spelling do not favour rabbits. The resources of many rabbit boards might be better used to clear gorse and otherwise make the habitat unsuitable to rabbits rather than ‘chase the occasional rabbits.’ This comment also applies to opossums. ’’

Dr. Howard says that initially the cost of all pest control operations is usually high, but before too long the cost of any control programme should be placed on an economic basis where the expenses are reasonably proportionate to the damage being done. After noting that in 1961-62 rabbit control in New Zealand cost about £1.4 million he asks how these costs could be reduced The most important way to save money would be to change the eradication policy to one with economic control as the objective, he says “One also wonders if there are not ’too many chiefs and not enough Indians’. With 185 rabbit boards there must be more than 1500 board members who meet regularly to discuss and supervise about 1000 rabbit control employees. Liaison between boards is poor, although the Rabbit Destruction Council’s newsletter is helping to overcome this deficiency.

“Perhaps the existing rabbit board method is the best for New Zealand, but I would think that several welltrained Government men, perhaps from the Department of Agriculture, should be the ernes to have the authority to advise rabbiters and local control boards (rabbit boards* on the best techniques, and these experts should be the ones to hold the purse strings, as far as making recommendations for subsidies and grants, and to help settle disputes as to who should be rated for rabbit control: I see no reason for making farmers pay rates if they do not have an economic rabbit problem and their rabbits are not a serious problem to neighbours.

"My suggestion is that either many of the rabbit boards should amalgamate into regional control organisations to reduce the amount of ‘brass’ trying to direct a lesser number of rabbiters, or they dissolve themselves and turn the responsibility over to existing territorial governments, but with each local group of rabbiters being supervised to some degree by a few well-trained Department of Agriculture officials.” Dr. Howard said that far more organised research needed to be done on methods of controlling rabbits for there always would be rabbit slow work but would save problems. It was expensive considerable money in the long run.